* IBM PVMe * * IBM PVMe * * IBM PVMe * * IBM PVMe * * IBM PVMe * * IBM PVMe * 
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|  This directory contains a simple Fortran example for PVM and PVMe
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|                                                                        
|  Filename           Style   Description                                  
|  --------           -----   -----------                                  
|  manager.f          MPMD    A basic "hello world" type program
|  worker.f                                                                
|                                                                        
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|  Please direct any questions, comments or suggestions                  
|  to karin@cam.nist.gov.                                                
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This directory includes the following files:

README.pvm
README.pvme  (this file)  * IBM PVMe * 
make.pvme
make.pvm
manager.f
worker.f

To interactively run the sample program under ** IBM's PVMe ** :

0) If this is your first use of the interactive nodes, make sure you
   have read and followed the instructions in ../README.FIRST !!
   You will be asked to add lines to your .cshrc file, copy the
   sample directory to your own area, 
      AND LOGIN TO ONE OF THE INTERACTIVE NODES (grand17-20)

1) After logging into an interactive node, switch to the IBM PVMe 
   environment:

   prompt> startpvme

     (If pvme is your default environment, set in your .cshrc file,
      and you haven't switched to pvm, then you can skip the
      startpvme step.  See ../README.FIRST for more information.)

   In your copy of the sample directory, type:

   prompt> make -f make.pvme

   The makefile will direct the compilation and linking of the 
   programs.  The executables are created in the current directory
   in this example, but this can be changed to the default executable
   directory, $HOME/pvm3/bin/RS6K, by editing the EXEDIR entry in 
   the makefile.  It's highly recommended that you *first* run through
   the example "as is", and then experiment with modifications after
   you've confirmed that the basic example works for you.

2) Unlike the ORNL PVM example, you need not create a hostfile. 
   The Resource Manager handles the machine setup for you.
   At this point, you should should check the PVMEPATH environment
   variable and change it as necessary to point to the directory where 
   your executables reside.   The default is $HOME/pvm3/bin/RS6K.
   For example, the command

   prompt> setenv PVMEPATH `pwd`

   will set the executable path to be the current directory 
   (required for this example).
   
3) In the sample directory, start the PVM daemon on the nodes of the 
   interactive pool by typing:

   prompt> pvmd3 &          <-- NOTE: the ampersand is important!
   - or -                       If omitted, you must push the job    
   prompt> pvmd3e &             to the background to continue.

   ( pvmd3 and pvmd3e are aliased to the same command, 
   so you may use whichever you prefer.)
 
   This (in effect) requests a single user "lock" on the switch.

   If the switch is available, you will see output from PVMD, and
   finally the ready message:

   PVMD: Ready for 4 hosts...

   If someone else has accessed the switch, you will be prompted to
   wait a while and retry.

   A similar will result if YOU have already accessed the switch. 
   The error message

   PVMD: Error while allocating node , capacity has been exceeded.

   indicates that you already have accessed the switch, and must
   halt the daemon if you wish to restart it.
   

4) Check the configuration through the pvm console:
  
   prompt> pvm       [RETURN]
   pvmd already running.
   pvm> conf         [RETURN]
   4 hosts, 1 data format
                       HOST     DTID     ARCH   SPEED
                    grand17  fff0001     RS6K    1000
                    grand18  fff0002     RS6K    1000
                    grand19  fff0003     RS6K    1000
                    grand20  fff0004     RS6K    1000
   pvm> quit         [RETURN]
   prompt>

  (Other responses, such as only one host being listed, are a sign that
   something has not gone right.  Please contact karin@cam.nist.gov.)

5) Run the program by typing:
 
   manager

   You will be prompted to enter the number of processes you wish
   to spawn.  

   *** IMPORTANT ***:  Since this is PVMe, there is a hard limit on 
   the number of PVM processes, and this cannot exceed the number of
   processors in the virtual machine.  Therefore, you must enter a number
   ** less than or equal to 3 **; choosing a larger input value will 
   result in failure of the program!

   Run the program as many times as you like to verify the output....

6) Examine the results file generated by the manager program:
  
   prompt> cat manager.results

7) Upon completion, halt PVMe:

**   This step is VERY IMPORTANT, since you must release the switch   **
**   before anyone else has access to it.  DO NOT FORGET THIS STEP!   **

   prompt> pvm    [RETURN]
   pvm> halt      [RETURN]
  

8) Clean up...  type:

   prompt> make -f make.pvme new
 
   This will remove the executable, object, output and error files,
   to restore the directory to its original state.
 

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|  Again,                                                          
|  please direct any questions, comments or suggestions            
|  to karin@cam.nist.gov.                                          
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