Newsgroups: comp.parallel.mpi
From: Jim Tuccillo <jjt@radia1.com>
Subject: Re: reduction workspace
Organization: http://www.supernews.com, The World's Usenet: Discussions Start Here
Date: Mon, 20 Jul 1998 17:14:37 -0400
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Message-ID: <35B3B33D.1CFB@radia1.com>

The MPI standard would lead you to the conclusion that you must supply
different arguments for the send and receive buffers. This doesnt mean
that it wont work on some systems if you supply the same argument. The
prudent choice is to supply different arguments.

 
Richard Barrett wrote:
> 
> Hey,
> 
> Reductions require a separate input and output
> argument. Must these be different memory locations?
> That is, can I use
> 
>  MPI_Reduce( &max, &max, 1, ... );
> 
> Richard