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Subject: Re: [OMPI users] How to create multi-thread parallel program using thread-safe send and recv?
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2009-09-28 11:28:31


On Sep 27, 2009, at 1:45 PM, guosong wrote:

> Hi Loh,
> I used MPI_Init_thread(&argc,&argv, MPI_THREAD_MULTIPLE, &provided);
> in my program and got provided = 0 which turns out to be the
> MPI_THREAD_SINGLE. Does this mean that I can not use
> MPI_THREAD_MULTIPLE model?

Correct.

To get Open MPI to support MPI_THREAD_MULTIPLE, you need to configure
and build it with the --enable-mpi-threads switch to OMPI's ./
configure script. We don't build MPI_THREAD_MULTIPLE support by
default because it does add some performance overhead.

-- 
Jeff Squyres
jsquyres_at_[hidden]