BTW, What kind of threads Open MPI supports ? I found in the https://svn.open-mpi.org/trac/ompi/browser/trunk/README that we support MPI_THREAD_MULTIPLE, and found few unclear mails about MPI_THREAD_FUNNELED and MPI_THREAD_SERIALIZED. Also found nothing in FAQ :(. Thanks,Lenny.
On Thu, Jul 2, 2009 at 6:37 AM, rahmani <m_rahman...@me.iut.ac.ir> wrote: > Hi, > Very thanks for your discussion > > ----- Original Message ----- > From: "Jeff Squyres" <jsquy...@cisco.com> > To: "Open MPI Users" <us...@open-mpi.org> > Sent: Tuesday, June 30, 2009 7:23:13 AM (GMT-0500) America/New_York > Subject: Re: [OMPI users] enable-mpi-threads > > On Jun 30, 2009, at 1:29 AM, rahmani wrote: > > > I want install openmpi in a cluster with multicore processor. > > Is it necessary to configure with --enable-mpi-threads option? > > when this option should be used? > > > > > Open MPI's threading support is functional but not optimized. > > It depends on the problem you're trying to solve. There's many ways > to write software, but two not-uncommon models for MPI applications are: > > 1. Write the software such that MPI will launch one process for each > core. You communicate between these processes via MPI communication > calls such as MPI_SEND, MPI_RECV, etc. > > 2. Write the software that that MPI will launch one process per host, > and then spawn threads for all the cores on that host. The threads > communicate with each other via typical threaded IPC mechanisms > (usually not MPI); MPI processes communicate across hosts via MPI > communication calls. Sometimes MPI function calls are restricted to > one thread; sometimes they're invoked by any thread. > > So it really depends on how you want to write your software. Make > sense? > > -- > Jeff Squyres > Cisco Systems > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users >
