CSAM - Parallel processing

Using PVM (3.3.10) in the CSAM Department at IIT

This page contains information about the PVM & XPVM setup for users of the deltas cluster. There is extensive PVM information and documentation available on the WWW. A good starting point is the Oak Ridge National Laboratory - Computer Sciences Group where the PVM package was developed.

Changes to your environment
- standard configuration (strongly recommended)
- customized configuration
Compiling a PVM application
Run a PVM application
Help

Changes to your environment - standard configuration

Here is what you need to do to start using PVM on the deltas (for csh users).

Add these lines to your .cshrc file:

     setenv PVM_ROOT /a/apps/pvm3 
     setenv PVM_ARCH SGI5 
     set path=($path $PVM_ROOT/lib/SGI5) 
     setenv XPVM_ROOT /a/apps/xpvm

Make sure you don't have anything in .cshrc that will attempt to do I/O (read from the keyboard or write something on the console), since this will interfere with the PVM start-up process. If, for instance, you have a line that reads

     news

then move this into the .login file since `news' will attempt to print a message.

Create the directory where you will keep your PVM application(s)

     mkdir ~/pvm3
     mkdir ~/pvm3/bin
     mkdir ~/pvm3/bin/SGI5

Create a file called .rhosts in your home directory with the name of the host from which you will start pvm: if you plan to start pvm from delta5, for instance, then the file .rhosts will contain:

     delta5

If you plan to be able to start PVM from more than one host, then add the name of each of them in the .rhosts file, one per line.

Set proper permissions for the .rhosts file:

     chmod go-rwx .rhosts

In the ~/pvm3/bin/SGI5/ create a host file (the name is up to you, but let's say it is myhostfile) which lists all the hosts on which the PVM daemon will be started:

     delta5 
     delta0 
     delta1 
     delta2

The above host file assumes you'll be using up to four hosts, with their names listed at the beginning of each line. If you start the PVM daemons using pvmd3, then a daemon will be started on each host listed in myhostfile.

Changes to your environment - customized configuration

We strongly recommend you to use a standard setup for your PVM configuration. Many software tools developed around PVM rely on the standard configuration to do their work: using a non-standard configuration calls for trouble in the future when you will try to use some of those tools.

The custmized environment described below allows you to do your work in a different directory than the standard ~/pvm3/bin/SGI5/

Here is what you need to do to start using PVM on the deltas (for csh users).

Add these lines to your .cshrc file:

     setenv PVM_ROOT /a/apps/pvm3 
     setenv PVM_ARCH SGI5 
     set path=($path $PVM_ROOT/lib/SGI5) 
     setenv XPVM_ROOT /a/apps/xpvm

Make sure you don't have anything in .cshrc that will attempt to do I/O (read from the keyboard or write something on the console), since this will interfere with the PVM start-up process. If, for instance, you have a line that reads

     news

then move this into the .login file since `news' will attempt to print a message.

Create the directory where you will keep your PVM application(s)

     cd
     mkdir my_pvm

Create a file called .rhosts in your home directory with the name of the host from which you will start PVM: if you plan to start PVM from delta5, for instance, then the file .rhosts will contain:

     delta5

Set proper permissions for the .rhosts file:

     chmod go-rwx .rhosts

Assuming that you want to keep your PVM executables in the directory called my_pvm, under your home directory, create in that directory a host file (the name is up to you, but let's say it is myhostfile) with the following contents:

     delta5   ep=$HOME/my_pvm   wd=$HOME/my_pvm 
     delta0   ep=$HOME/my_pvm   wd=$HOME/my_pvm 
     delta1   ep=$HOME/my_pvm   wd=$HOME/my_pvm 
     delta2   ep=$HOME/my_pvm   wd=$HOME/my_pvm

The above host file assumes you'll be using up to four hosts, with their names listed at the beginning of each line.

Compiling a PVM application

Include the needed PVM header file in each file of your application where pvm calls are made. If your application is written in C, then do

     #include "pvm3.h"

Compile your application making sure that
- the PVM header files are found ( -I/a/apps/pvm3/include )
- the PVM directories are searched before any others ( -L/a/apps/pvm3/lib/SGI5 )
- needed libraries are available for linking ( -lpvm3 )

A makefile which builds an executable from two source files can be downloaded.

Run the PVM executable

Start the PVM daemon on all machines listed in myhostfile

     pvmd3 myhostfile &

Type the name of the executable at your UNIX prompt

The other option is to start XPVM by typing xpvm at your UNIX prompt: this will automatically start the daemons. Beware that the start-up process may take a few seconds.

An example

Change your working directory

     cd ~/pvm3/bin/SGI5/

Copy the example files in your working directory

     cp /a/apps/pvm3/examples/hello.c  .
     cp /a/apps/pvm3/examples/hello_other.c  .

Download the makefile in your PVM working directory
Build the executables

     make -f make_hello

Start the PVM daemon, if it's not already running, on the hosts listed in your hostfile (let's assume it is called myhostfile)

     pvmd3 myhostfile &

Run the example (issue the command several times)

     hello
     hello
     hello
     hello

Local help

For online PVM help try:

     man -M /a/apps/pvm3/man pvm_intro

Some documentation is available in /a/apps/pvm3/doc/

XPVM can be started with some flags in the command line. To learn which flags are available do

     xpvm -HELP

Yes, you use capitals!

Back to Parallel Processing in the CSAM Department at IIT

This page has been created (May 26, 1996) by: Virgil Bistriceanu - virgil@csam.iit.edu
This page is maintained by: Virgil Bistriceanu - virgil@csam.iit.edu
Last update: September 25, 1996