From: Angel Valtchev <val@nat.bg>
Newsgroups: comp.parallel.mpi
Subject: Problem with dynamic virtual process creation under mpich 1.1.2
Date: Fri, 19 Mar 1999 12:40:28 +0200
Organization: Naturella Agency Ltd
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Xref: ukc comp.parallel.mpi:4780


Excuse me for my bad english.
I'm new in MPI and I have a problem with dynamic virtual process
creation.
I use mpich 1.1.2 under network of PC workstations with Linux Slackware
3.6, kernel 2.2.3. Here is the situation:
At the first moment i run one server process on every machine and
initialize MPI. After this in random moment I need to start and stop
plenty of virtual processes which must use MPI. But in MPI 1.1 standart
it is forbidden to use fork() after initialization of MPI ( it is alowed
in MPI 2 - am I wright ? ), so I decide to trick and try to use POSIX
threads ( actualy linuxthreads-0.7.1 which are kernel-based). My
questions are:
1. Is mpich 1.1.2 thread-safe? (if it is - there is no problem at all,
but I am almost sure it's not )
2. Is there some other similar solution of the problem and where can I
read something about?
3. Is there any solution at all ? ( includin other MPI implementations
or may be somthing else ...)

I'll be very glad to read any answers which can help me.
Thank You in advance.

Angel Valtchev
Student in Technical University of Varna
Bulgaria