From: Johannes Zellner <johannes@zellner.org>
Newsgroups: comp.parallel.mpi
Subject: timing for Wait(all|any)
Date: Thu, 8 Jul 1999 00:56:56 +0200
Organization: University of Karlsruhe
Message-Id: <Pine.LNX.4.10.9907080046420.3782-100000@krispc6.physik.uni-karlsruhe.de>
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Xref: ukc comp.parallel.mpi:5293


recently I tryed a one-master - multiple-servers program.

The master sends jobs to the servers (Send) and sets up (Irecv)'s
for each server. Then it goes to a (Waitany) and if this returns
does another (Send)/(Irecv) for the particular Waitany's Request.source().

As the server jobs take quite a while compared to the master-server
traffic, I supposed my master to eat almost no cpu.

But: running this on a single machine with for example `-np 3'
     and each process gets about 33% cpu, also the master.
     what's going on there? (How is the Wait stuff implemented)

Or: HOWTO program a smart master ?

Any hints would be much appreciated.

--
   Johannes