Newsgroups: comp.parallel.pvm
From: Paul Adams <paul@laplace.csb.yale.edu>
Subject: HPPAMP with shared memory and TCP/IP
Organization: Yale University
Date: Thu, 25 Jul 1996 19:21:47 -0400
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Message-ID: <31F8018B.6201@laplace.csb.yale.edu>

Hello,

  I observe very different performance using shared memory and TCP/IP
with the HPPAMP architecture. A program run on 2 CPUs within the same
machine (ie. using shared memory) takes ~250 seconds per CPU, while the
same program run on 2 CPUs in different machines (both with HPPAMP
architecture) via an ATM switch (ie. using TCP/IP) takes ~320 seconds
per CPU. I am using etime to do the program timing so I attribute the
extra CPU to system CPU time. My question:

- is this the behaviour I should expect? if so, why?
- if it is unexpected behaviour, anyone know how to fix it?

  Cheers,
	Paul

-- 
========================================================================
| Paul Adams               Dept. Molecular Biophysics and Biochemistry |
| Postdoctoral Associate   Bass Center, 266 Whitney Avenue             |
| Office: 203-432-5066     Yale University                             |
| FAX:    203-432-6946     New Haven, CT 06511, USA.                   |
| http://xplor.csb.yale.edu/~paul   mailto://paul@laplace.csb.yale.edu |
========================================================================

