[Beowulf] Programming for heartbeat

[Peter St. John]

I'm pretty sure (but correct me if I'm wrong) that Oracle's "message
passing toolkit" would be built on OpenMPI and not the other way around;
OpenMPI is open source, see
http://en.wikipedia.org/wiki/OpenMPI
and does not require a software license from Sun or Oracle.

you can download (free) OpenMPI from this project page:
http://www.open-mpi.org/software/ompi/v1.6/

Oracle is indeed one of the industry partners, as is IBM, but also
government labs like Los Alamos and various Universities.

MPI provides a library so that your programs can pass jobs to other cores;
something like
for i = 1 to 10
  returnarray[i] = CallApplicationAtAnotherNode(i)
next i

along those lines. You want to try it if you want to do something
parallelizable, e.g. send each possible move in the current chess position
to each of many cores, each one simultaneously evaluates the outcome and
returns a result; play the best result. But if you want to add a column of
a million numbers, sending 1000 numbers to each of 1000 processors may take
more time than one processor just adding them up, so that wouldn't be so
parallelizable.

Peter

On Mon, May 6, 2013 at 10:18 PM, Mark Hahn <hahn at mcmaster.ca> wrote:

> > I'm completely new to all this beowulf thing. I've just now connected my
> > 2 PCs using Heartbeat + Pacemaker,
>
> heartbeat/pacemaner are for high-availability cluster,
> whereas beowulf clustering is primarily about high-performance
> or -throughput clustering.  a beowulf cluster may use HA
> techniques, but normally only for support nodes (if at all.)
> (for symmetry, HA clusters do not normally use MPI, and
> rarely provide batch job schedulers, which is normal for HPC clusters).
>
> > I've seen OpenMPI, but it uses Oracle's Message Passing Toolkit. Would
> > you guys know how could I get a program to work in this beowulf?
>
> MPI is a library which permits you to run a program on several
> machines, and have them communicate and synchronize fairly readily.
> this has nothing to do with HA...
>
> does that help?
>
> regards, mark hahn.
> _______________________________________________
> Beowulf mailing list, Beowulf at beowulf.org sponsored by Penguin Computing
> To change your subscription (digest mode or unsubscribe) visit
> http://www.beowulf.org/mailman/listinfo/beowulf
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.beowulf.org/pipermail/beowulf/attachments/20130506/4ecf071e/attachment.html>