On Monday 09 April 2007 23:02, Ramon Diaz-Uriarte wrote:

> (Yes, maybe I should check snowFT, but it uses PVM, and I recall a
> while back there was a reason why we decided to go with MPI instead of
> PVM).

There is no reason that you can't run both MPI and PVM on the same cluster.

There is a particular reason that the first implementation we (Na Li, who did 
most of the work, and myself) made used PVM -- at the time (pre MPI 2) it was 
far more advanced than MPI as far as "interactive parallel computing", i.e. 
dispatch parallel functions interactively from the command line, creating and 
manipulating virtual machines on the fly.

Of course, most MPI implementations will save you loads of deci-seconds on 
transfer of medium size messages over the wire, but we weren't interested in 
that particular aspect, more in saving days over the course of a one-off 
program (i.e. development time, which can be more painful that run-time).

Now, PVM had the necessary tools for fault tolerance -- though I thought that 
the recent MPI and newer message passing frameworks might have had some of 
that implemented.

And remember, the point of snow was to provide platform-independent parallel 
code (for which it was the first, for nearly any language/implementation), 
not to run it like a bat-out-of-hell...  (we assumed it would be cheaper to 
buy more machines than to spend a few months finding a budget along with 
sharp programmers).

best,
-tony

[EMAIL PROTECTED]
Muttenz, Switzerland.
"Commit early,commit often, and commit in a repository from which we can 
easily
roll-back your mistakes" (AJR, 4Jan05).

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