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The openMosix HOWTO

Live free() or die()

Kris Buytaert


and Others

Revision History                                                             
Revision v1.0.3                        18 june 2004                          
Minor Fixes                                                                  
Revision v1.0.2                        29 july 2003                          
RPM Build                                                                    
Revision v1.0.1                        19 july 2003                          
Major updates                                                                
Revision v1.0                          09 july 2003                          
Minor updates                                                                
Revision v1.0                          11 may 2003                           
At last                                                                      
Revision v1.0 RC 1                     07 may 2003                           
Major Cleaning                                                               
Revision v0.95                         04 april 2003                         
Replaced ClumpOS by PlumpOS                                                  
Revision v0.94                         25 february 2003                      
Patches by Mirko Caserta                                                     
Revision v0.93                         16 february 2003                      
Extra features and fixes                                                     
Revision v0.92                         21 january 2003                       
Revision v0.91                         27 september 2002                     
Revision v0.90                         03 september 2002                     
Revision v0.71                         26 August 2002                        
Spleling Fexis                                                               
Revision v0.70                         22 August 2002                        
Stripped out empty parts, replaced Mosixview with openMosixView              
Revision v0.50                         6 July 2002                           
First openMosix HOWTO                                                        
Revision v0.20                         5 July 2002                           
Latest Mosix HOWTO (for now)                                                 
Revision v0.17                         28 June 2002                          
Revision v0.15                         13 March 2002                         
Revision v0.13                         18 Feb 2002                           
Revision ALPHA 0.03                    09 October 2001                       

"The best way to become acquainted with a subject is to write a book about
it." (Benjamin Disraeli)

Table of Contents
I. Introduction
    1. Introduction
    2. So what is openMosix Anyway ?
II. Installing openMosix
    3. Requirements and Planning
    4. Distribution specific installations
    5. Autodiscovery
    6. PlumpOS
    7. Cluster Installation
III. Administrating openMosix
    8. Administrating openMosix
    9. Tuning Mosix
    10. openMosixview
    11. Other openMosix related Programs
    12. Common Problems
    13. Hints and Tips
    14. (stress)Testing your openMosix installation
IV. Running Applications on openMosix
    15. Improving Compiling Performance
    16. Imaging with openMosix
    17. BioInformatics and openMosix
V. openMosix Development
    18. Getting started with openMosix internals
    19. the openMosix FAQ
    20. PlumpOS FAQ
A. How to produce openMosix's Kernel RPM files
    A.1. How to produce openMosix's Kernel RPM files
B. More Info
    B.1. irc
    B.2. Further Reading
    B.3. Translations
    B.4. Links
    B.5. Mailing List
C. Credits
D. GNU Free Documentation License
    How to use this License for your documents

List of Tables
2-1. Pros of openMosix
2-2. Cons of openMosix
4-1. Other Directories
8-1. Changing /proc/hpc parameters
8-2. /proc/hpc/admin/
8-3. Writing a 1 to the following files /proc/hpc/decay/
8-4. Informations about the other nodes
8-5. Additional Informations about local processes
8-6. more detailed
8-7. extra options for mosrun
10-1. how to start

I. Introduction

Table of Contents
1. Introduction
    1.1. openMosix HOWTO
    1.2. Introduction
    1.3. Disclaimer
    1.4. Distribution policy
    1.5. New versions of this document
    1.6. Feedback
2. So what is openMosix Anyway ?
    2.1. A very, very brief introduction to clustering
    2.2. The story so far
    2.3. openMosix in action: An example
    2.4. Components
    2.5. openMosix Test Drive
    2.6. Pros of openMosix
    2.7. Cons of openMosix

Chapter 1. Introduction

1.1. openMosix HOWTO

In the beginning there was Mosix, then came openMosix, in my opinion a more
interesting project. Not only from a technical point of view but also due to
the more correct license. I made the decision to focus this HOWTO on
openMosix rather than on Mosix, mainly based on the fact that openMosix has a
bigger userbase. (Moshe Bar states that about 97% of the old Mosix community
has switched over to openMosix.) (20020705) Given the above, lots of
information might be valuable to both users of Mosix and openMosix. I decided
to split the HOWTO. The latest release of the Mosix HOWTO, containing info
about both Mosix and OpenMosix will be 0.20 My intention is to focus on the
openMosix HOWTO, however not neglecting the Mosix users. More info on http://

1.2. Introduction

  This document gives a brief description of openMosix, a software package
that turns a network of GNU/Linux computers into a computer cluster. Along
the way, some background to parallel processing is given, as well as a brief
introduction to programs that make special use of openMosix's capabilities.
The HOWTO expands on the documentation as it provides more background
information and discusses the quirks of various distributions.

Since the creation of this HOWTO some people of the Mosix team created
openMosix (more info later), initially both openMosix and Mosix were
discussed in this HOWTO. Although lots of information might be valuable to
both users of Mosix and openMosix. I decided to split the HOWTO. The latest
relase of the Mosix HOWTO, containing info about both Mosix and OpenMosix
will be 0.20 and can be found on

Kris Buytaert got involved in this piece of work when Scot Stevenson was
looking for somebody to take over the Job: this was during February 2002.
While initially we discussed both Mosix and openMosix, this version of the
HOWTO now mainly focuses on openMosix. Please note that the document often
still mentions Mosix where it should read openMosix.

  You will notice that some of the headings are not as serious as they should
be. Scot had planned to write the HOWTO in a slightly lighter style, as the
world (and even the part of the world with a burping penguin as a mascot) is
full of technical literature that is deadly. Therefore some parts still have
these comments. 


1.3. Disclaimer

 Use the information in this document at your own risk. I disavow potential
liability for the contents of this document. Use of these concepts, examples,
and/or other content of this document is entirely at your own risk. 

 All copyrights are owned by their respective owners, unless specified
otherwise. Use of a term in this document should not be regarded affecting
the validity of any trademark or service mark. openMosix is Copyright (c) by
Moshe Bar. Mosix is Copyright (c) by Amnon Barak. Linux is a Registered
Trademark of Linus Torvalds. openMosix is licensed under version 2 of the GNU
General Public License as published by the Free Software Foundation. 

 Naming of particular products or brands should not be seen as endorsements. 

 You are strongly recommended to take a backup of your system before major
installation and backups at regular intervals.  

1.4. Distribution policy

 Copyright (c) 2002 by Kris Buytaert and Scot W. Stevenson. This document may
be distributed under the terms of the GNU Free Documentation License, Version
1.1 or any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts.
A copy of the license is included in the appendix entitled "GNU Free
Documentation License". 

1.5. New versions of this document

  Official New versions of this document can be found on the web pages of the
Linux Documentation Project Drafts and Beta versions will be available on in the appropriate sub folder. Changes to this document will
usually be discussed on the openMosix Mailing Lists. See the openMosix for

1.6. Feedback

 Currently this HOWTO is being maintained by Kris Buytaert. Please do send
remarks and updates for the howto to him.  

  If you have a technical question about openMosix/Mosix itself, please post
them on the more appropriate mailing list.

Chapter 2. So what is openMosix Anyway ?

2.1. A very, very brief introduction to clustering

  Most of the time, your computer is bored. Start a program like xload or top
that monitors your system use, and you will probably find that your processor
load is not even hitting the 1.0 mark. If you have two or more computers,
chances are that at any given time, at least one of them is doing nothing.
Unfortunately, when you really do need CPU power - during a C++ compile, or
encoding Ogg Vorbis music files - you need a lot of it at once. The idea
behind clustering is to spread these loads among all available computers,
using the resources that are free on other machines. 

  The basic unit of a cluster is a single computer, also called a "node".
Clusters can grow in size - they "scale" - by adding more machines. A cluster
as a whole will be more powerful the faster the individual computers and the
faster their connection speeds are. In addition, the operating system of the
cluster must make the best use of the available hardware in response to
changing conditions. This becomes more of a challenge if the cluster is
composed of different hardware types (a "heterogeneous" cluster), if the
configuration of the cluster changes unpredictably (machines joining and
leaving the cluster), and the loads cannot be predicted ahead of time.  

2.1.1. A very, very brief introduction to clustering HPC vs Fail-over vs Load-balancing

Basically there are 3 types of clusters, Fail-over, Load-balancing and HIGH
Performance Computing, The most deployed ones are probably the Failover
cluster and the Load-balancing Cluster. 

��*�Fail-over Clusters consist of 2 or more network connected computers with
    a separate heartbeat connection between the 2 hosts. The Heartbeat
    connection between the 2 machines is being used to monitor whether all
    the services are still in use: as soon as a service on one machine breaks
    down the other machines try to take over.
��*�With load-balancing clusters the concept is that when a request for say a
    web-server comes in, the cluster checks which machine is the least busy
    and then sends the request to that machine. Actually most of the times a
    Load-balancing cluster is also a Fail-over cluster but with the extra
    load balancing functionality and often with more nodes.
��*�The last variation of clustering is the High Performance Computing
    Cluster: the machines are being configured specially to give data centers
    that require extreme performance what they need. Beowulfs have been
    developed especially to give research facilities the computing speed they
    need. These kind of clusters also have some load-balancing features; they
    try to spread different processes to more machines in order to gain
    performance. But what it mainly comes down to in this situation is that a
    process is being parallelized and that routines that can be ran
    separately will be spread on different machines instead of having to wait
    till they get done one after another.

Most common known examples of loadbalancing and failover clusters are
webfarms, databases or firewalls. People want to have a 99,99999% uptime for
their services, the internet is open 24/24 7/7/ 365/365 not unlike in the old
days when you could shut down your server when the office closed.

People that are in need of cpu cycles often can afford to schedule downtime
for their environments, as long as they can use the maximum power of their
machines when they need it.
----------------------------------------------------------------------------- Supercomputers vs. clusters

 Traditionally Supercomputers have only been built by a selected number of
vendors: a company or organization that required the performance of such a
machine had to have a huge budget available for its Supercomputer. Lots of
universities could not afford the costs of a Supercomputer by themselves,
therefore other alternatives were being researched by them. The concept of a
cluster was born when people first tried to spread different jobs over more
computers and then gather back the data those jobs produced. With cheaper and
more common hardware available to everybody, results similar to real
Supercomputers were only to be dreamed of during the first years, but as the
PC platform developed further, the performance gap between a Supercomputer
and a cluster of multiple personal computers became smaller. 
----------------------------------------------------------------------------- Cluster models [(N)UMA, PVM/MPI]

There are different ways of doing parallel processing: (N)UMA, DSM, PVM and
MPI are all different kinds of Parallel Processing schemes. Some of them are
implemented in hardware, others in software, others in both.

(N)UMA ((Non-)Uniform Memory Access), machines for example have shared access
to the memory where they can execute their code. In the Linux kernel there is
a NUMA implementation that varies the memory access times for different
regions of memory. It then is the kernel's task to use the memory that is the
closest to the CPU it is using.

DSM aka Distributed Shared memory, has been implemented in both software and
hardware , the concept is to provide an abstraction layer for physically
distributed memory.

PVM and MPI are the tools that are most commonly being used when people talk
about GNU/Linux based Beowulfs.

MPI stands for Message Passing Interface. It is the open standard
specification for message passing libraries. MPICH is one of the most used
implementations of MPI. Next to MPICH you also can find LAM, another
implementation of MPI based on the free reference implementation of the

PVM or Parallel Virtual Machine is another cousin of MPI that is also quite
often being used as a tool to create a Beowulf. PVM lives in user space so no
special kernel modifications are required: basically each user with enough
rights can run PVM.  
----------------------------------------------------------------------------- openMosix's role

  The openMosix software package turns networked computers running GNU/Linux
into a cluster. It automatically balances the load between different nodes of
the cluster, and nodes can join or leave the running cluster without
disruption of the service. The load is spread out among nodes according to
their connection and CPU speeds. 

  Since openMosix is part of the kernel and maintains full compatibility with
Linux, a user's programs, files, and other resources will all work as before
without any further changes. The casual user will not notice the difference
between a Linux and an openMosix system. To her, the whole cluster will
function as one (fast) GNU/Linux system. 

openMosix is a Linux-kernel patch which provides full compatibility with
standard Linux for IA32-compatible platforms. The internal load-balancing
algorithm transparently migrates processes to other cluster members. The
advantage is a better load-sharing between the nodes. The cluster itself
tries to optimize utilization at any time (of course the sysadmin can affect
the automatic load-balancing by manual configuration during runtime).

This transparent process-migration feature makes the whole cluster look like
a BIG SMP-system with as many processors as available cluster-nodes (of
course multiplied with X for X-processor systems such as dual/quad systems
and so on). openMosix also provides a powerful optimized File System (oMFS)
for HPC-applications, which unlike NFS provides cache, time stamp and link

2.2. The story so far

2.2.1. Historical Development

 Rumours say that Mosix comes from Moshe Unix. Initially Mosix started out as
an application running on BSD/OS 3.0.
Announcing MO6 for BSD/OS 3.0                                                
Oren Laadan (                                            
Tue, 9 Sep 1997 19:50:12 +0300 (IDT)                                         
We are pleased to announce the availability of MO6 Version 3.0               
Release 1.04 (beta-4) - compatible with BSD/OS 3.0, patch level              
K300-001 through M300-029.                                                   
MO6 is a 6 processor version of the MOSIX multicomputer enhancements         
of BSD/OS for a PC Cluster. If you have 2 to 6 PC's connected by a           
LAN, you can experience truly multi-computing environment by using           
the MO6 enhancements.                                                        
The MO6 Distribution                                                         
MO6 is available either in "source" or "binary" distribution. It is          
installed as a patch to BSD/OS, using an interactive installation            
MO6 is available at                   
or at our site:                              
Main highlights of the current release:                                      
- Memory ushering (depletion prevention) by process migration.               
- Improved installation procedure.                                           
- Enhanced migration control.                                                
- Improved administration tools.                                             
- More user utilities.                                                       
- More documentation and new man pages.                                      
- Dynamic configurations.                                                    
Please send feedback and comments to                    
GNU/Linux was chosen as a development platform for the 7th incarnation in
1999. Early 1999 Mosix M06 Beta was released for Linux 2.2.1 At the end of
2001 and early 2002 openMosix, the open version of Mosix was born (more in
the next paragraph).

2.2.2. openMosix

openMosix is in addition to whatever you find at and in full
appreciation and respect for Prof. Barak's leadership in the outstanding
Mosix project.

Moshe Bar has been involved for a number of years with the Mosix project
( and was co-project manager of the Mosix project and general
manager of the commercial Mosix company.

After a difference of opinions on the commercial future of Mosix, he has
started a new clustering company - Qlusters, Inc. - and Prof. Barak has
decided not to participate for the moment in this venture (although he did
seriously consider joining) and held long running negotiations with
investors. It appears that Mosix is not any longer supported openly as a GPL
project. Because there is a significant user base out there (about 1000
installations world-wide), Moshe Bar has decided to continue the development
and support of the Mosix project under a new name: openMosix and under the
full GPL2 license. Whatever code in openMosix comes from the old Mosix
project is Copyright 2002 by Amnon Barak. All the new code is Copyright 2002
by Moshe Bar.

There could (and will) be significant changes in the architecture of the
future openMosix versions. New concepts about auto-configuration,
node-discovery and new user-land tools are being discussed in the openMosix
mailing lists. Most of these new functionalities are already implemented
while some of them, such as DSM (Distributed Shared Memory) are still being
worked on at the moment I write this (march 2003).

To approach standardization and future compatibility the proc-interface has
changed from /proc/mosix to /proc/hpc and the /etc/ was changed to /
etc/ More recently the standard for the config file has been set to
be located in /etc/ (this is in fact the first config file the /
etc/init.d/openmosix script will look for). Adapted command-line user-space
tools for openMosix are already available on the web-page of the project.

The config file can be replaced with a node-auto-discovery
system which is called omdiscd (openMosix auto DISCovery Daemon) about which
we will discuss later.

openMosix is supported by various competent people (see working together around the world. The main goal
of the project is to create a standardized clustering-environment for all
kinds of HPC-applications.

openMosix has also a project web-page at
with a CVS tree and mailing-lists for developers as well as users.

2.2.3. Current state

Like most active Open Source programs, openMosix's rate of change tends to
outstrip the followers' ability to keep the documentation up to date.

As I write this part in February 2003 openMosix 2.4.20 is available and
openMosix Userland Tools v0.2.4 are available, including the new
autodiscovery tools.

For a more recent state of development please take a look at the openMosix

2.2.4. Which applications work

It is almost impossible to give a list off all the applications that work
with openMosix. The community however tries to keep track of the applications
that migrate and the ones who don't.

2.3. openMosix in action: An example

  openMosix clusters can take various forms. To demonstrate this, let's
assume you are a student and share a dorm room with a rich computer science
guy, with whom you have linked computers to form an openMosix cluster. Let's
also assume you are currently converting music files from your CDs to Ogg
Vorbis for your private use, which is legal in your country. Your roommate is
working on a project in C++ that he says will bring World Peace. However, at
just this moment he is in the bathroom doing unspeakable things, and his
computer is idle. 

  So when you start a program like bladeenc to convert Bach's .... from .wav
to .ogg format, the openMosix routines on your machine compare the load on
both nodes and decide that things will go faster if that process is sent from
your Pentium-233 to his Athlon XP. This happens automatically: you just type
or click your commands as you would if you were on a standalone machine. All
you notice is that when you start two more coding runs, things go a lot
faster, and the response time doesn't go down. 

  Now while you're still typing ...., your roommate comes back, mumbling
something about red chili peppers in cafeteria food. He resumes his tests,
using a program called 'pmake', a version of 'make' optimized for parallel
execution. Whatever he's doing, it uses up so much CPU time that openMosix
even starts to send subprocesses to your machine to balance the load. 

  This setup is called *single-pool*: all computers are used as a single
cluster. The advantage/disadvantage of this is that your computer is part of
the pool: your stuff will run on other computers, but their stuff will run on
yours too. 

2.4. Components

2.4.1. Process migration

 With openMosix you can start a process on one machine and find out it
actually runs on another machine in the cluster. Each process has its own
Unique Home Node (UHN) where it gets created.

 Migration means that a process is splitted in 2 parts, a user part and a
system part. The user part will be moved to a remote node while the system
part will stay on the UHN. This system-part is sometimes called the deputy
process: this process takes care of resolving most of the system calls.

openMosix takes care of the communication between these 2 processes.

2.4.2. The openMosix File System (oMFS)

oMFS is a feature of openMosix which allows you to access remote filesystems
in a cluster as if they were locally mounted. The filesystems of your other
nodes can be mounted on /mfs and you will, for instance, find the files in /
home on node 3 on each machine in /mfs/3/home. 

2.4.3. Direct File System Access (DFSA)

Both Mosix and openMosix provide a cluster-wide file-system (MFS) with the
DFSA-option (Direct File-System Access). It provides access to all local and
remote file-systems of the nodes in a Mosix or openMosix cluster.

2.5. openMosix Test Drive

In support of openMosix, Major Chai Mee Joon is giving OM users a free trial
account to his online openMosix cluster service, which users can use to test
and experiment openMosix with.

The availability of this online openMosix cluster service will help both new
users overcome the initial openMosix configuration issues, and also provides
higher computing power to openMosix users who are developing or porting their

Please send an email to <> for a trial account. 

2.6. Pros of openMosix

Table 2-1. Pros of openMosix
|No extra packages are required.                                            |
|No code changes to your application are required.                          |
|Simple to install/configure.                                               |
|On a Red-Hat based system/distro, installing openMosix is as simple as     |
|typing: # rpm -Uvh openMosix*.rpm                                          |
|DSM is being released soon (late march 2003).                              |
|Well integrated with openAFS.                                              |
|Port to IA-64 as well as AMD-64 is underway.                               |
|oMFS has been improved much since plain MFS.                               |
|It is a clustering platform with more than 10 products based on it:        |
|openMosixView, openMosixWebView, openMosixApplet, RxLinux, PlumpOS,        |
|K12LTSP, LTSP and many others.                                             |
|openMosix is a product developed by the users themselves so it's more close|
|to the user by definition.                                                 |
|Node autodiscovery/fail-over daemon already implemented in the user land   |
|tools via multicast messaging.                                             |
|Aliases for hosts with multiple interfaces.                                |
|Basic routing available (in the rare case where true multicast routing is  |
|undesirable).                                                              |
|Cluster Mask allows to specify to which nodes a given process can migrate. |

2.7. Cons of openMosix

Table 2-2. Cons of openMosix
|Kernel dependent.                                                          |
|Shared memory issues (an alpha release of DSM should be available as of    |
|late march 2003).                                                          |
|There are issues with Multiple Threads not gaining performance.            |
|You won't gain performance when running one single process such as your web|
|browser on an openMosix Cluster: the process won't spread itself over the  |
|cluster. Except of course your process will migrate to a more performant   |
|machine.                                                                   |

II. Installing openMosix

Table of Contents
3. Requirements and Planning
    3.1. Hardware requirements
    3.2. Hardware Setup Guidelines
    3.3. Software requirements
    3.4. Planning your Cluster
    3.5. Classrooms
4. Distribution specific installations
    4.1. Installing openMosix
    4.2. Before getting openMosix
    4.3. Getting openMosix
    4.4. openMosix General Instructions
    4.5. Red Hat and openMosix
    4.6. Suse and openMosix
    4.7. Debian and openMosix
    4.8. openMosix and Gentoo
    4.9. Other distributions
5. Autodiscovery
    5.1. Easy Configuration
    5.2. Compiling auto-discovering
    5.3. Troubleshooting autodiscovery
6. PlumpOS
    6.1. What Plump/OS is
    6.2. How does it work?
    6.3. Requirements
    6.4. Getting Started
7. Cluster Installation
    7.1. Cluster Installations
    7.2. DSH, Distributed Shell

Chapter 3. Requirements and Planning

3.1. Hardware requirements

Installing a basic cluster requires at least 2 network connected machines,
either using a cross-cable between the two network cards or using a switch or
hub (a switch is much better than a hub though and only costs a few bucks
more). Of course the faster your network-cards the easier you will get better
performance for your cluster.

These days Fast Ethernet (100 Mbps) is standard; putting multiple ports in a
machine isn't that difficult, but make sure to connect them through other
physical networks in order to gain the speed you want. Gigabit Ethernet is
getting cheaper every day now but I suggest that you don't rush to the shop
spending your money before you have actually tested your setup with multiple
100Mbit cards and noticed that you really do need the extra network capacity.
Next to putting a Gigabit card you might also want to try bonding different
100Mbit cards together. An even cheaper alternative can be found in Firewire,
as discussed in this paper

3.2. Hardware Setup Guidelines

Setting up a big cluster requires some thinking to be done: where are you
going to put the machines? Not under a table somewhere or in the middle of
your office I hope! It's ok if you just want to do some small tests, but if
you are planning to deploy a N node cluster you will have to make sure that
the environment that will hold these machines is capable of doing so.

I'm talking about preparing one or more 19" racks to host the machines,
configuring the appropriate network topology, either straight, single
connected or even a 1 to 1 cross connected network between all your nodes.
You will also need to make sure that there is enough power to support such a
range of machines, that your air-conditioning system supports the load and
that in case of power-failure your UPS can cleanly shut down all the required
systems. You might want to invest in a KVM (Keyboard, Video, Mouse) Switch in
order to facility access to the machines' consoles.

But even if you don't have the number of nodes that justifies such an
investment, make sure that you can always easily access the different nodes,
you never know when you have to replace a CPU fan or an hard-disk of a
machine in trouble. If that means that you have to unload a stack of machines
to reach the bottom one, hence shutting down your cluster, you are in

3.3. Software requirements

The systems we plan to use will need a basic Linux installation of your
choice: Red Hat, SuSe, Debian, Gentoo or any another distribution: it doesn't
really matter which one. What does matter is that the kernel is at least on
2.4 level, and that your network-cards are configured correctly; next to that
you'll need a healthy space of swap.

3.4. Planning your Cluster

When it comes to configuring openMosix Clusters with a pool of servers and a
set of (personal) workstations, you have different options that will have
their advantages and disadvantages.

��*�In a Single-pool configuration all the servers and workstations are used
    as a single cluster: each machine is a part of the cluster and can
    migrate processes to each other existing node. This of course makes your
    workstation a part of the pool.
��*�In an environment that is called a Server-pool, servers are a part of the
    cluster while workstations aren't part of it, they don't even have
    openMosix kernel. If you want to run applications on the cluster you will
    need to specifically log on to these servers. However your workstation
    will also stay clean and no remote processes will migrate to it.
��*�A third alternative is called an Adaptive-pool configuration: here
    servers are shared while workstations join or leave the cluster. Imagine
    your workstation being used during daytime by yourself but, as soon as
    you log out in the evening, a script tells the workstation to join the
    cluster and start crunching numbers. This way your machine is being used
    while you don't need it. If you need the resources of the machine again
    just run the openmosix stop script and your processes will stay away from
    the cluster and vice-versa.
    Practically this means that you will change the role of your machine by
    using mosctl.

3.5. Classrooms

Although it might seem a good idea to convert your classroom into an
openMosix cluster at night, you'll have to consider training your end users
not to pull the power switch of those machines when they want to use them
again. More recent machines support automatic shutdowns when hitting the
power button, but with older machines you might loose some data when this
actually happens.

Chapter 4. Distribution specific installations

4.1. Installing openMosix

This chapter deals with installing openMosix on different distributions. It
won't be an exhaustive list of all the possible combinations. However
throughout the chapter you should find enough information on installing
openMosix in your environment.

Techniques for installing multiple machines with openMosix will be discussed
in one of the next chapters.

4.2. Before getting openMosix

First of all, you must understand that openMosix is made up of a kernel patch
and some user-space tools. The kernel patch is needed to make the kernel
capable of talking to other openMosix-enabled machines on the network. If you
download openMosix as a binary package (such as an rpm file), you don't even
need to take care about the kernel patch because the kernel has been patched
and compiled with the most common default options and modules for you.

The user-space tools are needed in order to make an effective use of an
openMosix-enabled kernel. They are needed to start/stop the migration daemon,
the openMosix File System, to migrate jobs to certain nodes and other tasks
which are usually accomplished with the help our good old friend: the command
line interface. About binary packages: the same as in the kernel patch goes
for the user-space tools: if you install an rpm you don't need to care about
compiling them or configuring anything; just let them install and run. That's
all. Really :)

Once you get to the download page (which we'll talk about in a second),
you'll need to get two distinct parts: the kernel and the user-space tools.
You can either download two binary packages or get the kernel patch plus the
user-space tools' sources. The kernel patch is usually named after this
scheme: openMosix-x.y.z-w where x.y.z is the version of the vanilla Linux
Kernel against which the patch should be applied and w is the patch revision
for that particular kernel release. For the precompiled kernel binaries,
please refer to the README-openMosix-kernel.txt file you'll find in the
download page. This file also contains updated info about manually compiling
a kernel.

About the user-space tools: you'll find those in a package named
openmosix-tools. We use the terms user-space tools, userspace-tools and
openmosix-tools interchangeably. Updated info about precompiled binaries and
manually compiling the tools are also provided in the
README-openmosix-tools.txt file. Please note that since version 0.3 of the
openmosix-tools, the file is deprecated and the use of the
autodiscovery daemon is highly encouraged since it tends to make your life

4.3. Getting openMosix

You can download the latest versions of openMosix from
/project/showfiles.php?group_id=46729. You can either choose the binary (even
in rpm) compiled for UP or SMP or download the source code. You will need
both the kernel patch or binaries and the userland tools. Alternatively you
can get the CVS version:
cvs login                  
cvs -z3 co linux-openmosix 
cvs -z3 co userspace-tools 
At the password prompt, just type enter since you're doing an anonymous
login. Please take care that CVS trees DO BREAK now and then and that it
might not be the easiest way to install openMosix ;-) 

4.4. openMosix General Instructions

4.4.1. Kernel Compilation

 Always use pure vanilla kernel-sources from to
compile an openMosix kernel! Please be kind enough to download the kernel
using a mirror near to you and always try and download patches to the latest
kernel sources you do have instead of downloading the whole thing. This is
going to be much appreciated by the Linux community and will greatly increase
your geeky Karma ;-) Be sure to use the right openMosix patch depending on
the kernel-version. At the moment I write this, the latest 2.4 kernel is
2.4.20 so you should download the openMosix-2.4.20-x.gz patch, where the "x"
stands for the patch revision (ie: the greater the revision number, the most
recent it is). Do not use the kernel that comes with any Linux-distribution:
it won't work. These kernel sources get heavily patched by the
distribution-makers so, applying the openMosix patch to such a kernel is
going to fail for sure! Been there, done that: trust me ;-)

Download the actual version of the openMosix patch and move it in your
kernel-source directory (e.g. /usr/src/linux-2.4.20). If your kernel-source
directory is other than "/usr/src/linux-[version_number]" at least the
creation of a symbolic link to "/usr/src/linux-[version_number]" is required.
Supposing you're the root user and you've downloaded the gzipped patch file
in your home directory, apply the patch using (guess what?) the patch
mv /root/openMosix-2.4.20-2.gz /usr/src/linux-2.4.20                         
cd /usr/src/linux-2.4.20                                                     
zcat openMosix-2.4.20-2.gz | patch -Np1                                      
In the rare case you don't have "zcat" on your system, do:
mv /root/openMosix-2.4.20-2.gz /usr/src/linux-2.4.20                         
cd /usr/src/linux-2.4.20                                                     
gunzip openMosix-2.4.20-2.gz                                                 
cat openMosix-2.4.20-2 | patch -Np1                                          
If the even more weird case you don't have a "cat" on your system (!), do:
mv /root/openMosix-2.4.20-2.gz /usr/src/linux-2.4.20                         
cd /usr/src/linux-2.4.20                                                     
gunzip openMosix-2.4.20-2.gz                                                 
patch -Np1 < openMosix-2.4.20-2                                              
The "patch" command should now display a list of patched files from the
kernel-sources. If you feel adventurous enough, enable the openMosix related
options in the kernel-configuration file, e.g.
# CONFIG_MOSIX_TOPOLOGY is not set                                           
# CONFIG_MOSIX_DEBUG is not set                                              
# CONFIG_MOSIX_CHEAT_MIGSELF is not set                                      
However, it's going to be pretty much easier if you configure the above
options using one of the Linux-kernel configuration tools:
make config | menuconfig | xconfig                                           
The above means you have to choose one of "config", "menuconfig", and
"xconfig". It's a matter of taste. By the way, "config" is going to work on
any system; "menuconfig" needs the curses libraries installed while "xconfig"
needs an installed X-window environment plus the TCL/TK libraries and

Now compile it with:
make dep bzImage modules modules_install                                     
After compilation install the new kernel with the openMosix options within
you boot-loader; e.g. insert an entry for the new kernel in /etc/lilo.conf
and run lilo after that.

Reboot and your openMosix-cluster-node is up!

4.4.2. Syntax of the /etc/ file

Before starting openMosix, there has to be an /etc/
configuration file which must be the same on each node.

The standard is now /etc/, /etc/ and /etc/ are
old standards, but the CVS-version of the tools is backwards compatible and
looks for /etc/, /etc/ and /etc/ (in that

The file contains three space separated fields:
openMosix-Node_ID               IP-Address(or hostname)          Range-size  
An example file could look like this:
1       node1   1                                                            
2       node2   1                                                            
3       node3   1                                                            
4       node4   1                                                            
1     1                                                    
2     1                                                    
3     1                                                    
4     1                                                    
or with the help of the range-size both of the above examples equal to:
1     4                                                    
openMosix "counts-up" the last byte of the ip-address of the node according
to its openMosix-Node_ID. Of course, if you use a range-size greater than 1
you have to use ip-addresses instead of hostnames.

If a node has more than one network-interface it can be configured with the
ALIAS option in the range-size field (which equals to setting the range-size
to 0) e.g.
1     1                                                    
2     1                                                    
3     1                                                    
4     1                                                    
4   ALIAS                                                
Here the node with the openMosix-Node_ID 4 has two network-interfaces
( + which are both visible to openMosix.

Always be sure to run the same openMosix version AND configuration on each of
your Cluster's nodes!

Start openMosix with the "setpe" utility on each node :
setpe -w -f /etc/                                               
Execute this command (which will be described later on in this HOWTO) on
every node in your openMosix cluster.

Alternatively, you can grab the "openmosix" script which can be found in the
scripts directory of the userspace-tools, copy it to the /etc/init.d
directory, chmod 0755 it, then use the following commands as root:
/etc/init.d/openmosix stop                                                   
/etc/init.d/openmosix start                                                  
/etc/init.d/openmosix restart                                                

Installation is finished now: the cluster is up and running :)

4.4.3. oMFS

First of all, the CONFIG_MOSIX_FS option in the kernel configuration has to
be enabled. If the current kernel was compiled without this option, then
recompilation with this option enabled is required.

Also the UIDs (User IDs) and GIDs (Group IDs) on each of the clusters' nodes
file-systems must be the same. You might want to accomplish this using
openldap. The CONFIG_MOSIX_DFSA option in the kernel is optional but of
course required if DFSA should be used. To mount oMFS on the cluster there
has to be an additional fstab-entry on each node's /etc/fstab.

in order to have DFSA enabled:
mfs_mnt         /mfs            mfs     dfsa=1          0 0                  
in order to have DFSA disabled:
mfs_mnt          /mfs           mfs     dfsa=0          0 0                  
the syntax of this fstab-entry is:
[device_name]           [mount_point]   mfs     defaults        0 0          
After mounting the /mfs mount-point on each node, each node's file-system is
going to be accessible through the /mfs/[openMosix-Node_ID]/ directories.

With the help of some symbolic links all cluster-nodes can access the same
data e.g. /work on node1
on node2 :      ln -s /mfs/1/work /work                                      
on node3 :      ln -s /mfs/1/work /work                                      
on node3 :      ln -s /mfs/1/work /work                                      
Now every node can read+write from and to /work !

 The following special files are excluded from the oMFS:

��*�the /proc directory
��*�special files which are not regular-files, directories or symbolic links
    (e.g. /dev/hda1)

Creating links like:
ln -s /mfs/1/mfs/1/usr                                                       
ln -s /mfs/1/mfs/3/usr                                                       
is invalid.

The following system calls are supported without sending the migrated process
(which executes this call on its home (remote) node) going back to its home

read, readv, write, writev, readahead, lseek, llseek, open, creat, close,
dup, dup2, fcntl/fcntl64, getdents, getdents64, old_readdir, fsync,
fdatasync, chdir, fchdir, getcwd, stat, stat64, newstat, lstat, lstat64,
newlstat, fstat, fstat64, newfstat, access, truncate, truncate64, ftruncate,
ftruncate64, chmod, chown, chown16, lchown, lchown16, fchmod, fchown,
fchown16, utime, utimes, symlink, readlink, mkdir, rmdir, link, unlink,

Here are situations when system calls on DFSA mounted file-systems may not

��*�different mfs/dfsa configuration on the cluster-nodes
��*�dup2 if the second file-pointer is non-DFSA
��*�chdir/fchdir if the parent dir is non-DFSA
��*�pathnames that leave the DFSA-filesystem
��*�when the process which executes the system-call is being traced
��*�if there are pending requests for the process which executes the

Next to the /mfs/1/ /mfs/2/ and so on files you will find some other
directories as well.

Table 4-1. Other Directories
|/mfs/   |The current node where your process runs                          |
|here    |                                                                  |
|/mfs/   |Your home node                                                    |
|home    |                                                                  |
|/mfs/   |The current node when used by the "creat" system call (or an      |
|magic   |"open" with the "O_CREAT" option) - otherwise, the last node on   |
|        |which an oMFS magical file was successfully created (this is very |
|        |useful for creating temporary-files, then immediately unlinking   |
|        |them)                                                             |
|/mfs/   |The node on which the process last issued a successful "execve"   |
|lastexec|system-call.                                                      |
|/mfs/   |The node you selected by either your process itself or one of its |
|selected|ancestor's (before forking this process), writing a number into "/|
|        |proc/self/selected".                                              |

 Note that these magic files are all ``per process''. That is their content
is dependent upon which process opens them.

A last not about openMFS is that there are versions around that return
faultive results when you run "df" on those filesystems. Don't be surpised if
you suddenlty have about 1.3 TB available on those systems.

4.5. Red Hat and openMosix

If you are running a RedHat 7.2, 7.3 or 8.0 version, this is probably the
easiest *Mosix install you have ever done. Choose the appropriate openMosix
RPMs from sourceforge. They have precompiled kernels (as I write this 2.4.20)
that work seamlessly: I have tested them on several machines including
Laptops with PCMCIA cards and Servers with SCSI disks. If you are a grub
user, the kernel rpm even modifies your grub.conf. So all you have to do is
install 2 RPMs:
rpm -Uvh openmosix-kernel-2.4.20-openmosix2.i686.rpm openmosix-tools-0.2.4-1.i386.rpm
and edit your /etc/ if you don't wish to use the autodiscovery
daemon (omdiscd). Since this seems to be a problem for lots of people, let's
go with another example. Say you have 3 machines:, and Your will look like this.
[root@oscar0 root]# more /etc/                                          
# openMosix CONFIGURATION                                                            
# ===================                                                                
# Each line should contain 3 fields, mapping IP addresses to openMosix node-numbers: 
# 1) first openMosix node-number in range.                                           
# 2) IP address of the above node (or node-name from /etc/hosts).                    
# 3) number of nodes in this range.                                                  
# Example: 10 machines with IP -                           
# 1     10                                                       
# openMosix-#  IP  number-of-nodes                                                   
# ============================                                                       
1 1                                                                   
2  1                                                                   
3  1                                                                   
Now by rebooting the different machines with the newly installed kernel you
will get one step closer to having a working cluster.

Most RedHat installations have one extra thing to fix. You often get the
following error:
[root@inspon root]# /etc/init.d/openmosix start                              
Initializing openMosix...                                                    
setpe: the supplied table is well-formatted,                                 
but my IP address ( is not there!                                  
This means that your hostname is not listed in /etc/hosts with the same ip as
in your You might have a machine called
in your hostfile listed as localhost                              
If you modify your /etc/hosts to look like below, openMosix will have less
troubles starting up.                                      localhost                                                    
[root@inspon root]# /etc/init.d/openmosix start                              
Initializing openMosix...                                                    
[root@inspon root]# /etc/init.d/openmosix status                             
This is openMosix node #2                                                    
Network protocol: 2 (AF_INET)                                                
openMosix range     1-1     begins at                         
openMosix range     2-2     begins at                    
openMosix range     3-3     begins at                          
Total configured: 3                                                          

If you would like to use more bleeding edge patches, you can always opt for
the src rpm and run rpmbuild --rebuild on it. This will install the source
for you and create an initial config file. From there you can go further
applying patches to openMosix

A tutorial on how to build your own openMosix RPM's can be found in the

As new RedHat versions come out, they might be supported out of the box so,
feel free to drop the author a note and help him keeping this information

4.6. Suse and openMosix

Although the RPMs are being built on a RedHat based environment, you can use
most of them on other RPM based systems.

Suse however has /sbin/mk_initrd as a link to /sbin/mkinitrd, which makes
rpms before release 20-2 fail. Newer version should have a fix for this.

4.7. Debian and openMosix

Installing openMosix ``the Debian way'' can be easily done as described

The first step consists in downloading the packages from the net. I had to
use a 2.4.19 kernel since the openMosix patches package is not yet available
for 2.4.20 at the moment I write this. Since we are using a Debian setup we
needed:, http://, http://, http:// You can also
apt-get install them ;).

 The next part is making the kernel openMosix capable.

Basically, the procedure to follow is:
cd /usr/src                                                                  
apt-get install kernel-source-2.4.19 kernel-package \                        
        openmosix kernel-patch-openmosix                                     
tar vxjf kernel-source-2.4.19.tar.bz2                                        
ln -s /usr/src/kernel-source-2.4.19 /usr/src/linux                           
cd /usr/src/linux                                                            
make menuconfig                                                              
make-kpkg kernel_image modules_image                                         
cd ..                                                                        
dpkg -i kernel-image-*-openmosix-*.deb                                       
You now will need to edit your /etc/ Please follow the
instructions given in the ``Syntax of /etc/'' part of this

After rebooting with this kernel and a configured /etc/, you
should then have a cluster of openMosix machines that talk to each-other and
that do migration of processes.

 You can test that by running the following small script:
awk 'BEGIN {for(i=0;i<10000;i++)for(j=0;j<10000;j++);}'                      
a couple of times, and monitor its behaviour with "mosmon" where you will see
that it spreads the load between the different nodes.

We also setup openMosixView on the Debian machine:
apt-get install openmosixview                                                
In order to be able to actually use openMosixView you will need to run it
from a user who can log in to the different nodes as root. We suggest you set
this up using ssh. Please note that there is a difference between the ssh and
ssh2 implementations. If you do have an file, ssh will check
authorized_keys, while if you do have an you will need

 openMosixView gives you a nice interface that shows the load of different
machines and gives you the possibility to migrate processes manually.

A detailed discussion of openMosixView can be found elsewhere in this

4.8. openMosix and Gentoo

First Install Gentoo Linux

Then, install openMosix: type "emerge sys-apps/openmosix-user", which will
install an openMosix kernel source tree in /usr/src/linux along with the
openMosix userland tools.

Michael Imhof, aka tantive, keeps Gentoo current for the latest openMosix

Daniel Robbins, the President/CEO of Gentoo Technologies, Inc. and the
creator of Gentoo Linux, wrote the artitles we use as our Introduction to
openMosix Clusters.

4.9. Other distributions

Based on the explanations above you should be able to install openMosix on
most other Linux platforms.

Chapter 5. Autodiscovery

5.1. Easy Configuration

The auto-discovery daemon (omdiscd) provides a way to automatically configure
an openMosix cluster hence eliminating the need of a /etc/ or
similar manual configurations. Auto-discovery uses multicast packages to
notify other nodes that it is an openMosix node. This way adding an extra
node to your mosix cluster means that you just have to start the omdiscd on
your machine and it will join the cluster.

 However there are some small requirements, Like with any openMosix cluster ,
you need to have networking configured correctly. mainly the routing. Without
a default route, you must specify an interface to omdiscd with the -i option.
Otherwise omdiscd will exit with an error like.
Aug 31 20:41:49 localhost omdiscd[1290]: Unable to determine address of      
default interface.  This may happen because there is no default route        
configured.  Without a default route, an interface must be: Network is       
Aug 31 20:41:49 localhost omdiscd[1290]: Unable to initialize network.       
An example of a correct routing is below
[root@localhost log]# route -n                                                
Kernel IP routing table                                                       
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface       U     0      0        0 eth0       U     0      0        0 lo         UG    0      0        0 eth0  
Basically from now on everything will get easier. Just start
And have a look at your logfiles you should see something similar to this
Sep  2 10:00:49 oscar0 kernel: openMosix configuration changed: This is openMosix #2780 (of 6 configured) 
Sep  2 10:00:49 oscar0 kernel: openMosix #2780 is at IP address                            
Sep  2 10:00:49 oscar0 kernel: openMosix #2638 is at IP address                             
Sep  2 10:00:49 oscar0 kernel: openMosix #2646 is at IP address                             
Sep  2 10:00:49 oscar0 kernel: openMosix #2627 is at IP address                             
Sep  2 10:00:49 oscar0 kernel: openMosix #2634 is at IP address                             
Congratulations , your openMosix cluster is now working.

omdiscd has some other options that you can use. You can either run omdiscd
as a daemon (default) or in the foreground where output goes to the screen
(standard output) omdiscd -n . An interface can be specified with the -i

 Now lets still have a short look at the other tool , it's showmap. This tool
will show you the newly auto generated openMosix map.
[root@oscar0 root]# showmap                                                  
My Node-Id: 0x0adc                                                           
Base Node-Id Address          Count                                          
------------ ---------------- -----                                          
0x0adc   1                                              
0x0a4e    1                                              
0x0a56    1                                              
0x0a43    1                                              
0x0a4a    1                                              

Auto-discovery has some other features not listed here such as a routing
mechanism for clusters with more than one network. More detailed information
can be found in the README and DESIGN files in the user-land tools source

More recent versions of the openMosix rc scripts will first verify wether an
/etc/ file or similar exists before trying to use

5.2. Compiling auto-discovering

If you are compiling autodiscovery from source you will need to make a small
modification to openmosix.c. One of the first lines will be
#define ALPHA                                                                
You will need to put this in comment. If you want to have some more logging
available to you you should edit main.c to show log_set_debug
(DEBUG_TRACE_ALL); (somewhere around line 84) now run
% make clean                                                                 
% make                                                                       

5.3. Troubleshooting autodiscovery

Sometimes however autodiscovery does not function as you would like, for
example a node might not see multicast traffic from other nodes. This has
occurred with some PCMCIA ethernet drivers. One solution is to place the
interface in promiscuous and or multicast mode as detailed below:
Aug 31 20:45:58 localhost kernel: openMosix configuration changed: This is openMosix #98 (of 1 configured)                                      
Aug 31 20:45:58 localhost kernel: openMosix #98 is at IP address 31 20:45:58 localhost omdiscd[1627]: Notified kernel to activate  
openMosix  Aug 31 20:45:58 localhost kernel: Received an unauthorized information request from                                        
What you should to then is try to force your NIC into promiscuous and/ or
multicast mode manually.
ifconfig ethx promisc                                                        
ifconfig ethx multicast                                                      
You might also want to run
tcpdump -i eth0 ether multicast                                              
which will have the same effect but you will now also be able to see the
packages yourself. 

On some Layer 3 switches you other configs might be required. An openMosix
user found out that on his Switch Summit48Si (Extreme Networks) he had to run
disable ipmcforwarding (to deactivate the routing of multicast paquets)      
disable igmp snooping                                                        
before he was the different omdiscd's were able to see eachother, other
switches might require similar configs.

Aug 31 22:14:43 inspon omdiscd[1422]: Simulated notification to activate openMosix 
[root@inspon root]# showmap                                                        
My Node-Id: 0x0063                                                                 
Base Node-Id Address          Count                                                
------------ ---------------- -----                                                
0x0063        1                                                    
[root@inspon root]# /etc/init.d/openmosix status                                   
OpenMosix is currently disabled                                                    
[root@inspon root]#                                                                
If you see the simulated you have probably forgotten to put the
#define ALPHA                                                                
in comment.

I have also noticed that autodiscovery does not work with FireWire based
network cards.

Chapter 6. PlumpOS

6.1. What Plump/OS is

PlumpOS is a CD-based GNU/Linux/openMosix mini-distribution designed to allow
users to quickly, or temporarily, add nodes to an openMosix cluster; as I
write this in march 2003 the version (release 6.9 RC1) is a 16.7M ISO

This chapter is a quick hack up by Peter Willis of a very similar chapter
contributed by Jean-David Marrow (who is the author of Clump/OS and inspirer
of PlumpOS - props to Jean-David for his fine work on the departed Clump/OS).

6.2. How does it work?

First of all, set up your machine's BIOS in order to make it boot from CD.
Check your motherboard's manual to see how to set up this. Upon booting up
you will receive a prompt to boot PlumpOS using a specific kernel; several
ones have been provided for you but, you also have the option of providing
your own kernel + modules. This will be explained later in the ``Getting
Started'' section. The boot menu should tell you all the kernels available
for you to use; simply type the name of one (and optionally some kernel
arguments) and press return/enter.

At boot-time, PlumpOS will auto-probe for network cards and, if any gets
detected, it'll try and configure them via DHCP. If successful, it will fire
up omdiscd on each interface a DHCP lease is received on. Currently this has
only been tested in PCs with 1 network card so YMMV.

It works for myself, but may not work for you; if you experience
difficulties, please email me with as much information about your system as
possible -- after you have investigated the problem. (Check the sourceforge
homepage for PlumpOS's mailing list, sign up and post your question with as
much detailed information as possible. The openMosix-general and
openMosix-devel lists are NOT for PlumpOS problems, they are for
openMosix-specific problems, and if you can't tell the difference just send
it to the PlumpOS list or my contact email).

6.3. Requirements

As the purpose of PlumpOS is to add nodes to a cluster, it is assumed that
you already have a running openMosix cluster -- or perhaps only a single
openMosix node -- from which you will be initiating jobs. All machines in the
cluster must conform to the following requirements:

��*�PlumpOS Machine(s) 586+ CPU
��*�bootable CD-ROM drive
��*�Network Interface Card
��*�Between 32M and 128M of RAM. Because of some oddities in the openMosix
    kernels at the time of this writing, simply passing the size of the
    ramdisk is not working so one has to actually use a ramdisk pre-made for
    a specific size. There should be several ramdisks avaliable at PlumpOS
    mirrors which can be placed in the disks' root directory on the actual
    cdrom ISO (or rootdisk/disks/ if you're inside the PlumpOS package
��*�Master Machine(s) GNU/Linux/openMosix kernel (same version as all the
    PlumpOS kernel you are booting on the Child/Slave PlumpOS Machine(s))
��*�Network Environment Running DHCP server (if you don't, or won't, run
    DHCP, you can still manually configure your system: simply go to each
    PlumpOS machine and enter in your desired configuration information with
    the supplied networking tools. Using DHCP is highly recommended however,
    and will greatly simplify your life in the long run.

The following network modules are present in most if not all of the supplied
kernels' modules tarball (in /kernels/KERNELNAME/modules.tgz), although not
all support auto-probing; if you don't see support for your card in this
list, then PlumpOS will not work for you.

3c501.o, 3c503.o, 3c505.o, 3c507.o, 3c509.o, 3c515.o, 3c59x.o, 8139cp.o,
8139too.o, 82596.o, ac3200.o, acenic.o, aironet4500_card.o,
aironet4500_core.o, aironet4500_proc.o, arlan-proc.o, arlan.o, at1700.o,
bsd_comp.o, cs89x0.o, de4x5.o, depca.o, dgrs.o, dl2k.o, dmfe.o, dummy.o, e100
/e100.o, e1000/e1000.o, e2100.o, eepro.o, eepro100.o, eexpress.o, epic100.o,
eth16i.o, ewrk3.o, fealnx.o, hamachi.o, hp-plus.o, hp.o, hp100.o, lance.o,
lp486e.o, mii.o, natsemi.o, ne.o, ne2k-pci.o, ni5010.o, ni52.o, ni65.o,
ns83820.o, pcmcia, pcnet32.o, ppp_async.o, ppp_deflate.o, ppp_generic.o,
ppp_synctty.o, pppoe.o, pppox.o, sis900.o, sk98lin/sk98lin.o, slhc.o,
smc-ultra.o, smc9194.o, starfire.o, strip.o, sundance.o, sungem.o, sunhme.o,
tc35815.o, tg3.o, tlan.o, tokenring/{3c359.o abyss.o ibmtr.o lanstreamer.o
olympic.o smctr.o tms380tr.o tmsisa.o tmspci.o}, tulip/tulip.o, via-rhine.o,
wavelan.o, wd.o, winbond-840.o, wireless/{airo.o airo_cs.o hermes.o orinoco.o
orinoco_cs.o orinoco_pci.o orinoco_plx.o}, yellowfin.o

Please also note that PlumpOS may not work on a laptop: it definitely doesn't
support PCMCIA cards (yet), and will probably not configure openMosix
properly if your machine contains multiple connected Ethernet adapters. This
is a temporary limitation of the configuration scripts, and should be
resolved in future releases.

6.4. Getting Started

You can download the latest PlumpOS package under the terms of the GPL,
without warranty of any kind, from any PlumpOS mirror. Upon downloading,
unpack the archive
$ tar -xvzf plumpos-6.9-rc1.tar.gz                                           
and enter the new directory "plumpos-6.9-rc1/". Now you have several options
as to how you go about setting up PlumpOS.

First let's familiarize with the directory structure here. There should be 3

��*�rootdisk, which contains the layout of the iso to be created;
��*�scripts, which contains small programs used to help in the creation of
    the iso;
��*�final, which will contain the ISO generated by the whole process.

There should also be a file called install which you will run when you are
done configuring your system.

If you intend on using your own kernel with PlumpOS, there are several steps
you must follow in order for it to boot properly. First you must make a new
directory in the rootdisk/kernels/ directory that will be in the old and
often blamed DoS 8.3 character format and only contain letters and numbers
(and a single '.'). In that directory you should put a file named bzImage
which is your kernel and a file named modules.tgz which is a gzipped tarball
of your kernel's modules (with the relative path of lib/modules/ so it can be
extracted from the root dir). Optionally you can also provide the
and config file for your kernel. When this is done you may simply run the
install program and it will detect and install your kernel(s) for use with
the generated ISO.

Now, say you want to include a 3rd party add-on package. This is done very
simply: create a gzipped tarball containing all the files you want to include
in your package (relative to "/") and put these packages into the rootdisk/
packages/ directory. Then edit the file rootdisk/packages/list and add the
path relative to / on the ramdisk where the package can be located (in other
words for a package named "openssl.tar.gz", add the line "/cdrom/packages/
openssl.tar.gz" to the file rootdisk/packages/list). Optionally you can use a
line such as "cdrom:openssl.tar.gz" which will automatically search the
cdrom's packages directory for the package "openssl.tar.gz". In future
releases this will be useful for things like nfs and boot floppies, so for
now don't worry about it ;)

Chapter 7. Cluster Installation

7.1. Cluster Installations

This chapter does not deal with installing openMosix as such, it does however
deal with installing multiple machines with openMosix. Automated or semi
automated mass installs. 

7.2. DSH, Distributed Shell

At the time of this writing (May 2003) DSH's most current release is
available from More info
on the package can be found on
dsh.html The latest version available for download is 0.23.6 You will need
both libdshconfig-0.20.8.tar.gz and dsh-0.23.5.tar.gz Start with installing
make install                                                                 
Repeat the process for the dsh package.

Say we have a small cluster with a couple of nodes. To make life easier we
want type each command once but have it executed on each node. You then have
to create a file in $HOME/.dsh/group/clusterwname that lists the ip's of your
cluster. eg.
[root@inspon root]# cat .dsh/group/mosix                                                                                                                                                  
As an example we run ls on each of these machines We use -g to use the mosix
group (this way you can create subsets of a group with different
[root@inspon root]# dsh -r ssh -g mosix ls                           anaconda-ks.cfg                                                                                  install.log                                           install.log.syslog                                    openmosix-kernel-2.4.17-openmosix1.i686.rpm           openmosix-tools-0.2.0-1.i386.rpm                      anaconda-ks.cfg                                                                                                                          openmosix-kernel-2.4.17-openmosix1.i686.rpm          openmosix-tools-0.2.0-1.i386.rpm                     oscar-1.2.1rh72                                      oscar-1.2.1rh72.tar.gz                                       
Note that neither of the machines ask for a password. This is because we have
set up RSA authentication between the different accounts. If you want to run
commands with multiple parameters you will either have to put the command
between quotes.
[root@inspon root]# dsh -r ssh -g mosix "uname -a"                   Linux 2.4.17-openmosix1 #1     
Wed May 29 14:32:28 CEST 2002 i686 unknown                           Linux oscar0 2.4.17-openmosix1 #1 Wed May 29 14:32:28 CEST   
2002 i686 unknown                                                            
or use the -c -- option. Both give basically the same output.
[root@inspon root]# dsh -r ssh -g mosix -c -- uname -a               Linux oscar0 2.4.17-openmosix1 #1 Wed May 29 14:32:28 CEST   
2002 i686 unknown                                                    Linux 2.4.17-openmosix1 #1     
Wed May 29 14:32:28 CEST 2002 i686 unknown                                   

III. Administrating openMosix

Table of Contents
8. Administrating openMosix
    8.1. Basic Administration
    8.2. Configuration
    8.3. the userspace-tools
    8.4. Cluster Mask
9. Tuning Mosix
    9.1. Introduction
    9.2. Creating a "Master" node
    9.3. Optimizing Mosix
    9.4. Channel Bonding Made Easy
    9.5. Updatedb
    9.6. openMosix and FireWire
10. openMosixview
    10.1. Introduction
    10.2. openMosixview vs Mosixview
    10.3. Installation
    10.4. using openMosixview
    10.5. openMosixprocs
    10.6. openMosixcollector
    10.7. openMosixanalyzer
    10.8. openMosixmigmon
    10.9. openmosixview FAQ
    10.10. openMosixview + ssh:
11. Other openMosix related Programs
    11.1. Introduction
    11.2. openMosixView
    11.3. openMosixapplet
    11.4. wmonload
    11.5. openMosixWebView
12. Common Problems
    12.1. Introduction
    12.2. My processes won't migrate
    12.3. I don't see all my nodes
    12.4. I often get errors: No such process
    12.5. DFSA ? MFS ?
    12.6. Python Troubles
13. Hints and Tips
    13.1. Locked Processes
    13.2. Choosing your processes
    13.3. Java and openMosix
    13.4. openMosix and Hyperthreading
    13.5. openMosix and Firewalls
14. (stress)Testing your openMosix installation
    14.1. A small Test Script
    14.2. Perl Proggie by Charles Nadeau
    14.3. the openMosix stress-test

Chapter 8. Administrating openMosix

8.1. Basic Administration

openMosix provides the advantage of process migration to HPC-applications.
The administrator can configure and tune the openMosix-cluster by using the
openMosix-user-space-tools or the /proc/hpc interface which will be now
described in detail.

Up till openMosix version 2.4.16 the /proc interface was named /proc/mosix !
Until openMosix version 2.4.17 it was named /proc/hpc. 

8.2. Configuration

The values in the flat files in the /proc/hpc/admin directory presenting the
current configuration of the cluster. Also the administrator can write its
own values into these files to change the configuration during runtime, e.g.

Table 8-1. Changing /proc/hpc parameters
|echo 1 > /proc/hpc/admin/block|blocks the arrival of remote processes |
|echo 1 > /proc/hpc/admin/bring|bring all migrated processes home      |


Table 8-2. /proc/hpc/admin/
|(binary     |config        |the main configuration file (written by the    |
|files)      |              |setpe util)                                    |
|(flat files)|block         |allow/forbid arrival of remote processes       |
|�           |bring         |bring home all migrated processes              |
|�           |dfsalinks     |list of current symbolic dfsa-links            |
|�           |expel         |sending guest processes home                   |
|�           |gateways      |maximum number of gateways                     |
|�           |lstay         |local processes should stay                    |
|�           |mospe         |contains the openMosix node id                 |
|�           |nomfs         |disables/enables MFS                           |
|�           |overheads     |for tuning                                     |
|�           |quiet         |stop collecting load-load-balancing            |
|            |              |informations                                   |
|�           |decay-interval|interval for collecting informations about     |
|            |              |load-balancing                                 |
|�           |slow-decay    |default 975                                    |
|�           |fast-decay    |default 926                                    |
|�           |speed         |speed relative to PIII/1GHz)                   |
|�           |stay          |enables/disables automatic process migration   |

Table 8-3. Writing a 1 to the following files /proc/hpc/decay/
|clear |clears the decay statistics                   |
|cpujob|tells openMosix that the process is cpu-bound |
|iojob |tells openMosix that the process is io-bound  |
|slow  |tells openMosix to decay its statistics slow  |
|fast  |tells openMosix to decay its statistics fast  |

Table 8-4. Informations about the other nodes
|/proc/hpc/nodes/[openMosix_ID]/CPUs |how many CPU's the node has           |
|/proc/hpc/nodes/[openMosix_ID]/load |the openMosix load of this node       |
|/proc/hpc/nodes/[openMosix_ID]/mem  |available memory as openMosix believes|
|/proc/hpc/nodes/[openMosix_ID]/rmem |available memory as Linux believes    |
|/proc/hpc/nodes/[openMosix_ID]/speed|speed of the node relative to PIII/   |
|                                    |1GHz                                  |
|/proc/hpc/nodes/[openMosix_ID]/     |status of the node                    |
|status                              |                                      |
|/proc/hpc/nodes/[openMosix_ID]/tmem |available memory                      |
|/proc/hpc/nodes/[openMosix_ID]/util |utilization of the node               |

Table 8-5. Additional Informations about local processes
|/proc/[PID]/cantmove     |reason why a process cannot be migrated       |
|/proc/[PID]/goto         |to which node the process should migrate      |
|/proc/[PID]/lock         |if a process is locked to its home node       |
|/proc/[PID]/nmigs        |how many times the process migrated           |
|/proc/[PID]/where        |where the process is currently being computed |
|/proc/[PID]/migrate      |same as goto remote processes                 |
|/proc/hpc/remote/from    |the home node of the process                  |
|/proc/hpc/remote/identity|additional informations about the process     |
|/proc/hpc/remote/statm   |memory statistic of the process               |
|/proc/hpc/remote/stats   |cpu statistics of the process                 |

8.3. the userspace-tools

 These following tools are providing easy administration to openMosix
migrate -send a migrate request to a process                                 
                        migrate [PID] [openMosix_ID]                         
mon             -is a ncurses-based terminal monitor                                      
                 several informations about the current status are displayed in bar-charts
mosctl          -is the openMosix main configuration utility                                           
                        mosctl  [stay|nostay]                                                          
                        mosctl  whois   [openMosix_ID|IP-address|hostname]                             
                        mosctl  [getload|getspeed|status|isup|getmem|getfree|getutil]   [openMosix_ID] 
                        mosctl  setyard [Processor-Type|openMosix_ID||this]                            
                        mosctl  setspeed        interger-value                                         
                        mosctl  setdecay interval       [slow fast]                                    

Table 8-6. more detailed
|stay    |no automatic process migration                                    |
|nostay  |automatic process migration (default)                             |
|lstay   |local processes should stay                                       |
|nolstay |local processes could migrate                                     |
|block   |block arriving of guest processes                                 |
|noblock |allow arriving of guest processes                                 |
|quiet   |disable gathering of load-balancing informations                  |
|noquiet |enable gathering of load-balancing informations                   |
|nomfs   |disables MFS                                                      |
|mfs     |enables MFS                                                       |
|expel   |send away guest processes                                         |
|bring   |bring all migrated processes home                                 |
|gettune |shows the current overhead parameter                              |
|getyard |shows the current used Yardstick                                  |
|getdecay|shows the current decay parameter                                 |
|whois   |resolves openMosix-ID, ip-addresses and hostnames of the cluster  |
|getload |display the (openMosix-) load                                     |
|getspeed|shows the (openMosix-) speed                                      |
|status  |displays the current status and configuration                     |
|isup    |is a node up or down (openMosix kind of ping)                     |
|getmem  |shows logical free memory                                         |
|getfree |shows physical free mem                                           |
|getutil |display utilization                                               |
|setyard |sets a new Yardstick-value                                        |
|setspeed|sets a new (openMosix-) speed value                               |
|setdecay|sets a new decay-interval                                         |
mosrun          -run a special configured command on a chosen node                          
                        mosrun  [-h|openMosix_ID| list_of_openMosix_IDs] command [arguments]

The mosrun command can be executed with several more commandline options. To
ease this up there are several preconfigured run-scripts for executing jobs
with a special (openMosix) configuration.

Table 8-7. extra options for mosrun
|nomig    |runs a command which process(es) won't migrate                   |
|runhome  |executes a command locked to its home node                       |
|runon    |runs a command which will be directly migrated and locked to a   |
|         |node                                                             |
|cpujob   |tells the openMosix cluster that this is a cpu-bound process     |
|iojob    |tells the openMosix cluster that this is a io-bound process      |
|nodecay  |executes a command and tells the cluster not to refresh the      |
|         |load-balancing statistics                                        |
|slowdecay|executes a command with a slow decay interval for collecting     |
|         |load-balancing statistics                                        |
|fastdecay|executes a command with a fast decay interval for collecting     |
|         |load-balancing statistics                                        |
setpe           -manual node configuration utility                               
                        setpe   -w -f   [hpc_map]                                
                        setpe   -r [-f  [hpc_map]]                               
                        setpe   -off                                             
-w reads the openMosix configuration from a file (typically /etc/        
-r writes the current openMosix configuration to a file (typically /etc/ 
-off turns the current openMosix configuration off                               
tune            openMosix calibration and optimizations utility.             
                (for further informations review the tune-man page)          

Additional to the /proc interface and the commandline-openMosix utilities
(which are using the /proc interface) there is a patched "ps" and "top"
available (they are called "mps" and "mtop") which displays also the
openMosix-node ID on a column. This is useful for finding out where a
specific process is currently being computed.

This actually summarised the command line tools, but have a look at
openMosixview which is a GUI for the most common administration tasks, and
which ill be discussed in a future chapter.

8.4. Cluster Mask

(by Moshe Bar)

Several people have asked for a feature in openMosix which allows to specifiy
to which nodes a given process and it's children can migrate and to which
nodes it cannot.

Simone Ettore has just committed a new patch to the CVS which allows you to
do just that.

Here is how it works:

��*�/proc/[pid]/migfilter enable/disable the capability of filter migration.
��*�/proc/[pid]/mignodes is a bit-list of nodes. The bit position of a node
    is calculated as 2^(PE-1). PE is node number.
��*�/proc/[pid]/migpolicy is the policy of the filtering: 0=DENY: the process
    can migrate in all nodes except when the relative bit on mignodes is 1 1=
    ALLOW: the process can migrate in all nodes where the relative bit on
    mignodes is 1

 We are shortly going to release also a simple user-land tool to set the node
mask, but I would like you guys to give it a try asap before we release it as
openMosix 2.4.20-3.

Chapter 9. Tuning Mosix

9.1. Introduction

Some of the parts below are still from the old Mosix Howto, as time passes
these parts will get replaced by relevant openMosix parts, however some
things are still the same , but your mileage may vary.

9.2. Creating a "Master" node

Although openMosix architcture does not require a master node as such, you
might want to have a head node from where you launch processes, this might be
a multihomed node from where users log in to your cluster. You want to
configure your machine to make processes migrate away

You have to trick the node in thinking it is the slowest node around and it'd
better migrate all it's processes to the faster nodes.

You will have to make it "slow" with :
mosctl setspeed [n]                                                          
where n should be much lower than the speed of the other nodes Processes will
move/migrate away fast. You can get the speed of a node with :
mosctl getspeed                                                              

9.3. Optimizing Mosix

Editorial Comment: To be checked with openMosix versions 

Login a normal terminal as root. Type
       setpe -r                                                              
which, if everything went right, will give you a listing of your /etc/ If things did not go right, try
        setpe -w -f /etc/                                           
to set up your node. Then, type
       cat /proc/$$/lock                                                     
to see if your child processes are locked in your mode (1) or can migrate
(0). If for some reason you find your processes are locked, you can change
this with
        echo 0 > /proc/$$/lock                                               
until you fix the problem. Repeat the whole configuration scheme for a second
computer. The programs tune_kernel and prep_tune that Mosix uses to calibrate
the individual nodes do not work with the SuSE distribution. However, you can
fake it. First, bring the computer you want to tune and another computer with
Mosix installed down to single user mode by typing
        init 1                                                               
as root. All other computers on the network should be shutdown if possible.
On both machines, run the following commands:
        /etc/init.d/network start                                            
        /etc/init.d/mosix start                                              
        echo 1 > /proc/mosix/admin/quiet                                     
This fakes prep_tune and the first parts of tune_kernel. Note that if you
have a laptop with a pcmcia network card, you will have to run
        /etc/init.d/pcmcia start                                             
instead of "/etc/init.d/network start". On the computer you want to tune, run
tune_kernel and follow instructions. Depending on your machines, this can
take a while - if you have a dog, this might be the time to go on that long,
long walk you've always promised him. tune_kernel will create a program
called "pg" in /root for testing reasons. Ignore it. After tuning is over,
copy the contents of /tmp/overheads to the file /etc/overheads (and/or
recompile the kernel). Repeat the tuning procedure for each computer. Reboot,
enjoy Mosix, and don't forget to brag to your friends about your new cluster.

9.4. Channel Bonding Made Easy

Contributed by Evan Hisey

Channel bonding is actually horrible easy. This may explain the lack of
documentation on this subject A bonded network appears as a normal network to
the applications. All machines on a subnet must be bonded the same way.
Bonded and non-bonded machine really don't talk well to each other.

 Channel bonding needs at least two physical sub-nets but can have more
(Currently I have a tri-bonded cluster). To enable bonding you need to either
compile in to the kernel or as a module (bonding.o) the Channel Bonding
kernel code, as of 2.4.x is it a standard option of the kernel. The NIC's are
setup as normal with except that you only us 'ifconfig' to initialize the
first card of the bond. 'ifenslave' is used to initialize the remaining cards
in the bonded connection. 'ifenslave' can be locate in the linux/
Documentation/network/ directory. It will need to be compiled as it is a .c
file. The basic format for use is
ifenslave <master> <slave1> <slave2> ...                                     
Channel bonded networks can connect to standard networks via a router or
bridge that supports channel bonding( I just use an extra NIC and
port-forwarding in the head node).

9.5. Updatedb

Updatedb in combination with mfs can cause some issues, you might want to add
/mfs to the PRUNEFPATHS or mfs to the PRUNEFS in your /etc/updatedb.conf to
disable updatedb from indexing this mountpoints. 

9.6. openMosix and FireWire

openMosix does gain performance by using another type of network device, as
described within the paper about openMosix and FireWire

Chapter 10. openMosixview

10.1. Introduction

  openMosixview is the next version and a complete rewrite of Mosixview. It
is a cluster-management GUI for openMosix-cluster and everybody is invited to
download and use it (at your own risk and responsibility). The
openMosixview-suite contains 5 useful applications for monitoring and
administrating openMosix-cluster.


openMosixview the main monitoring+administration application                
openMosixprocs a process-box for managing processes                         
openMosixcollector collecting daemon which logs cluster+node informations   
openMosixanalyzer for analyzing the data collected by the openMosixcollector
openMosixhistory a process-history for your cluster                         


  All parts are accessible from the main application window. The most common
openMosix-commands are executable by a few mouse-clicks. An advanced
execution dialog helps to start applications on the cluster.
"Priority-sliders" for each node simplifying the manual and automatic
load-balancing. openMosixview is now adapted to the openMosix-auto-discovery
and gets all configuration-values from the openMosix /proc-interface.  

10.2. openMosixview vs Mosixview

openMosixview is fully designed for openMosix cluster only. The
Mosixview-website (and all mirrors) will stay as they are but all further
developing will continue with openMosixview located at the new domain

 If you have: questions, features wanted, problems during installation,
comments, exchange of experiences etc. feel free to mail me, Matt Rechenburg
or subscribe to the openMosix/Mosixview-mailing-list and mail to the

 changes: (to Mosixview 1.1) openMosixview is a complete rewrite "from the
scratch" of Mosixview! It has the same functionalities but there are
fundamental changes in ALL parts of the openMosixview source-code. It is
tested with a constantly changing cluster topography (required for the
openMosix auto-discovery) All "buggy" parts are removed or rewritten and it
(should ;) run much more stable now.  

adapted to the openMosix-auto-discovery                       
not using /etc/ or any cluster-map file anymore      
removed the (buggy) map-file parser                           
rewrote all parts/functions/methods to a cleaner c++ interface
fixed some smaller bugs in the display                        
replaced MosixMem+Load with the openMosixanalyzer             
... many more changes                                         

10.3. Installation


QT library                                                                   
root rights !                                                                
rlogin and rsh (or ssh) to all cluster-nodes without password the openMosix  
userland-tools mosctl, migrate, runon, iojob, cpujob ... (download them from 
the website)                                               

On a RH 8.0 you will need at least the following rpm's qt-3.0.5-17,
libmng-1.0.4, XFree86-Mesa-libGLU-4.2.0, glut-3.7 etc ... 

Documentation about openMosixview There is a full HTML-documentation about
openMosixview included in every package. You find the startpage of the
documentation in your openMosixview installation directory: openmosixview/

 The RPM-packages have their installation directories in: /usr/local/

10.3.1. Installation of the RPM-distribution

 Download the latest version of openMosixview rpm-package. Then just execute
rpm -i openmosixview-1.4.rpm                                                 
This will install all binaries in /usr/bin To uninstall:
rpm -e openmosixview                                                         

10.3.2. Installation of the source-distribution

 Download the latest version of openMosixview and unzip+untar the sources and
copy the tarball to e.g. /usr/local/.
gunzip openmosixview-1.4.tar.gz                                              
tar -xvf openmosixview-1.4.tar                                               

10.3.3. Automatic setup-script

 Just cd to the openmosixview-directory and execute
./setup [your_qt_2.3.x_installation_directory]                               

10.3.4. Manual compiling

Set the QTDIR-Variable to your actual QT-Distribution, e.g.
export QTDIR=/usr/lib/qt-2.3.0 (for bash)                                    
setenv QTDIR /usr/lib/qt-2.3.0 (for csh)                                     

10.3.5. Hints

(from the testers of openMosixview/Mosixview who compiled it on different
linux-distributions, thanks again) Create the link /usr/lib/qt pointing to
your QT-2.3.x installation e.g. if QT-2.3.x is installed in /usr/local/
ln -s /usr/local/qt-2.3.0 /usr/lib/qt                                        
Then you have to set the QTDIR environment variable to
export QTDIR=/usr/lib/qt (for bash)                                          
setenv QTDIR /usr/lib/qt (for csh)                                           
After that the rest should work fine:
then do the same in the subdirectory openmosixcollector, openmosixanalyzer,
openmosixhistory and openmosixviewprocs. Copy all binaries to /usr/bin
cp openmosixview/openmosixview /usr/bin                                      
cp openmosixviewproc/openmosixviewprocs/mosixviewprocs /usr/bin              
cp openmosixcollector/openmosixcollector/openmosixcollector /usr/bin         
cp openmosixanalyzer/openmosixanalyzer/openmosixanalyzer /usr/bin            
cp openmosixhistory/openmosixhistory/openmosixhistory /usr/bin               
And the openmosixcollector init-script to your init-directory e.g.
cp openmosixcollector/openmosixcollector.init /etc/init.d/openmosixcollector      
cp openmosixcollector/openmosixcollector.init /etc/rc.d/init.d/openmosixcollector 
Now copy the openmosixprocs binary on each of your cluster-nodes to /usr/bin/
rcp openmosixprocs/openmosixprocs your_node:/usr/bin/openmosixprocs          
You can now execute mosixview

10.4. using openMosixview

10.4.1. main application

 Here is a picture of the main application-window. The functionality is
explained in the following.


 openMosixview displays a row with a lamp, a button, a slider, a lcd-number,
two progress-bars and some labels for each cluster-member. The lights at the
left are displaying the openMosix-Id and the status of the cluster-node. Red
if down, green for available.

 If you click on a button displaying the ip-address of one node a
configuration-dialog will pop up. It shows buttons to execute the most common
used "mosctl"-commands. (described later in this HOWTO) With the
"speed-sliders" you can set the openMosix-speed for each host. The current
speed is displayed by the lcd-number.

 You can influence the load-balancing of the whole cluster by changing these
values. Processes in a openMosix-Cluster are migrating easier to a node with
more openMosix-speed than to nodes with less speed. Sure it is not the
physically speed you can set but it is the speed openMosix "thinks" a node
has. e.g. a cpu-intensive job on a cluster-node which speed is set to the
lowest value of the whole cluster will search for a better processor for
running on and migrate away easily.

 The progress bars in the middle gives an overview of the load on each
cluster-member. It displays in percent so it does not represent exactly the
load written to the file /proc/hpc/nodes/x/load (by openMosix), but it should
give an overview.

 The next progressbar is for the used memory the nodes. It shows the
currently used memory in percent from the available memory on the hosts (the
label to the right displays the available mem). How many CPUs your cluster
have is written in the box to the right. The first line of the main windows
contains a configuration button for "all-nodes". You can configure all nodes
in your cluster similar by this option.

 How good the load-balancing works is displayed by the progressbar in the top
left. 100% is very good and means that all nodes nearly have the same load.

 Use the collector- and analyzer-menu to manage the openMosixcollector and
open the openMosixanalyzer. This two parts of the openMosixview-application
suite are useful for getting an overview of your cluster during a longer

10.4.2. the configuration-window

 This dialog will pop up if an "cluster-node"-button is clicked.


 The openMosix-configuration of each host can be changed easily now. All
commands will be executed per "rsh" or "ssh" on the remote hosts (even on the
local node) so "root" has to "rsh" (or "ssh") to each host in the cluster
without prompting for a password (it is well described in a Beowulf
documentation or on the HOWTO on this page how to configure it).

  The commands are:
automigration on/off                                                         
quiet yes/no                                                                 
bring/lstay yes/no                                                           
exspel yes/no                                                                
openMosix start/stop                                                         
If openMosixprocs is properly installed on the remote cluster-nodes click the
"remote proc-box"-button to open openMosixprocs (proc-box) from remote. xhost
+hostname will be set and the display will point to your localhost. The
client is executed on the remote also per "rsh" or "ssh". (the binary
openmosixprocs must be copied to e.g. /usr/bin on each host of the cluster)
openMosixprocs is a process-box for managing your programs. It is useful to
manage programs started and running local on the remote nodes and is
described later in this HOWTO.

 If you are logged on your cluster from a remote workstation insert your
local hostname in the edit-box below the "remote proc-box". Then
openMosixprocs will be displayed on your workstation and not on the
cluster-member you are logged on. (maybe you have to set "xhost +clusternode"
on your workstation). There is a history in the combo-box so you have to
write the hostname only once.

10.4.3. advanced-execution

If you want to start jobs on your cluster the "advanced execution"-dialog may
help you.


 Choose a program to start with the "run-prog" button (file-open-icon) and
you can specify how and where the job is started by this execution-dialog.
There are several options to explain.

10.4.4. the command-line

 You can specify additional commandline-arguments in the lineedit-widget on
top of the window.

Table 10-1. how to start
|-no migration|start a local job which won't migrate                        |
|-run home    |start a local job                                            |
|-run on      |start a job on the node you can choose with the              |
|             |"host-chooser"                                               |
|-cpu job     |start a computation intensive job on a node (host-chooser)   |
|-io job      |start a io intensive job on a node (host-chooser)            |
|-no decay    |start a job with no decay (host-chooser)                     |
|-slow decay  |start a job with slow decay (host-chooser)                   |
|-fast decay  |start a job with fast decay (host-chooser)                   |
|-parallel    |start a job parallel on some or all node (special            |
|             |host-chooser)                                                |

10.4.5. the host-chooser

For all jobs you start non-local simple choose a host with the dial-widget.
The openMosix-id of the node is also displayed by a lcd-number. Then click
execute to start the job.

10.4.6. the parallel host-chooser

You can set the first and last node with 2 spinboxes. Then the command will
be executed an all nodes from the first node to the last node. You can also
inverse this option.

10.5. openMosixprocs

10.5.1. intro

 This process-box is really useful for managing the processes running on your

You should install it on every cluster-node!

 The processlist gives an overview what is running where. The second column
displays the openMosix-node ID of each process. 0 means local, all other
values are remote nodes. Migrated processes are marked with a green icon and
non movable processes have a lock.

 By double-clicking a process from the list the migrator-window will pop-up
for managing e.g. migrating the process. There are also options to migrate
the remote processes away, send SIGSTOP and SIGCONT to it or to "renice" it.

 If you click on the "manage procs from remote" button a new window will come
up (the remote-procs windows) displaying the process currently migrated to
this host.

10.5.2. the migrator-window

This dialog will pop up if process from the process box is clicked.  


 The openMosixview-migrator window displays all nodes in your
openMosix-cluster. This window is for managing one process (with additional
status-information). By double-clicking on an host from the list the process
will migrate to this host. After a short moment the process-icon for the
managed process will be green, which means it is running remote.

 The "home"-button sends the process to its home node. With the "best"-button
the process is send to the best available node in your cluster. This
migration is influenced by the load, speed, CPU's and what openMosix "thinks"
of each node. It maybe will migrate to the host with the most CPU's and/or
the best speed. With the "kill"-button you can kill the process immediately.

 To pause a program just click the "SIGSTOP"-button and to continue the
"SIGCONT"-button. With the renice-slider below you can renice the current
managed process (-20 means very fast, 0 normal and 20 very slow)

10.5.3. managing processes from remote

  This dialog will pop up if the "manage procs from remote"-button beneath
the process-box is clicked


 The TabView displays processes that are migrated to the local host. The
procs are coming from other nodes in your cluster and currently computed on
the host openMosixview is started on. Similar to the two buttons in the
migrator-window the process is send home by the "goto home node"-button and
send to the best available node by the "goto best node"-button.  

10.6. openMosixcollector

The openMosixcollector is a daemon which should/could be started on one
cluster-member. It logs the openMosix-load of each node to the directory /tmp
/openmosixcollector/* These history log-files analyzed by the
openMosixanalyzer (as described later) gives an nonstop overview of the load,
memory and processes in your cluster. There is one main log-file called /tmp/
openmosixcollector/cluster Additional to this there are additional files in
this directory to which the data is written.

 At startup the openMosixcollector writes its PID (process id) to /var/run/

 The openMosixcollector-daemon restarts every 12 hours and saves the current
history to /tmp/openmosixcollector[date]/* These backups are done
automatically but you can also trigger this manual.

 There is an option to write a checkpoint to the history. These checkpoints
are graphically marked as a blue vertical line if you analyze the history
log-files with the openMosixanalyzer. For example you can set a checkpoint
when you start a job on your cluster and another one at the end..

 Here is the explanation of the possible commandline-arguments:
openmosixcollector -d      //starts the collector as a daemon                
openmosixcollector -k      //stops the collector                             
openmosixcollector -n      //writes a checkpoint to the history              
openmosixcollector -r      //saves the current history and starts a new one  
openmosixcollector         //print out a short help                          

 You can start this daemon with its init-script in /etc/init.d or /etc/rc.d/
init.d. You just have to create a symbolic link to one of the runlevels for
automatic startup.

 How to analyze the created logfiles is described in the

10.7. openMosixanalyzer

10.7.1. the load-overview

  This picture shows the graphical Load-overview in the openMosixanalyzer
(Click to enlarge)


 With the openMosixanalyzer you can have a non-stop openMosix-history of your
cluster. The history log-files created by openMosixcollector are displayed in
a graphically way so that you have a long-time overview what happened and
happens on your cluster. The openMosixanalyzer can analyze the current
"online" logfiles but you can also open older backups of your
openMosixcollector history logs by the filemenu. The logfiles are placed in /
tmp/openmosixcollector/* (the backups in /tmp/openmosixcollector[date]/*) and
you have to open only the main history file "cluster" to take a look at older
load-informations. (the [date] in the backup directories for the log-files is
the date the history is saved) The start time is displayed on the top and you
have a full-day view in the openMosixanalyzer (12 h).

 If you are using the openMosixanalyzer for looking at "online"-logfiles
(current history) you can enable the "refresh"-checkbox and the view will

 The load-lines are normally black. If the load increases to >75 the lines
are drawn red. These values are openMosix--informations. The
openMosixanalyzer gets these informations from the files /proc/hpc/nodes/
[openMosix ID]/*

 The Find-out-button of each nodes calculates several useful statistic
values. Clicking it will open a small new window in which you get the average
load- and mem values and some more statically and dynamic informations about
the specific node or the whole cluster.

10.7.2. statistical informations about a cluster-node


  If there are checkpoints written to the load-history by the
openMosixcollector they are displayed as a vertical blue line. You now can
compare the load values at a certain moment much easier.

10.7.3. the memory-overview


This picture shows the graphical Memory-overview in the openMosixanalyzer

 With Memory-overview in the openMosixanalyzer you can have a non-stop memory
history similar to the Load-overview. The history log-files created by
openMosixcollector are displayed in a graphically way so that you have a
long-time overview what happened and happens on your cluster. It analyze the
current "online" logfiles but you can also open older backups of your
openMosixcollector history logs by the filemenu.

 The displayed values are openMosix-informations. The openMosixanalyzer gets
these informations from the files

  If there are checkpoints written to the memory-history by the
openMosixcollector they are displayed as a vertical blue line.

10.7.4. openMosixhistory


 displays the processlist from the past 

openMosixhistory gives a detailed overview which process was running on which
node. The openMosixcollector saves the processlist from the host the
collector was started on and you can browse this log-data with
openMosixhistory. You can easy change the browsing time in openMosixhistory
by the time-slider.

 openMosixhistory can analyze the current "online" logfiles but you can also
open older backups of your openMosixcollector history logs by the filemenu.

  The logfiles are placed in /tmp/openmosixcollector/* (the backups in /tmp/
openmosixcollector[date]/*) and you have to open only the main history file
"cluster" to take a look at older load-informations. (the [date] in the
backup directories for the log-files is the date the history is saved) The
start time is displayed on the top/left and you have a 12 hour view in

10.8. openMosixmigmon

10.8.1. General


The openMosixmigmon is a monitor for migrations in your openMosix-cluster. It
displays all your nodes as little penguins sitting in a circle.

-> nodes-circle.

The main penguin is the node on which openMosixmigmon runs and around this
node it shows its processes also in a circle of small black squares.

-> main process-circle

 If a process migrates to one of the nodes the node gets an own
process-circle and the process moved from the main process-circle to the
remote process-circle. Then the process is marked green and draws a line from
its origin to its remote location to visualize the migration.

10.8.2. Tooltips:

If you hold your mouse above a process it will show you its PID and
commandline in a small tooltip-window.

10.8.3. Drag'n Drop!

 The openMosixmigmon is fully Drag'n Drop enabled. You can grab (drag) any
process and drop them to any of your nodes (those penguins) and the process
will move there. If you double-click a process on a remote node it will be
send home immediately.

10.9. openmosixview FAQ

10.9.1. I cannot compile openMosixview on my system? 
10.9.2. Can I use openMosixview with SSH?
10.9.3.  I started openMosixview but only the splash-screen appears. What is
10.9.4.  The openMosixviewprocs/mosixview_client is not working for me!
10.9.5.   Why are the buttons in the openMosixview-configuration dialog not

10.9.1. I cannot compile openMosixview on my system? 

At first QT >= 2.3.x is required. The QTDIR -environment variable has to be
set to your QT-installation directories like it is well described in the
INSTALL- file. In versions < 0.6 you can do a "make clean" and delete the two
files: /openmosixview/Makefile /openmosixview/config.cache and try to compile
again because i alway left the binary- and object-files in older versions. If
you have any other problems post them to the openMosixview-mailinglist (or
directly to me).  

10.9.2. Can I use openMosixview with SSH?

Yes, until version 0.7 there is a built-in SSH-support. You have to be able
to ssh to each node in your cluster without password (just like the same with
using RSH this is required)

10.9.3. I started openMosixview but only the splash-screen appears. What is

Do not fork openMosixview in the background with & (e.g. openMosixview &).
Maybe you cannot rsh/ssh (depends on what you want to use) as user root
without password to each node? Try "rsh hostname" as root. You should not
been promped for a password but soon get a login shell. (If you use SSH try
"ssh hostname" as root.) You have to be root on the cluster because that is
the only way the administrative commands executed by openMosixview requires
root-privileges. openMosixview uses "rsh" as the default! If you only have
"ssh" installed on your cluster edit (or create) the file /root
/.openMosixview and put "1111" in it. This is the main-configuration file for
openMosixview and the last "1" stands for "use ssh instead of rsh". This will
cause openMosixview to use "ssh" even for the first start.  

10.9.4. The openMosixviewprocs/mosixview_client is not working for me!

The openMosixview-client is executed per rsh (or ssh which you can configer
whith a checkbox) on the remote host. It has to be installed in /usr/bin/ on
each node. If you use RSH try: "xhost +hostname" "rsh hostname /usr/bin/
openMosixview_client -display your_local_host_name:0.0" or if you use SSH
try: "xhost +hostname" "ssh hostname /usr/bin/openMosixview_client -display
your_local_host_name:0.0" If this works it will work in openMosixview too.
openMosixview crashes with "segmentation fault"! Maybe you still use an old
version of openMosixview/Mosixview ? in the (which is
completly removed in openMosixview !!) (the versions openMosixview 1.2 and
Mosixview > 1.0 are stable)

10.9.5. Why are the buttons in the openMosixview-configuration dialog not

(automigration on/off, blocking on/off......) I want them to be preselected
too. The problem is to get the information of node. You have to login to each
cluster-node because these information are not cluster-wide (to my mind). The
status of each node is stored in the /proc/hpc/admin directory of each node.
Everybody who knows a good way to get these information easy is invited to
mail me.  

10.10. openMosixview + ssh:

(this HowTo is for SSH2) You can read the reasons why you should use SSH
instead of RSH everyday on the newspaper when another script-kiddy hacked
into an insecure system/network. So SSH is a good decision at all.
freedom x security = constant    (from a security newsgroup)                 
That is why it is a bit tricky to configure SSH. SSH is secure even if you
use it to login without being prompted for a password. Here is a (one) way to
configure it.

At first a running secure-shell daemon on the remote site is required. If it
is not already installed install it! (rpm -i
[sshd_rpm_packeage_from_your_linux_distribution_cd]) If it is not already
running start it with:
/etc/init.d/ssh start                                                        
Now you have to generate a keypair for SSH on your local computer whith
You will be prompt for a passphrase for that keypair. The passphrase normally
is longer than a password and may be a whole sentence. The keypair is
encrypted with that passphrase and saved in
/root/.ssh/identity    //your private key                                    
/root/.ssh/     //your public key                                
Do NOT give your private-key to anybody!!! Now copy the whole content of /
root/.ssh/ (your public-key which should be one long line) into /
root/.ssh/authorized_keys on the remote host. (also copy the content of /root
/.ssh/ to your local /root/.ssh/authorized_keys like you did it
with the remote-node because openMosixview needed password-less login to the
local-node too!)

 If you ssh to this remote host now you will be prompted for the passphrase
of your public-key. Giving the right passphrase should give you a login.

 What is the advantage right now??? The passphrase is normally a lot longer
than a password!

 The advantage you can get using the ssh-agent. It manages the passphrase
during ssh login.
The ssh-agent is started now and gives you two environment-variables you
should set (if not set already). Type:
echo $SSH_AUTH_SOCK                                                          
echo $SSH_AGENT_PID                                                          
to see if they are exported to your shell right now. If not just cut and
paste from your terminal. e.g. for the bash-shell:
export SSH_AUTH_SOCK                                                         
export SSH_AGENT_PID                                                         
example for the csh-shell:
setenv SSH_AUTH_SOCK /tmp/ssh-XXYqbMRe/agent.1065                            
setenv SSH_AGENT_PID 1066                                                    
With these variables the remote-sshd-daemon can connect your local ssh-agent
by using the socket-file in /tmp (in this example /tmp/ssh-XXYqbMRe/
agent.1065). The ssh-agent can now give the passphrase to the remote host by
using this socket (it is of course an encrypted transfer)!

 You just have to add your public-key to the ssh-agent with the ssh-add
Now you should be able to login using ssh to the remote host without being
prompted for a passwod!

 You could (should) add the ssh-agent and ssh-add commands in your
login-profile e.g.
eval `ssh-agent`                                                             
Now it is started when you login on your local workstation. You have done it!
I wish you secure logins now.

 openMosixview There is a menu-entry which toggles using rsh/ssh with
openMosixview. Just enable this and you can use openMosixview even in
insecure network-environments. You should also save this configuration (the
possibility for saveing the current config in openMosixview was added in the
0.7 version) because it gets initial data from the slave using rsh or ssh
(just like you configured).  

 If you choose a service wich is not installed properly openMosixview will
not work! (e.g. if you cannot rsh to a slave without being prompted for a
password you cannot use openMosixview with RSH; if you cannot ssh to a slave
without being prompted for a password you cannot use openMosixview with SSH)

Chapter 11. Other openMosix related Programs

11.1. Introduction

There are a couple of different applications available to monitor and admin
openMosix, we give a short overview of them in this chapter, we won't really
go in detail. 

11.2. openMosixView

openMosixview is the most used and the best known applet for openMosix
administration, you can read more about it in the openMosix adminstration

11.3. openMosixapplet

The openMosixApplet lets you watch the realtime load of your openMosix
cluster. It consists of a local daemon which listens for connections by
applets. The applet uses chart2D to provide a good-lookin' feeling.

11.4. wmonload

wmomload is a simple, but handy and small dockapp for overviewing the load of
cluster nodes in a small openMosix-based cluster.

11.5. openMosixWebView

openMosixWebView - Produces web charts for monitoring an openMosix cluster.
openMosixWebView is a PHP script for monitoring an openMosix cluster via the
WEB. It uses openMosixview's openMosixCollector logs. Download now the last
release  openmosixwebview-0.2.12.tar.gz (16 Feb 2003)

See openMosixWebView screenshots and running :-) Released under the GNU
General Public License (GPL). See README and FAQ files. 

Chapter 12. Common Problems

12.1. Introduction

Although most of the issues in this chapter could be a part of the FAQ. There
where the FAQ will give a short "how to solve" answer, we have taken a closer
look at them and explained why they are problems and how to solve them.

12.2. My processes won't migrate

Help process XYZ doesn't migrate. Moshe Bar explains below why some processes
migrate and why some don't. But before that you can always look in /proc/$pid
/, there often is a cantmove file which will tell you why a certain process
can't migrate.

Processes can also be locked. You can check if a process is locked with:
cat /proc/$PID/lock                                                          
where $PID is the processid of the process in question. 

Now listen to what Moshe himself has to say about this topic. 

Often people have the same kernel but on a different distribution, say a
mixed environment of RedHat and Debian ,rc scripts from different distros
tend to start openmosix differently. Some implementations completely modify /
etc/inittab to start all daemons (and their children) with
mosrun -h                                                                    
. So that they won't migrate. Therefore all these processes have a 1 in /proc
/pid/lock when you start. You can force them to migrate by writing a 0 to
this file .

  Ok, this simple program should always migrate if launched more times than
number of local CPUs. So for a 2-way SMP system, starting this program 3
times will start migration if the other nodes in the cluster have at least
the same speed like the local ones:
int main() {                                                                 
    unsigned int i;                                                          
    while (1) {                                                              
    return 0;                                                                
On a Pentium 800Mhz CPU it takes quite a while to overflow. 

  This sample program with content like this will never migrate:
#include <sys/types.h>                                                       
#include <sys/ipc.h>                                                         
#include <sys/shm.h>                                                         
key_t key; /* key to be passed to shmget() */                                
int shmflg; /* shmflg to be passed to shmget() */                            
int shmid; /* return value from shmget() */                                  
int size; /* size to be passed to shmget() */                                
key = ...                                                                    
size = ...                                                                   
shmflg) = ...                                                                
if ((shmid = shmget (key, size, shmflg)) == -1) {                            
   perror("shmget: shmget failed"); exit(1); } else {                        
   (void) fprintf(stderr, "shmget: shmget returned %d\n", shmid);            

 Program using pipes like this do migrate nicely:
int pdes[2];                                                                 
if ( fork() == 0 )                                                           
  { /* child */                                                              
                                 close(pdes[1]); /* not required */          
                                 read( pdes[0]); /* read from parent */      
                 { close(pdes[0]); /* not required */                        
                                 write( pdes[1]); /* write to child */       
MODIFIED Programs using pthreads since version 2.4.17 don't migrate, however
they don't segfault anymore.
// Very simple program demonstrating the use of threads.                     
// Command-line argument is P (number of threads).                           
// Each thread writes "hello" message to standard output, with               
//   no attempt to synchronize.  Output will likely be garbled.              
#include <iostream>                                                          
#include <cstdlib>              // has exit(), etc.                          
#include <unistd.h>             // has usleep()                              
#include <pthread.h>            // has pthread_ routines                     
// declaration for function to be executed by each thread                    
void * printHello(void * threadArg);                                         
// ---- Main program -------------------------------------------------       
int main(int argc, char* argv[]) {                                           
  if (argc < 2) {                                                            
    cerr << "Usage:  " << argv[0] << " numThreads\n";                        
  int P = atoi(argv[1]);                                                     
  // Set up IDs for threads (need a separate variable for each               
  //   since they're shared among threads).                                  
  int * threadIDs = new int[P];                                              
  for (int i = 0; i < P; ++i)                                                
    threadIDs[i] = i;                                                        
  // Start P new threads, each with different ID.                            
  pthread_t * threads = new pthread_t[P];                                    
  for (int i = 0; i < P; ++i)                                                
    pthread_create(&threads[i], NULL, printHello,                            
                   (void *) &threadIDs[i]);                                  
  // Wait for all threads to complete.                                       
  for (int i = 0; i < P; ++i)                                                
    pthread_join(threads[i], NULL);                                          
  // Clean up and exit.                                                      
  delete [] threadIDs;                                                       
  delete [] threads;                                                         
  cout << "That's all, folks!\n";                                            
  return EXIT_SUCCESS;                                                       
// ---- Code to be executed by each thread ---------------------------       
// pre:  *threadArg is an integer "thread ID".                               
// post:  "hello" message printed to standard output.                        
//        return value is null pointer.                                      
void * printHello(void * threadArg) {                                        
  int * myID = (int *) threadArg;                                            
  cout << "hello, world, ";                                                  
  // pointless pause, included to make the effects of                        
  //   synchronization (or lack thereof) more obvious                        
  cout << "from thread " << *myID << endl;                                   
  pthread_exit((void* ) NULL);                                               
Programs using all kinds of file descriptors, including sockets do migrate
(sockets are not migrated with the process however, files are migrated if
using oMFS/DFSA)

 (all above code is by Moshe as Moshe Bar or by Moshe as CTO of Qlusters,

Please also refer to the man pages of openMosix , they also give an adequate
explanation why processes don't migrate. 

If for some reason your processes stay locked while they shouldn't. You can
try to allow locked processes to migrate by simply putting
# tell shells to allow subprocs to migrate to other nodes                    
echo 0 > /proc/self/lock                                                     
into "/etc/profile" Warning : this fix will allow all process to migrate not
just the ones you want. To only allow specific process to migrate use 'mosrun
-l' to unlock only the desired process.  

12.3. I don't see all my nodes

 First of all , are you using the same kernel version on each machine ? The
'same-kernel' refers to the version. You can build different kernel images of
the same source version to meet the hardware/software needs of a given node.
However you wil need toe make sure that when you install openMosix on your
cluster, all your machines should have the openmosix-x.x.x-y kernel
installed, in contrast to having one machine running openmosix-x.x.z-x,
another running openmosix-x.x.x-y, another running openmosix x.x.x-z, and so
on and so forth  

 When you run mosmon, press t to see the total of machines running. Does it
warn you that mosix is not running?

 If yes, then make sure your machine's ip is included in /etc/
(don't use - if your machine's ip is such, then you probably have
problems with your dhcp server/nameserver). If it does not tell you that
mosix is not running, see what machines show up. Do you see only your

 If yes, then your machine is most likely running a firewall and is not
letting openmosix through.

 If not, then the problem is most likely with the machine that doesn't show
up. Also: Do you have two nic cards on a node? then you have to edit the /etc
/hosts file to have a line that has the following format
non-cluster_ip  cluster-hostname.cluster-domain cluster-hostname             
You might also need to set up a routing table, which is a whole different

Maybe you used different kernel-parameters on each machine? Especially if you
use the 'Support clusters with a complex network topology' option you should
take care that you use the same value for the also appearing option 'Maximum
network-topology complexity support' on each machine.

12.4. I often get errors: No such process

I often get the error
bash: child setpgid (4061 to 4061): No such process                          
what does this mean ?  

The above line meas that the shell you were using has acutallly migrated to
another node ? This printout from bash is caused by a bug in old version of
openmosix, but a fix has been commited. (Muli Ben-Yehuda 

12.5. DFSA ? MFS ?

People often get confused about what exactly MFS and DFSA are. As discussed
before in the howto MFS is the feature of openMosix that enables you access
to remote filesystems as if those filesystems were locally mounted. They are
mostly mounted on /mfs . A common misunderstanding is that you need MFS in
order to have openMosix working, this is not true, however it can make things

With DFSA enabled, system calls will be executed on the remote node withouth
migrating the process back to it's home node. This behaviour (direct
filesystem access) causes processes migratiing to the data and not the other
way around (which is common). If DFSA is not enabled MfS is "just" a
non-caching network-filesystem.

  Very generally speaking, if you don't have DFSA turned on, each and every I
/O will go to the home node for execution. With DFSA turned on, if the file
happens to be residing on the node where the process finds itself then the I/
O will happen locally. 

 A very common error is that people mix kernels with DFSA enabled and
disabled. So one has to have a way to find out wether DFSA is actually
enabled. This information can be obtained by typing
cat /proc/hpc/admin/version                                                  

12.6. Python Troubles

Some people have reported problems with Python, closer research showed that
these problems were not with openMosix but rather with glibc issues, however
it seemed that issues manifested themselves especially in openMosix.

One user solved the problem by removig /lib/i686/lib* on his machine and let
the applications link dynamically against /lib/libpthread (and other) However
bugfixes in newer glibc versions combined with more recent openMosix version
seem to have solved these problems.  

Chapter 13. Hints and Tips

13.1. Locked Processes

If for some reason you find your processes are always locked in your home
node and you can't find the reason, you can put the following lines into your
~/.profile as a stop-gap measure to automatically enable migration:
        if [ -x /proc/$$/lock ]; then                                        
           echo 0 > /proc/$$/lock                                            
However, you should make an effort to find out what the problems is

13.2. Choosing your processes

You will probably want to test your setup before deciding which programs you
want to enable migration for. For example, if you are running KDE2 on a slow
machine and have a significantly faster machine has part of your Mosix
cluster, you might find resource-hungry programs like kmail are migrated out.
This is not a bad thing as such, however, it can lead to a brief moment when
your writing is not displayed on the screen immediately. 

13.3. Java and openMosix

 Green Threads JVM's, allow for migration because each Java thread is a
separate process. Threads other than Java green thread JVM's cannot be
migrated by Linux, so openMosix cannot migrate programs that use them.

  If you have the source so your Java application you might be able to
compile the application native. In this case you might be able to migrate
your applications to another node.

 Gian Paolo Ghilardi wrote a paper titled Consideration on OpenMosix it deals
amongst other topics with Java an dopenMosix.

13.4. openMosix and Hyperthreading

Basically openMosix performance increases with the current Linux scheduler
when Hypethreading is disabled. You can do this by either entering 'noht' as
a boot option or disabling HT in the bios.  

For those who are still wondering what hypetrheading is : Intel explains it

13.5. openMosix and Firewalls

People often have questions regarding openMosix and firewalls. Amit helped me
out on this matter:
from hpc/comm.c:                                                             
#define MIG_DAEMON_PORT         0x3412                                       
#define INFO_DAEMON_PORT        0x3415                                       
converted to decimal, they are: 4660 and 5428 resp. (convert 1234, and not
3412, 'cos of the network-host byte ordering conversions.. Read the IP/TCP/
UDP RFCs for info)

the mig_daemon port is a tcp port, the info_daemon port is udp. Hence tcp/
4660 and udp/5428, Matt also mentions tcp/723 somewhere.  

Chapter 14. (stress)Testing your openMosix installation

14.1. A small Test Script

The fastest way to test your openMosix cluster is by creating a small script
with the following content.
awk 'BEGIN {for(i=0;i<10000;i++)for(j=0;j<10000;j++);}' &                    
I've saved it as test_mosix, now when I want to see If everything works I
start op mosmon and I launch this script for a zillion times as in
for i in `ls /etc/` ; do ./test_mosix ; done                                 
Now watch openMosix kicking in after a few seconds ...

Just pkill awk on the home node to kill'em all ;)  

14.2. Perl Proggie by Charles Nadeau

Perl program to test an openMosix Cluster.

 Here is a is quick program I wrote to test an openMosix cluster. This is
taken from a posting I made to the openMosix-devel mailing list on March 6th,
2002: "Charles wrote this little program (in Perl) to stress test his home
cluster (3 P200MMX and a P166). It is a program simulating different sets of
stocks in a portfolio for a given period of time. The code is well documented
and it should be easy to add/remove stocks and change the average monthly
yield and standard deviation for each stock. Since the problem of portfolio
optimization cannot be solved analytically, it simulate a lot of portfolios
and report the results at the end. Please note that this program does not
take stock correlation into account. It is not finished yet but it's a good
start. I plan to add more code at the end of the program to improve the
reporting format of the data (generating SVG graph on the fly). But the
simulation part works very well. In order to take advantage of the
parallelism offered by openMosix, it uses the Perl module Parallel::?
ForkManager (from CPAN) to span threads that openMosix can then assign to all
the machines of the cluster (it also require another module for the
statistical calculations, don't forget to install both, I provide the URLs in
the comments of the code). Take a look at it and tell me what you think.

#! /usr/bin/perl -w                                                                                                                                                                                                       
# this mill unlock this process and all tis childs                                                                                                                                                                        
sub unlock {                                                                                                                                                                                                              
open (OUTFILE,">/proc/self/lock") ||                                                                                                                                                                                      
die "Could not unlock myself!\n";                                                                                                                                                                                         
print OUTFILE "0";                                                                                                                                                                                                        
# this will count the nodes                                                                                                                                                                                               
sub cpucount {                                                                                                                                                                                                            
 opendir($nodes, $CLUSTERDIR);                                                                                                                                                                                            
 while(readdir($nodes)) {                                                                                                                                                                                                 
 closedir ($nodes);                                                                                                                                                                                                       
 return $howmany;                                                                                                                                                                                                         
my $processes=cpucount;                                                                                                                                                                                                   
print("starting $processes processes\n");                                                                                                                                                                                 
                                                                                                                                                                                                                 , version 0.1                                                                                                                                                                                                
#Perl program that simulate a portfolios for various stock composition for a given period of time                                                                                                                         
#We run various scenarios to find the mix of assets that give the best performance/risk ratio                                                                                                                             
#This method is base on the book "The intelligent asset allocator" by William Bernstein                                                                                                                                   
#Can be used to test an OpenMosix cluster                                                                                                                                                                                 
#This program is licensed under GPL                                                                                                                                                                                       
#Author: Charles-E. Nadeau Ph.D., (c) 2002                                                                                                                                                                                
#E-mail address: charlesnadeau AT hotmail DOT com                                                                                                                                                                         
use Parallel::ForkManager; #We use a module to parallelize the calculation                                                                                                                                                
#Available at;join=and;arrange=file;download=auto;stem=no;case=clike;;age=;distinfo=2589            
use Statistics::Descriptive::Discrete; #A module providing statistical values                                                                                                                                             
#Available at;filetype=%20distribution%20name%20or%20description;join=and;arrange=file;download=auto;stem=no;case=clike;;age=;distinfo=2988 
srand; #We initialize the random number generator                                                                                                                                                                         
#Initializing constant                                                                                                                                                                                                    
$NumberOfSimulation=$processes;  #Number of simulation to run                                                                                                                                                             
$NumberOfMonth=100000; #Number of month for wich to run the simulation                                                                                                                                                    
$NumberOfStock=6; #Number of different stocks in the simulation                                                                                                                                                           
#Portfolio to simulate                                                                                                                                                                                                    
#TODO: Read the stock details from a file                                                                                                                                                                                 
$Stock[0][0]="BRKB"; #Stock ticker                                                                                                                                                                                        
$Stock[0][1]=0.01469184; #Stock average monthly return                                                                                                                                                                    
$Stock[0][2]=0.071724934; #Stock average monthly standard deviation                                                                                                                                                       
$Stock[1][0]="TEST "; #Stock ticker                                                                                                                                                                                       
$Stock[1][1]=-0.01519; #Stock average monthly return                                                                                                                                                                      
$Stock[1][2]=0.063773903; #Stock average monthly standard deviation                                                                                                                                                       
$Stock[2][0]="SPDR"; #Stock ticker                                                                                                                                                                                        
$Stock[2][1]=0.008922718; #Stock average monthly return                                                                                                                                                                   
$Stock[2][2]=0.041688404; #Stock average monthly standard deviation                                                                                                                                                       
$Stock[3][0]="BRKB"; #Stock ticker                                                                                                                                                                                        
$Stock[3][1]=0.01469184; #Stock average monthly return                                                                                                                                                                    
$Stock[3][2]=0.071724934; #Stock average monthly standard deviation                                                                                                                                                       
$Stock[4][0]="TEST "; #Stock ticker                                                                                                                                                                                       
$Stock[4][1]=-0.01519; #Stock average monthly return                                                                                                                                                                      
$Stock[4][2]=0.063773903; #Stock average monthly standard deviation                                                                                                                                                       
$Stock[5][0]="SPDR"; #Stock ticker                                                                                                                                                                                        
$Stock[5][1]=0.008922718; #Stock average monthly return                                                                                                                                                                   
$Stock[5][2]=0.041688404; #Stock average monthly standard deviation                                                                                                                                                       
my $pm = new Parallel::ForkManager($NumberOfSimulation); #Specify the number of threads to span                                                                                                                           
  sub { my ($pid,$ident)=@_;                                                                                                                                                                                              
  print "started, pid: $pid\n";                                                                                                                                                                                           
#We initialize the array that will contain the results                                                                                                                                                                    
for $i (0..$NumberOfSimulation-1){                                                                                                                                                                                        
        for $j (0..$NumberOfStock+3){                                                                                                                                                                                     
                $Results[$i][$j]=0.0; #Equal to 0.0 to start                                                                                                                                                              
for $i (0..$NumberOfSimulation-1){ #Loop on the number of simulation to run                                                                                                                                               
        $Results[$i][0]=$i; #The first column of each line is the number of the simulation                                                                                                                                
        $pm->start and next; #Start the thread                                                                                                                                                                            
                $TotalRatio=1; #The sum of the proprtion of each stock                                                                                                                                                    
                #Here we calculate the portion of each investment in the portfolio for a given simulation                                                                                                                 
                for $j (0..$NumberOfStock-2){ #We loop on all stock until the second to last one                                                                                                                          
                        #TODO: Replace rand by something from Math::TrulyRandom                                                                                                                                           
                        $Results[$i][$j+1]=$Ratio[$j]; #We store the ratio associated to this stock                                                                                                                       
                $Ratio[$NumberOfStock-1]=$TotalRatio; #In order to have a total of the ratios equal to one, we set the last ratio to be the remainder                                                                     
                $Results[$i][$NumberOfStock]=$Ratio[$NumberOfStock-1]; #We store the ratio associated to this stock. Special case for the last stock                                                                      
                $InvestmentValue=1; #Initially the investment value is 1 time the initial capital amount.                                                                                                                 
                my $stats=new Statistics::Descriptive::Discrete; #We initialize the module used to calculate the means and standard deviations                                                                            
                for $j (1..$NumberOfMonth){ #Loop on the number of months                                                                                                                                                 
                        $MonthlyGrowth[$j]=0.0; #By how much did we grow this month. Initially, no growth yet.                                                                                                            
                        #We loop on each stock to find its monthly contribution to the yield                                                                                                                              
                        for $k (0..$NumberOfStock-1){                                                                                                                                                                     
                        $MonthlyGrowth[$j]=$MonthlyGrowth[$j]+($Ratio[$k]*((gaussian_rand()*$Stock[$k][2])+$Stock[$k][1])); #We had the growth for this stock to the stock already calculated for the preceding stocks    
                        $stats->add_data($MonthlyGrowth[$j]); #Add the yield for this month so we can later on have the mean and standard deviation for this simulation                                                   
                        $InvestmentValue=$InvestmentValue*(1+$MonthlyGrowth[$j]); #Value of the Investment after this month                                                                                               
                $Results[$i][$NumberOfStock+1]=$stats->mean(); #Calculate the average monthly growth                                                                                                                      
                $Results[$i][$NumberOfStock+2]=$stats->standard_deviation(); #Calculate the standard deviation of the monthly growth                                                                                      
        $pm->finish; #Finish the thread                                                                                                                                                                                   
$pm->wait_all_children; #We wait until all threads are finished                                                                                                                                                           
#Printing the results                                                                                                                                                                                                     
print "Simulation ";                                                                                                                                                                                                      
for $j (0..$NumberOfStock-1){                                                                                                                                                                                             
        print "Ratio$Stock[$j][0] ";                                                                                                                                                                                      
print "  Mean StdDev YieldRatio\n";                                                                                                                                                                                       
for $i (0..$NumberOfSimulation-1){                                                                                                                                                                                        
        printf "%10d ", $Results[$i][0];                                                                                                                                                                                  
        for $j (1..$NumberOfStock){                                                                                                                                                                                       
                printf "   %6.2f ",$Results[$i][$j];                                                                                                                                                                      
        if($Results[$i][$NumberOfStock+2]!=0) {                                                                                                                                                                           
                printf "%5.4f %5.4f    %5.4f\n", $Results[$i][$NumberOfStock+1], $Results[$i][$NumberOfStock+2], ($Results[$i][$NumberOfStock+1]/$Results[$i][$NumberOfStock+2]);                                         
        } else {                                                                                                                                                                                                          
                printf "%5.4f %5.4f    %5.4f\n", $Results[$i][$NumberOfStock+1], $Results[$i][$NumberOfStock+2], 0;                                                                                                       
#Subroutine to generate two numbers normally distributed                                                                                                                                                                  
#From "The Perl Cookbook", recipe 2.10                                                                                                                                                                                    
sub gaussian_rand {                                                                                                                                                                                                       
        my ($u1, $u2);                                                                                                                                                                                                    
        my $w;                                                                                                                                                                                                            
        my ($g1, $g2);                                                                                                                                                                                                    
        do {                                                                                                                                                                                                              
        } while ($w>=1 || $w==0); #There was an error in the recipe, I corrected it here                                                                                                                                  
        return wantarray ? ($g1,$g2) : $g1;                                                                                                                                                                               

14.3. the openMosix stress-test

by Matt Rechenburg

14.3.1. General description

This stress test is made to test an openMosix cluster + kernel. It will
perform several application + kernel tests for checking the stability and
other features of openMosix (e.g. process migration, mfs, ...). During this
test the cluster will be mostly loaded so you should stop other running
applications before starting it. When it finished it generates a fully
detailed report about each component which was tested.

14.3.2. Detailed description

 The openMosix stress-test runs several programs to check the functionality
of the whole system. In the following part you will find a description of
each test-application:

��*�distkeygen: This applicaton is used to generate 4000 RSA key pairs with
    1024 bits of key length. It is destributed into as many processes as
    processors in your openMosix cluster via fork.
    Requires : gcc compiler and OpenSSL library Copyright (C) 2001 Ying-Hung
    Chen (GPL)
��*�portfolio 'portfolio' is a perl program that simulate a portfolios for
    various stock composition for a given period of time. This method is base
    on the book "The intelligent asset allocator" by William Bernstein.
    This program is licensed under GPL Author: Charles-E. Nadeau Ph.D., (c)
    2002 E-mail address: charlesnadeau AT hotmail DOT com
��*�eatmem : Simply calculates sin+sqrt from a value 1000000 times and
    outputs it outputs the loop count to a file (which will grow a lot) This
    tests is started as many times at once as many processors you have in
    your openMosix cluster automatically.
��*�forkit: The 'forkit' test is similar to the 'eatmem' test but uses fork
    to create multiple process (3*[processors_in_your_openMosix_cluster])
    expect it does not write to files.
��*�mfstest This will create a 10MB file and copy it to all nodes back and
    forth. It is for checking the oMFS capabilities.
��*�kernel syscall test: The Linux Test Project is a joint project with SGI,
    IBM, OSDL, and Bull with a goal to deliver test suites to the open source
    community that validate the reliability, robustness, and stability of
    Linux. The Linux Test Project is a collection of tools for testing the
    Linux kernel and related features. The goal is to improve the Linux
    kernel by bring test automation to the kernel testing effort. Interested
    open source contributors are encouraged to join the project. For more
    informations visit :
��*�moving: The '' will move the '' around
    each node in your openMosix cluster while running the stress-test itself.
    So '' will migrate every minute to another node
    during the test-run. Dependent on how long the test will run on your
    cluster it will be migrated 20-40 times.

14.3.3. Installing the strestest suite

First of all download the rpm or source package from http://

��*�using the source package :
    Unzip and untar the openMosix stress-test with the following commands in
    e.g. /usr/local:
              gunzip omtest.tar.gz                                   
              tar -xvf omtest.gz                                     
    Then 'cd' into the /usr/local/omtest directory and execute:
    This will install the required perl modules and compile the
    test-programs. The installation of these modules requires
    root-privileges. Later you can run the openMosix stress-test also as a
    regular user. (you maybe have to delete old temporary files from root's
    test-runs in /tmp because you won't have the permission to overwrite it
    as regular user) You are ready to run the test now with the command:
��*�using the RPM-package
    There are some requirements to be met when installing the omtest.rpm, you
    will need e.g expect and compat-libstdc++-7.3-2.96.110 (If you are on RH
    8.0) Just install the omtest.rpm with the following command:
              rpm -ihv omtest.rpm                                    
    Now you can start the openMosix stress test with the command:
    (The RPM-package will be installed in /usr/local/omtest) (Please not that
    the RPM wil allso install some perl modules). 

14.3.4. Running the tests

[root@dhcp51 omtest]# ./                                          
starting the openMosix stress test now!                                                  
the results will be saved in : /tmp/openMosix-stress-test-report-03/16/2003-11:27:02.txt 
oMFS is not mounted at /mfs! oMFS-test will be disabled.                                 
Please mount oMFS before running this openMosix-test                                     
You will find instructions how to configure and use oMFS at:                                                         
(return to continue, ctrl-c for cancel)                                                  

IV. Running Applications on openMosix

Table of Contents
15. Improving Compiling Performance
    15.1. Introduction
16. Imaging with openMosix
    16.1. Introduction
    16.2. Povray
17. BioInformatics and openMosix
    17.1. Introduction
    17.2. Blast

Chapter 15. Improving Compiling Performance

15.1. Introduction

This Section is a Work in Progress

Lots of people try to use openMosix as a kind of compile farm, ofthen they
come back very disappointed. This chapter of the howto will try to explain in
which cases your compilations will benefit from openMosix and how to improve
your successlevel.

First of all you have to remember 1 thing. openMosix will not migrate all
processes you start on your cluster, only the ones that will benefit from
migration to another node. For compiling this means that a process has to
last long enough. Kernel compiles typically consist of numerous short
compiles, each of them not being long enough to acutally migrate.

Chapter 16. Imaging with openMosix

16.1. Introduction

This Section is a Work in Progress

 Computer Graphics have always been applications that required a lot of CPU
power, this hasn't changed. Within this chapter I wil demonstrate with some
practical examples how Computer Graphics can benefit from openMosix. 

16.2. Povray

The Persistence of Vision Raytracer is a high-quality, totally free tool for
creating stunning three-dimensional graphics.

Ray-tracing is a rendering technique that calculates an image of a scene by
simulating the way rays of light travel in the real world. However it does
its job backwards. In the real world, rays of light are emitted from a light
source and illuminate objects. The light reflects off of the objects or
passes through transparent objects. This reflected light hits our eyes or
perhaps a camera lens. Because the vast majority of rays never hit an
observer, it would take forever to trace a scene.

These kind of applications can be easily made parrallel by using pvmpovray.
Pvmpovray expects to working on a Beowulf style cluster and spread it's load
to other nodes using pvm. The openMosix way of doing this is the same,
however we just do this on 1 machine and have openMosix do the load spreading
work fo you !

A GREAT Howto on PVM Povray will show you how to setup PVMPovray. Below is a
small summary.

$ cd pvmpov3_1g_2                                                               
$ tar xfz ../povuni_s.tgz                                                       
$ tar xfz ../povuni_d.tgz                                                       
$ ./inst-pvm                                                                    
Trying to apply the patch.                                                      
Searching for rejected files                                                    
Now compile with aimk ( which is a wrapper script provided by the pvm rpm ,
buth which probably won't be in your path.(some of the readers might remember
aimk from other platforms / applications )

If you are on a RH 8.0 box id moved libpng and zlib to .notused .. This in
order to prevent version issues .. with other libpng and zlib versions.
export PATH=$PATH:/usr/share/pvm3/lib                                        
export PVMROOt=/usr/share/pvm3                                               
I then run aimk newunix. Then we start pvm and quit it. The daemon stays

And a last thing that is not known by a novice pvm user is that pvm does use
its own paths, and you have to put pvmpov either in that path or launch it
with the complete pathname.

[root@dhcp71 povray31]# /usr/local/bin/pvmpov -L                             
/usr/src/povray/pvmpov3_1g_2/povray31/include/ +Iskyvase.pov                 
+Oskyvase.tga +NT16 +NW64 +NH64 +v +w1024 +h768                              
Persistence of Vision(tm) Ray Tracer Version 3.1g.Linux.gcc                  
  This is an unofficial version compiled by:                                 
  Jakob Flierl  - PVMPOV Version 3.1g.2                                      
  The POV-Ray Team(tm) is not responsible for supporting this version.       
Copyright 1999 POV-Ray Team(tm)                                              
Never found section  in file                                                 
Initializing PVMPOV                                                          
  Spawning /usr/local/bin/pvmpov with 16 PVM tasks on 1 hosts...             
  ...16 PVM tasks successfully spawned.                                      
  Waiting up to 120s for first slave to start...                             
  Slave 0 successfully started.                                              
Parsing Options                                                              
  Input file: skyvase.pov (compatible to version 3.1)                        
  Remove bounds........On  Split unions........Off                           
  Library paths: /usr/local/lib/povray31 /usr/local/lib/povray31/include     
Output Options                                                               
  Image resolution 1024 by 768 (rows 1 to 768, columns 1 to 1024).           
  Output file: skyvase.tga, 24 bpp PNG                                       
  Graphic display.....Off                                                    
  Mosaic preview......Off                                                    
  CPU usage histogram.Off                                                    
  Continued trace.....Off  Allow interruption...On  Pause when               
  Verbose messages.....On                                                    
Tracing Options                                                              
  Quality:  9                                                                
  Bounding boxes.......On  Bounding threshold: 25                            
  Light Buffer.........On  Vista Buffer.........On                           
Animation Options                                                            
  Clock value....   0.000  (Animation off)                                   
PVM Options                                                                  
  Block Width....      64  Block Height...      64                           
  PVM Tasks......      16                                                    
  PVM Nice.......       5                                                    
  PVM Arch.......                                                            
  PVM Slave...... /usr/local/bin/pvmpov                                      
  PVM WorkingDir. /usr/src/povray/pvmpov3_1g_2/povray31                      
Redirecting Options                                                          
  All Streams to console..........On                                         
  Debug Stream to console.........On                                         
  Fatal Stream to console.........On                                         
  Render Stream to console........On                                         
  Statistics Stream to console....On                                         
  Warning Stream to console.......On                                         
Starting frame 0...                                                          
 Slave 1 at successfully started.              
 Slave 2 at successfully started.              
 Slave 3 at successfully started.              
 Slave 4 at successfully started.              
 Slave 5 at successfully started.              
 Slave 6 at successfully started.              
 Slave 7 at successfully started.              
 Slave 8 at successfully started.              
 Slave 9 at successfully started.              
 Slave 10 at successfully started.             
 Slave 11 at successfully started.             
 Slave 12 at successfully started.             
 Slave 13 at successfully started.             
 Slave 14 at successfully started.             
 Slave 15 at successfully started.             
  0:00:53 86.46 of blocks complete.Not using   
for reassignment (77%)                                                       
  0:00:53 86.98 of blocks complete.Not using   
for reassignment (67%)                                                       
Not using for reassignment (86%)               
Not using for reassignment (85%)               
  0:00:55 89.06 of blocks complete.   640 of  768 lines finished (in frame   
0).Not using for reassignment (65%)            
  0:00:56 91.67 of blocks complete.Not using   
for reassignment (72%)                                                       
  0:00:56 92.71 of blocks complete.Not using   
for reassignment (80%)                                                       
  0:00:57 93.75 of blocks complete.                                          
Slave at has exited.                           
  0:00:57 94.79 of blocks complete.                                          
Slave at has exited.                           
Slave at has exited.                           
  0:00:58 95.83 of blocks complete.                                          
Slave at has exited.                           
  0:00:58 96.35 of blocks complete.   672 of  768 lines finished (in frame   
0).Not using for reassignment (77%)            
Slave at has exited.                           
  0:00:58 97.14 of blocks complete.   688 of  768 lines finished (in frame   
Slave at has exited.                           
  0:00:59 97.92 of blocks complete.                                          
Slave at has exited.                           
  0:00:60 98.44 of blocks complete.   704 of  768 lines finished (in frame   
Slave at has exited.                           
  0:01:03 100.00 of blocks complete.   768 of  768 lines finished (in        
frame 0).                                                                    
Finishing frame 0...rtw. 768                                                 
Waiting for remaining slave stats.                                           
PVM Task Distribution Statistics:                                            
           host name  [ done ] [ late ]           host name  [ done ] [      
late ]                                                                [ 5.21%] [                                    
0.00%]  [ 7.81%] [ 0.07%]                [ 8.85%] [                                    
1.17%]  [ 4.69%] [ 0.00%]                [ 8.85%] [                                    
0.98%]  [ 4.17%] [ 0.00%]                [ 5.21%] [                                    
0.00%]  [ 8.33%] [ 0.52%]                [ 5.21%] [                                    
0.00%]  [ 5.73%] [ 0.72%]                [ 7.29%] [                                    
2.73%]  [ 4.17%] [ 0.00%]                [ 5.21%] [                                    
0.00%]  [ 6.77%] [ 0.13%]                [ 4.69%] [                                    
0.00%]  [ 7.81%] [ 0.00%]                       
POV-Ray statistics for finished frames:                                      
skyvase.pov Statistics (Partial Image Rendered), Resolution 1024 x 768       
Pixels:          303104   Samples:          303104   Smpls/Pxl: 1.00         
Rays:           1192710   Saved:                 0   Max Level: 0/5          
Ray->Shape Intersection          Tests       Succeeded  Percentage           
Cone/Cylinder                  1842227          900504     48.88             
CSG Intersection               2742731          323346     11.79             
CSG Union                      1801008          521692     28.97             
Plane                         20223278        11233348     55.55             
Quadric                        1801008         1196533     66.44             
Sphere                         1801008          461786     25.64             
Bounding Object                1842227          900504     48.88             
Calls to Noise:            1201944   Calls to DNoise:        2108954         
Shadow Ray Tests:          2856188   Succeeded:                85620         
Reflected Rays:             889606                                           
Smallest Alloc:                  9 bytes   Largest:            20508         
Peak memory used:          5643343 bytes                                     
Time For Trace:    0 hours  1 minutes   7.0 seconds (67 seconds)             
    Total Time:    0 hours  1 minutes   7.0 seconds (67 seconds)             
As you can see the application was splitted into differen parts and run
separatly, openMosix then did the job of balancing the load to other

I had good results with 2 to 3 times the the number of cpu's I had available

Chapter 17. BioInformatics and openMosix

17.1. Introduction

17.2. Blast

One of the more frequent used application in this field is Blast, Blast has a
patch available that makes it work smoother with openMosix, but that's not
the only alternative.

First of all there are some known problems with this patch, and other
versions of blast , blast tends to segfault sometimes, this mostly happens
with the preformatted databases you download from the internet. If you run
formatdb on a raw database these errors tend to go away.

Next to the openMosix blast patch a lot of people run MPIBlast Given the fact
that openMosix tends to speed up MPI, adding openMosix to this config might
even give you more power for your money, however we will have to do some
extra research to be able to confirm this.

V. openMosix Development

Table of Contents
18. Getting started with openMosix internals
    18.1. Introduction

Chapter 18. Getting started with openMosix internals

18.1. Introduction

this part has been written by Amit Shah

There's not much documentation available right now for the kernel. I hope to
write some in the coming weeks. Anyways, here's how the sources are laid out:

The openMosix code resides largely in hpc/ and include/hpc. There are lots of
patches to the core kernel files everywhere, right from the arch/i386
directories to mm/, fs/, etc. You need to read up the code which interests
you and think that would matter for the present situation (that shouldn't be
a problem, since you've done kernel coding).

here's what you should expect in each of the source files:

��*� hpc/badops.c: one file to handle all the bad operations: mostly return
    err codes
��*�hpc/balance.c: The load balancer code (load + mem usage + n/w usage)
��*� hpc/comm.c: The intra-cluster communication setup
��*� hpc/config.c: The config code for openMosix: after you run the startup
��*� hpc/decay.c: decay (age) the stats and info collected from other nodes
��*� hpc/deputy.c: Code executed on the deputy: service remote syscalls (ie.
    after the process has migrated), signals, etc.
��*� hpc/dfsa.c: Direct File System Access code: the distributed file system
    abstraction layer
��*� hpc/div.c: the algorithms to do floating point divisions
��*�hpc/export.c: export symbols needed in other files
��*� hpc/freemem.c: to keep track of free, avl. memory and to free it if need
    be. hugely taken from the Linux mm/ code.
��*� hpc/hpcadmin.c: tune openMosix admin values (through /proc/hpc)
��*� hpc/hpcproc.c: The /proc/hpc code is handled here
��*� hpc/info.c: The info daemon: sends and receives (multicast) load+mem
    usage stats throughout the cluster
��*� hpc/init.c: Initialization code: initializes the daemons, etc.
��*� hpc/kernel.c: most of the "core" code: all the important algorithms,
    decisions, etc. made here.
��*� hpc/load.c: calculation of local load, etc.
��*� hpc/mig.c: Code that handles the migration. Code in this file is invoked
    on any migration: deputy->remote, remote->deputy; remote->remote
��*� hpc/prequest.c: handles the process's requests: signals, more memory,
��*� hpc/remote.c: Code executed when the process is on the remote: syscalls
    handling on remote, passing control to deputy, etc.
��*� hpc/rinode.c: fs/ related stuff: used mostly for DFSA
��*�hpc/service.c: setting up daemons, getting memory, etc.
��*�hpc/syscalls.c: handles all the remote syscalls here
��*�hpc/ucache.c: handles the ucache: mostly mm/, fs/ stuff.

the other files like auto_syscalls.c, alternate.c are generated at compile


Table of Contents
19. the openMosix FAQ
    19.1. General
    19.2. Getting, building, installing and running openMosix
    19.3. Kernel Questions
    19.4. File Systems
    19.5. Programming openMosix
    19.6. Resources
    19.7. Miscellaneous
20. PlumpOS FAQ
    20.1. Frequently Asked Questions

Chapter 19. the openMosix FAQ

19.1. General

19.1.1. What is openMosix?:
19.1.2. What does the term single-image clustering mean?:
19.1.3. Does openMosix have a homepage?:
19.1.4.  Are there any mailing lists for openMosix?:
19.1.5.  Can I contribute to the openMosix project?:
19.1.6.  Who is the copyright holder of openMosix?:
19.1.7.  Is openMosix a fork of MOSIX?:
19.1.8.  Why did openMosix split from the MOSIX group?:

19.1.1. What is openMosix?:

The openMosix system is a Linux kernel extension for single-image clustering.
It extends the outstanding MOSIX project, but is instead licensed under the
GNU General Public License (GPL).

19.1.2. What does the term single-image clustering mean?:

There are many varieties of clusters, and a single-image cluster has multiple
copies of a single operating system kernel.

19.1.3. Does openMosix have a homepage?:

Yes. It is at The SourceForge project page is at http://

19.1.4. Are there any mailing lists for openMosix?:

Yes. There are three:

 1. For general discussion, use mailto:, whose general information page
    is at
 2. For developers, use, whose
    general information page is at
 3. Italian Language openMosix Mailing List hosted by Democritos (the INFM
    National Simulation Center in Trieste)

19.1.5. Can I contribute to the openMosix project?:

Yes. The openMosix effort already has more than 10 contributors. Unlike the
Linux kernel maintenance system, Moshe Bar appoints official maintainers and
then gives these maintainers the commit bit to the openMosix CVS source tree,
similarly to FreeBSD.

 Right now we are looking for more experienced kernel hackers to work on new
features like checkpoint/restart.

 Write to if you would like to become an openMosix

19.1.6. Who is the copyright holder of openMosix?:

All MOSIX code is copyright by Professor Amnon Barak of Hebrew University of
Jerusalem. All openMosix code is copyright by Moshe Bar, Tel Aviv. The
openMosix system does not contain any non-GPL (i.e. MOSIX) code.

19.1.7. Is openMosix a fork of MOSIX?:

Originally, openMosix was a fork of MOSIX, but it has evolved into an
advanced clustering platform. The openMosix system no longer contains any
non-GPL (i.e. MOSIX) code.

 Compared to MOSIX, a number of features were added:

A port to the UML (User-mode Linux) architecture                   
New and cleaner migration code                                     
A better load balancer                                             
Much reduced kernel latencies                                      
Support for Dolphin and IA64                                       
A greatly simplified installation processes that uses RPM packaging
A wealth of documentation                                          

19.1.8. Why did openMosix split from the MOSIX group?:

The principal issue was that MOSIX was not licensed with an Open Source

19.2. Getting, building, installing and running openMosix

19.2.1.   Where do I get openMosix?:
19.2.2.  Can I mix MOSIX and openMosix nodes in the same cluster?:
19.2.3.  How do I build openMosix?:
19.2.4. What are userland tools?:

19.2.1. Where do I get openMosix?:

The RPMs and source for openMosix are available from our Downloads/Files
Section. Please read the release notes first!

 Also, Gentoo Linux's emerge sys-apps/openmosix-user and Debian GNU/Linux
openMosix packages are available.

19.2.2. Can I mix MOSIX and openMosix nodes in the same cluster?:

No. Just like the older MOSIX, you should not mix nodes because the protocols
are subject to unannounced changes from version to version. In addition,
every new version has bug fixes which warrant updating to the new kernels.

19.2.3. How do I build openMosix?:

 1. Start by unpacking both the Linux kernel sources and the corresponding
    openMosix distribution in a directory, say /usr/src.
 2. Then
    $ cd /usr/src; tar xzf linux-2.x.xx.tar.gz ;gunzip openMosix2.x.xx.gz
 3. Apply the openMosix patches to the pristine Linux kernel sources with
          $ patch -p1 openMosix2.x.xx-x                              
    The directory /usr/src/linux-2.x.xx now contains the 2.x.xx kernel
    sources with the openMosix patches. Compile and install the resulting
    kernel as usual.

19.2.4. What are userland tools?:

Userland tools are a collection of administrative tools used to examine and
control an openMosix node. 

19.3. Kernel Questions

19.3.1.  What kernel versions does openMosix support?:
19.3.2.  I'm trying to compile an openMosix-patched kernel. What compiler
    version should I use?:
19.3.3.  I've compiled the kernel from the sources. How do I add it to the
    bootloader (LILO, GRUB, other)?:
19.3.4.  I installed a Linux distribution and it says that its kernel is
    x.x.x-x. The openMosix README says not to mix kernel versions. Does that
    mean that the openmosix-x.x.x-y RPM will not work on my machine?:
19.3.5.  What does the phrase the same kernel on every machine mean? Does it
    mean the same kernel version, or the same kernel image?:

19.3.1. What kernel versions does openMosix support?:

The latest Linux kernel supported is 2.4.19. Later versions of the 2.4 series
will be supported, as will kernel versions in the 2.5 series.

19.3.2. I'm trying to compile an openMosix-patched kernel. What compiler
version should I use?:

You should use gcc-2.95.3 as this is the recommended compiler for 2.4
kernels. This is a Linux kernel requirement, not just an openMosix
requirement. However, nothing precludes you from having, on the same system,
gcc-2.95.3 for kernel compiles and gcc-3.x for non-kernel compiles.

 Additional notes: There are many kernel-related issues with gcc-3.x
compilers. Inlining, optimization and page alignment do strange things to
operating systems kernels. The standard Linux kernel is only guaranteed to
compile and work properly with gcc 2.95.3.

 However, the Red Hat gcc 2.96 compiler is 2.95 + RH patches. In this case,
you should ensure you use gcc-2.96-74 or later. gcc-2.96-54 will not build
the kernel correctly. In addition, please pay attention to compiler
optimization. Anything greater than -O2 may not be wise. Similarly, if you
choose to use gcc-2.95.x or derivatives, be sure not to use -fstrict-aliasing
(which, depending on your version of gcc 2.95.x, may necessitate using

19.3.3. I've compiled the kernel from the sources. How do I add it to the
bootloader (LILO, GRUB, other)?:

Treat an openMosix kernel just like any other kernel. The openMosix system is
simply an extension to the kernel, and will be treated like a standard kernel
by your bootloader.

19.3.4. I installed a Linux distribution and it says that its kernel is
x.x.x-x. The openMosix README says not to mix kernel versions. Does that mean
that the openmosix-x.x.x-y RPM will not work on my machine?:

No. It means is that if you install openMosix on your cluster, all your
machines should have the openmosix-x.x.x-y kernel installed. You should not
mix kernels which have different kernel versions, i.e. do not mix
openmosix-x.x.z-x, and openmosix-x.x.x-y, etc.

19.3.5. What does the phrase the same kernel on every machine mean? Does it
mean the same kernel version, or the same kernel image?:

It means the same kernel version. You can build different kernel images of
the same source version to meet the hardware/software needs of a given node.

19.4. File Systems

19.4.1.  What's oMFS, how do I use, and where do I get it?:
19.4.2.  Can somebody explain to me the difference bewteen MFS and DFSA, and
    why I would need DFSA?:

19.4.1. What's oMFS, how do I use, and where do I get it?:

The openMosix File System (oMFS) is the filesystem used by openMosix kernels.
You get it by installing an openMosix kernel on the nodes of your cluster
with oMFS enabled in the kernel-config. (It should be enabled in the
openMosix RPMs by default.)

  You should also enable Direct Filesystem Access (DFSA) which allows a
migrated process to execute many syscalls on the remote node locally without
the need to migrate it back to its home node.

  The use and administration of oMFS is very similar to NFS, but unlike NFS,
oMFS features:

��*�Cache consistency
��*�Timestamp consistency
��*�Link consistency

The DFSA layer on top of oMFS makes sure to move the process to the data,
instead of vice versa, whenever it makes sense.

  Please read more about oMFS and how to use it in earlier chapters of the

19.4.2. Can somebody explain to me the difference bewteen MFS and DFSA, and
why I would need DFSA?:

DFSA stands for Direct File System Access and is an optimization. It allows
remote proccesses to perform some file system system calls locally rather
then sending them to their home node. MFS stands for Mosix File System and
allows all nodes access to all node filesystems. DFSA runs on top of a
cluster filesystem, in this case MFS.

19.5. Programming openMosix

19.5.1.  Generally, how do I write an openMosix-aware program?:
19.5.2.  Can I write openMosix programs in perl?:

19.5.1. Generally, how do I write an openMosix-aware program?:

Write your programs as you normally would. Any processes that you spawn are
candidates for migration to another node.

19.5.2. Can I write openMosix programs in perl?:

Yes. Use the Parallel::ForkManager available from CPAN or directly from http:

19.6. Resources

19.6.1.  Where can I find out technical details about openMosix?:
19.6.2.  What other resources are available?:

19.6.1. Where can I find out technical details about openMosix?:

Here are some links:

��*�Brian Pontz's openMosix source code browser is at http://
��*�openMosix Internals: How openMosix Works is at
��*�LTSP + openMosix: A Quick How-To is at
��*�Distributed OSs: General description of openMosix is at http://

More links at the link section of the howto.

19.6.2. What other resources are available?:

Here are some:

��*�The goal of the Parallel Execution Framework is to create a standalone
    device that allows easy clustering of standard PCs. See http://


19.7. Miscellaneous

19.7.1.  I don't see all my nodes. What's happening?:
19.7.2.  Whats the difference between /etc/ , /etc/ , /etc/
19.7.3.  setpe: the supplied table is well-formatted, but my IP address
    ( is not there!:
19.7.4.  I want to install openMosix but I am afraid my machines are too weak
    for this:
19.7.5.  Under what conditions does VMWare work with openMosix:
19.7.6.  What architectures besides x86 (e.g. SPARC, AXP, PPC...) are
    supported by openMosix?:
19.7.7.  Is there a parallel make tool for openMosix such as MPmake?:

19.7.1. I don't see all my nodes. What's happening?:

When you run 'mosmon', press 't' to see the total number of machines running.
Does it warn you that openMosix is not running?

 If it does, then make sure your machine's IP address is included in /etc/ Don't use If you do, you will probably have
problems with your DHCP server or your DNS nameserver.

 If it does not, then see what machines show up. Do you see only your

 If yes, then your machine is most likely running a firewall and is not
letting openMosix through.

 If not, then the problem is most likely with the machine that doesn't show

 Also: Do you have two NIC cards on a node? If so, you have to edit /etc/
hosts to have a line that has the following format
<non-cluster ip> <cluster-hostname>.<cluster-domain> <cluster-hostname>      
You might also need to set up a routing table, which is an entirely different

 Maybe you used different kernel-parameters on each machine? Especially if
you use the 'Support clusters with a complex network topology' option you
should take care that you use the same value for the also appearing option
'Maximum network-topology complexity support' on each machine.

19.7.2. Whats the difference between /etc/ , /etc/ , /etc/

They represent three stages of Mosix/openmosix growth. The file /etc/ is the orginal Mosix map name, The file /etc/ was an early
openMosix map name (and 'hpc' is still used for the /proc files in
openMosix). The current map name is /etc/

19.7.3. setpe: the supplied table is well-formatted, but my IP address
( is not there!:

You'll need to modify your /etc/hosts file. On Red Hat machines mostly the /
etc/hosts file includes a line like localhost                                      

 If has an IP address of, and if you
looked up you might get as an answer.

 However, if you put                                   localhost                                                          
in your /etc/hosts, openMosix won't complain.

19.7.4. I want to install openMosix but I am afraid my machines are too weak
for this:

A machine is never too weak: I have three P200s (64MB each) and two P166s
(one with 48MB and one with 192MB). Two of them are on 10Base-T and the other
three on 100Base-T. Even with these antiquated machines and "heterogenous"
network, I get perfect load balancing to run simulation programs that I write
in Perl. (Look at our ProgramToTestACluster"). Don't be held back by the fact
your machines are old. To us this is a nice feature of openMosix: you can add
newer machines to an existing cluster as they become available. And you do
not need to have all identical machines. That's fantastic!

 However, a 100Base-T network is recommended! Contributed by Charles Nadeau.

19.7.5. Under what conditions does VMWare work with openMosix:

If you intend to run VMWare under openMosix so that openMosix would
load-balance several instances of that (yes, that works). But, if you want to
run openMosix in several VMWare instances and let these instances load
balance (that fails).

 The first case works. The latter case does not work because VMware has a bug
in its Pentium emulation that makes VMware crash (not openMosix, but the
VMware binary) on the first migration.

19.7.6. What architectures besides x86 (e.g. SPARC, AXP, PPC...) are
supported by openMosix?:

Only IA-32 is currently supported. The port of openMosix to the Intel(r)
Itanium(tm) IA-64 Processor Family is complete. Project plans for openMosix'
second year include porting to the 64-bit AMD Opteron(tm) processor.

19.7.7. Is there a parallel make tool for openMosix such as MPmake?:

You can use regular gcc make. just use make -j #, where the # represents how
many child proccesses to spawn.

Chapter 20. PlumpOS FAQ

20.1. Frequently Asked Questions

20.1.1. What is PlumpOS?
20.1.2. Why would I use PlumpOS?
20.1.3. How does it work?
20.1.4. Where can I go for more help?
20.1.5. Where is your homepage?
20.1.6. The penguins are gonna eat the poor halibut in the logo!

20.1.1. What is PlumpOS?

PlumpOS is a mini linux distribution aimed at an easy way to add nodes to an
openMosix cluster without a lot of work or even thought. The original idea
came from (and current development is inspired by) ClumpOS, the now deceased
project by Jean-David Marrow with a very similar goal for MOSIX clusters.

20.1.2. Why would I use PlumpOS?

The first reason to use PlumpOS is to try out openMosix clusters in a simple
and convenient fashion. The second reason is to add nodes to an existing
cluster without a lot of work. PlumpOS is in no way a replacement for
enterprise clusters nor does it strive to be some kind of super duper cluster
project; it merely presents a quick and easy way to turn your average 586+ PC
into another node for your cluster.

20.1.3. How does it work?

From a developer's standpoint it's somewhat difficult but to the common user
it's quite simple: simply burn an ISO with all the required files on it, pop
it into a computer's CDROM drive, boot up the PC (making sure there's a
working network card and cable installed) and there you have one more
computer to distribute load/forked processes to. Because it's a child/slave
node, you have to already have an openMosix box up and running to run tasks
for PlumpOS computers to process. Without a master node, PlumpOS is pretty
useless. That computer or some other network device must already be serving
DHCP addresses or you'll find yourself configuring all your PlumpOS nodes by
hand (which won't make for a happy network administrator - but then again
that's why we have junior admins ^_^). Also, make sure you have the openMosix
autodiscovery daemon (aka omdiscd) running on your master node. The
autodiscovery daemon can be found into openMosix's userspace-tools package.

20.1.4. Where can I go for more help?

Well, for PlumpOS specific help you should join the PlumpOS mailing list at and ask a
question (that wasn't answered on this FAQ) or go to #
PlumpOS. For openMosix related questions you should join the
openMosix-general or openMosix-devel mailing list at http:// or visit #openMosix.

20.1.5. Where is your homepage?

The official PlumpOS homepage is at You will
find updated versions of this document there, as well as updated news, info,

20.1.6. The penguins are gonna eat the poor halibut in the logo!

Yes, but not to worry: no halibuts were harmed in the making of the logo. The
halibut was found deceased on an ice drift after having suffered a heart
attack. Also, any resemblance the halibut may have to another operating
system's mascot of choice is purely coincidental.

Appendix A. How to produce openMosix's Kernel RPM files

A.1. How to produce openMosix's Kernel RPM files

 A step-by-step guide for the dumb release manager and the adventurous "do it
yourself" RPM packager , by Mirko Caserta

 1. Install a RedHat 8 (psyche) on your machine. This is so far the platform
    used to produce the rpms and it's known to do its job well
 2. Get an updated copy of the "linux-openmosix" module from oM's CVS
    repository - details can be found at
 3. Get the tarball for the Linux Kernel sources which we are going to patch
    and put it in /usr/src/redhat/SOURCES - supposing we're talking about a
    2.4.20 Kernel, get the linux-2.4.20.tar.bz2 file from one of the many mirrors worldwide
 4. Unpack the kernel tarball under /usr/src, ie:
       # cd /usr/src                                                 
       # tar vxjf redhat/SOURCES/linux-2.4.20.tar.bz2                
 5. Make a symbolic link to the directory where you've checked out the
    linux-openmosix module, for instance:
       # ln -s /home/mcaserta/src/linux-openmosix/linux-openmosix \  
 6. copy the .spec file and all the .config files which are found in this
    directory under /usr/src/redhat/SOURCES, ie:
       # cp /usr/src/linux-openmosix/configs/openmosix-kernel.spec \ 
       # cp /usr/src/linux-openmosix/configs/*.config \              
 7.   Now it's time to check the version numbers before we make the patch
    file: make sure the very first lines in
       /usr/src/linux-openmosix/Makefile and                         
       /usr/src/redhat/SOURCES/openmosix-kernel.spec have the correct
    kernel version and openMosix revision number
 8.   Good, time to make the patch (suppose we're releasing a patch for the
    2.4.20 Linux Kernel and the 3rd release of openMosix):
       # cd /usr/src                                                 
       # diff -Naur --exclude=CVS --exclude=configs \                
              linux-2.4.20 linux-openmosix > \                       
       # bzip2 /usr/src/redhat/SOURCES/openMosix-2.4.20-3            
 9. At this point your /usr/src/redhat/SOURCES directory should look like:
       # ls /usr/src/redhat/SOURCES                                   
       kernel-2.4.20-athlon.config      kernel-2.4.20-i686-smp.config 
       kernel-2.4.20-athlon-smp.config  linux-2.4.20.tar.bz2          
       kernel-2.4.20-i386.config        openMosix-2.4.20-3.bz2        
       kernel-2.4.20-i686.config        openmosix-kernel.spec         
10. Now you only need to rpmbuild the whole thing - what I usually do is:
       # cd /usr/src/redhat/SOURCES                                  
       # rpmbuild -ba --target   i386   openmosix-kernel.spec        
       # rpmbuild -bb --target   i686   openmosix-kernel.spec        
       # rpmbuild -bb --target athlon   openmosix-kernel.spec        
    but you can easily build all rpms by calling:
     # rpmbuild -ba --target all_x86  openmosix-kernel.spec          
11. After rpmbuild has done its job, you should have the following files
    under the /usr/src/redhat directory:
      a) RPMS/i386/openmosix-kernel-2.4.20-openmosix3.i386.rpm           
        b) RPMS/i686/openmosix-kernel-2.4.20-openmosix3.i686.rpm         
        c) RPMS/i686/openmosix-kernel-smp-2.4.20-openmosix3.i686.rpm     
        d) RPMS/athlon/openmosix-kernel-2.4.20-openmosix3.athlon.rpm     
        e) RPMS/athlon/openmosix-kernel-smp-2.4.20-openmosix3.athlon.rpm 
        f) RPMS/i386/openmosix-kernel-source-2.4.20-openmosix3.i386.rpm  
        g) SRPMS/openmosix-kernel-2.4.20-openmosix3.src.rpm              
        h) SOURCES/openMosix-2.4.20-3.gz                                 
      a) binary kernel package for i386 UP* machines                    
        b) binary kernel package for i686 UP* machines                  
        c) binary kernel package for i686 SMP** machines                
        d) binary kernel package for athlon UP* machines                
        e) binary kernel package for athlon SMP** machines              
        f) source kernel package for any x86 machine (basically this is 
           useful if you need to have the openMosix kernel headers)     
        g) source kernel package (see point 11)                         
        h) kernel patch file compressed with gzip                       
12. The magic spell to obtain all the files back from the .src.rpm file is: #
    rpm2cpio openmosix-kernel-....src.rpm | cpio -di

Special thanks to Martin H�y for the help while I was trying to get the whole
thing together. 

I hope you find this document useful. At least it is for me since I tend to
forget things a few minutes after I've accomplished them :)

* UP = UniProcessor (i.e. one CPU) ** SMP = Symmetric Multi Processing (i.e.
more than one CPU)

Appendix B. More Info

B.1. irc

Some of the openMosix enthousiasts spend time online helping out people on
irc. We are on on #openMosix. Just join us there to dicuss
your problems , ideas and other stuff about openMosix 

B.2. Further Reading


B.3. Translations

Some people have been working on partial translations of this HOWTO, or just
plain openMosix documentation in their own language.

If you are working on a translation of this document let us know.

B.3.1. Chinese

 Ding Wei has written some documents in Chinese, you can read them at http://

Here is a local copy to the Chinese doc in PDF

B.3.2. Spanish

Together with some collegues Miquel Catal�n Co�thas been working on a spanish
translation of the HOWTO 

B.3.3. Russian

Dmitry Katusubo translated the openmosix website and together with Yuri
Prushinsky he also translated the openMosix HOWTO

B.4. Links


��*�openMosix on Sourcefourge
��*�the openMosix HOWTO
��*�the openMosix FAQ
��*�the openMosix WIKI
��*�the openMosix Community Contributions
��*�  Mosix Debian HOWTO 
��*�  K12 LTSP Mosix HOWTO
��*�Mosix Mandrake Linux Terminal Server Project 
��*� openMOSIXVIEW, a GUI for managing openMosix-Cluster 
��*�  User Mode openMosix, a virtual openMosix cluster running in User-mode 
��*� RxLinux, Web Interface for central configuration and management 
��*�  LTSP+OpenMosix: A Mini How-To 
��*� FuBAR: An openMosix cluster at Texas AM - Corpus Christi  
��*�Charting the Land of Elliptic Curves using openMosix
��*�Italian experiences with openMosix clusters Links to several papers
    presented at the conference. These papers cover many recurring questions
    seen on the openMosix mailing list:
    ��+�Osservatorio Astronomico Cagliari (pdf)Securing an openMosix cluster
        in an untrusted networking environment.
    ��+�D.T.I. dell'Universit� di Milano, Polo didattico e ricerca, Crema
        (pdf) Experiences with Java and C programs on openMosix.
    ��+�Riello Group (pdf) Use of openMosix for parallel I/O balancing on
        storage (backup)
    ��+�INFM & Dept. of Physics University of Napoli (pdf) Documents a number
        of small to large clusters and their uses. (Includes many references
        to software and projects.)
    ��+�Conecta srl (pdf) Contains more information on Kraken, the openMosix
        based game server. Included is how they monitor the cluster's
        temperature via lmsenors and how they improved internode
        communications using iproute2 queue controls.
��*�openMosix with Diskless client
��*�Use networked Linux systems to solve your computing challenges by Daniel


B.5. Mailing List

��*� openMosix mailing list 
��*� openmosix-view mailing list 
��*�ClumpOS mailing list 


Appendix C. Credits

The list of people who deserve credits for this HOWTO is long, I actually
lost track of all the people that should be in here. I often add their names
right next to the parts they have contributed.

If you feel that your name is missing here do not hesitate to contact me and
I'll gladly put your name into the list.

 Scot W. Stevenson

I have to thank Scot W. Stevenson for all the work he did on this HOWTO
before I took over. He made a great start for this document.

Assaf Spanier

worked together with Scott in drafting the layout and the chapters of this
HOWTO. and now promised to help me out with this document.

Matthias Rechenburg

Matthias Rechenburg should be thanked for the work he did on openMosixview
and the accompanying documentation , which we included in this HOWTO.

Jean-David Marrow

is the author of Clump/OS, he contributed the documentation on his
distribution to the HOWTO. 

 Bruce Knox

is the maintainer of the openMosix website, he helps where he can and gives a
lot of feedback !  

Evan Hisey

for putting a lot of effort into putting extra documentation in the WIKI

Charles Nadeau

for putting a lot of effort into putting extra documentation in the WIKI

Louis Zechter

Moshe Bar

For writing the code he wrote and helping out with the docs wherever he knows
the answers !

Amit Shah

for getting started with the openMosix internals

Mirko Caserta

For sending in huge patches to this howto 

Ramon Pons

for proofreading the howto and sending in some advice

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