Newsgroups: comp.parallel.pvm
From: hzhou@cs.utk.edu (Honbo Zhou)
Subject: Re: Shared memory comm. on HP machines, possible?
Organization: Oak Ridge National Laboratory
Date: 23 Jun 1994 10:03:15 -0400
Message-ID: <2uc4n3INN31l@duncan.cs.utk.edu>

In article <sphruksa.23.00129ACF@galaxy.csc.calpoly.edu> sphruksa@galaxy.csc.calpoly.edu (Suwat Phruksawan) writes:
>Hi,
>       Is there any way to make the local (same host) communications between 
>tasks use shared memory on the HP machines (or any machines that support 
>shared memory)?
>
>      I understand that PVM3.3 doesn't support shared memory comm. for these 
>uniprocessor machines.  But I think it would be much more efficient if we 
>could have shared memory comm. in the project that my friends and I are 
>working on.
>
>     Any suggestion?
>
>Thanks in advance.
>Suwat Phruksawan.
>

I have implemented a shared memory bewteen pvmd and local tasks (over uniprocessor
shared memory) based on PVM3.3b.

Unfortunately, I measured no performance gain. So it is never releasd. Many
people suggested the reason being expensive context switch even you don't
use the even more expensive semaphore...

I would like to know the reason you want to run two PVM tasks on uniproceesor.

If there are enough intersts, we may consider to do it.


Honbo

------
Honbo Zhou                           (615) 576-6129 (W)
Engineerin, Physics, and Mathematics Division  ---- PVM
Oak Ridge National Laboratory, Oak Ridge, TN 37831-6367
          http://www.epm.ornl.gov/~zhou

