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?