From: Srinidhi <srinidhi@ece.neu.edu>
Newsgroups: comp.parallel.mpi,comp.parallel.pvm
Subject: Re: Poor MPI performance with collection of Linux workstations
Date: Wed, 17 Mar 1999 15:07:04 -0500
Organization: Northeastern University, Boston
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Xref: ukc comp.parallel.mpi:4773 comp.parallel.pvm:8140


Harvey J. Stein wrote:

>  > I don't have an answer to your problem, but I have a similar problem.
>  > I'm running Linux and have just recently upgraded all machines to the
>  > 2.2.3 kernel, hoping my problems would be solved. My problems persist. I
>  > have nine machines, one of which is a 4-processor box.
>
> Are they small packets?  If so, here's a patch from the linux-kernel
> mailing list that might help:

I have a similar problem. A 1 Kbyte or larger packet takes less time (~ 1ms) than
a 4 byte mesage (~15ms). This is for PVM on Linux (Redhat 5.1). Does this patch
also fix the problem in PVM? PVM does not use TCP/IP, AFAIK.

Thanks,
-Srinidhi