Newsgroups: comp.parallel.mpi
From: kevin kreeger <kkreeger@cs.sunysb.edu>
Subject: pthreads and MPI on LINUX
Date: Mon, 23 Mar 1998 16:41:12 -0500
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Message-ID: <3516D6F8.1CFB@cs.sunysb.edu>

Hello,

I am using a cluster of 2 processor Pentium II boxes with
LINUX and MPI.  Therefore to utilize the power of the second
processor, I need to thread my programs.

I know that I read MPI is not thread safe.

However, I thought that meant that as long as I did all of my
MPI stuff inside one thread it would be OK. Well, guess what, 
it does not seem to be that way. 

I attempted moving my "-lpthread" library around to different
locations on the line. (I think that pthread library redefines
some of the standard functions, so I thought that may be the problem)

I tried to use the second processor by putting the same node
name in my "-machinefile" datafile twice, but then the program
blew up. (I kindof figured it would since MPI is not thread safe
it is also not multi-process safe but you still have to try it to be
sure)

Has ANYONE else EVER been successful at accomplishing this?

Thanks in advance

-kevin