Thank You Eugene Loh,

It is very important for me to explain the spike at figure!

But I dont know how to hunt the reason and how to check it.

Would you please help me in more practically?

Thank you again.

From: Eugene Loh <Eugene.Loh@sun.com>
To: Open MPI Users <users@open-mpi.org>
Sent: Friday, April 24, 2009 2:16:22 PM
Subject: Re: [OMPI users] MPI_Bcast from OpenMPI

Right. So, baseline performance seems reasonable, but there is an odd spike that seems difficult to explain. This is annoying, but again: how important is it to resolve that mystery? You can spend a few days trying to hunt this down, only to find that it's some oddity that has no general relevence. I don't know if that's really the case, but I'm just suggesting that it may make most sense just to let this one go.

shan axida wrote:

But, exactly the same program gets different result in another cluster.

I mean the result doent have any spike at all.

Second cluster is almost the same features with the previous one

From: Eugene Loh <Eugene.Loh@Sun.COM>
To: Open MPI Users <users@open-mpi.org>
Sent: Friday, April 24, 2009 1:26:14 AM
Subject: Re: [OMPI users] MPI_Bcast from OpenMPI

So, the remaining mystery is the 6x or so spike at 128 Mbyte. Dunno. How important is it to resolve that mystery?