Newsgroups: comp.parallel.pvm
From: stefan.nonneman@jrc.it
Subject: MCNP4a and PVM3.3.8
Keywords: HAAS,MCNP,PVM
Organization: European Commission - Joint Research Centre - Ispra Site(IT)
Date: 18 Aug 1995 16:10:30 GMT
Message-ID: <412e1m$s7j@dicscs4.jrc.it>

Hi,
As a reaction on a message ( that I lost ) from Mr. Martin Haas I mentioned that
I was installing MCNP together with PVM, and that I had some problems.

Today Friday 18 august 1995 I solved them all, and MCNP4a is working well with
PVM3.3.8. 

What I did !?!?!?

First of all use the official package from RSIC for mcnp4a. 
Modify the patch for a certain platform in a way that the pvm patches will be
activated during the preprocessing. 
Run the prpr program.
split the source code with fsplit.
Modify the call to pvmfconfig in routine mnump.f so that 7 instead of 3 arguments will
be passed during the call. Take care to use dummy's of the right type on the right 
position !!!!!

Compile the resulting code and call it mcnp.pvm. Move the exec file to the right 
directory. In my case the directory is $PVM_ROOT/bin/SUN4 because I am working on
a group of 12 Sun Sparc 10 an 20's.

Run pvm and compose the Virtual machine.
Run the mcnp.pvm code with a command line containing the keyword tasks n with n
a number of tasks less than 32. I took n equal to the number of processors in the 
farm.

The result !!!!!

I have a standard input file that I used for benchmarking on different 
platforms. With NPS=100000 the total CPU time used on 1 machine without pvm and with
-O2 option for the f77 is 13.36 min. With pvm installed the code seems to be
speeded up to 12.36 min. This can be due to occcasional events on the network etc ?

In a farm of 1 SS10/51 7 SS10/41 and 3 SS20/61 with an exec file compiled with the -g 
option the same problem was executed in a total CPU time of 2.83 min.

Probably this result can be improved playing on the network configuration and modifying
mcnp itself.

Mr. Haas could you please communicate this to your friend. Could you bring me in
contact with him ?

Best regards,

Stefan Nonneman



