Newsgroups: comp.parallel.mpi
From: fbreg@cs.vu.nl (Breg F)
Subject: internal error in internal routine
Organization: Fac. Wiskunde & Informatica, VU, Amsterdam
Date: Mon, 22 Jul 1996 13:45:22 GMT
Message-ID: <Duy67n.F2C.0.-s@cs.vu.nl>

Hi,
 
I'm writing a library, using MPI and threads. To do this I
use only non-blocking MPI-functions and protect them using
mutexes, because the info-explorer tells me the MPI-library
is not thread-safe.
 
I've constructed a blocking receive by constantly probing
for incoming messages, using MPI_Iprobe and explicitly
receiving one when one has arrived. I've created a thread,
using the pthreads library, which executes such a receive.
This program sometimes crashes with the following message :
 
ERROR: 0032-114 Internal error:
                      Internal error. in MPI_Iprobe, task 0
 
The same code executed by the main thread does not give any
problems. Is this message a result of using pthreads with
MPI? The info-explorer mentions the incompatibility between
POE and threads. I hoped to solve this using the mutexes.
Is there any way to make this construct work? I really need
the threads together with the MPI-communication.
 
Thanks for any help,
 
Fabian Breg.


