Newsgroups: comp.parallel.mpi
From: Matt Beare <M.Beare@uea.ac.uk>
Subject: MPI_Barrier and MPI_Bcast hangups
Organization: University of East Anglia
Date: Mon, 02 Dec 1996 12:57:46 +0000
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Message-ID: <32A2D24A.41C6@uea.ac.uk>

I have just installed MPICH v1.0.13 onto a cluster of DEC Alphas and
have converted a simple Fortran77+PVM application to Fortran77+MPI, for
evaluation purposes.

Using just MPI_Send and MPI_Recv, the program runs fine, but when I put
a MPI_Barrier in at the start and end (for timing purposes) the program
hangs when using 4 processes or more.

Running one of the MPI example programs (fpi) which uses MPI_Bcast,
resulted in similar problems when using 4 or more processes.  The
processes start okay, but then hang.

Running the equivalent C example (cpi) worked fine for any number of
processes.  So I'm beginning to think the problem is related to Fortran.

Can anyone suggest whats going on please. 

Thanks,
	Matt.

-- 
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Matthew Beare              |  Email: M.Beare@uea.ac.uk
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