Newsgroups: comp.parallel.pvm
From: meunierp@email.enst.fr (Philippe Meunier)
Subject: Re: PVM 3.3.9 / pvm_upk... End of buffer on SUNMP
Organization: Ecole Nationale Superieure des Telecommunications
Date: 16 Oct 1995 16:16:19 +0100
Mime-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 8bit
Message-ID: <45tt03$31k@khamsin.enst.fr>

Wilhelm Meier <e_meier@unibw-hamburg.de> wrote:
>The only way to get this working is to use even on the SUNMP the
>SUN4SOL2 binaries of the user-programms AND the pvm, pvmd3 ! So I
>think, there is a bug in the shared-memory part of PVM.

I got the same kind of problem when i was using the SUNMP binaries on
more then one host. I think the problem comes from the 1MB message
length limit in the shared memory code. When i was trying to send a 1
MB message to a remote host, one of the two daemon (i don't remember
which one) was hanging because it wasn't able to get enough shared
memory to recv/send the message to the local client. My guess is that
it was trying to allocate memory both for the message and some kind of
header that was needed for the tcp/ip transmission.

I tried to replace

	for (numint = 25; numint < 1000000; numint *= 10) {

with something like

	for (numint = 225000; numint < 250000; numint += 5000) {
	
in timing.c, and i saw that it was hanging for a message size of
around 970-980 kB (from the top of my memory).

So try to change your program so that the messages sent have a length
which is not too close to the 1MB limit...

Philippe

