Re: [OMPI users] Open MPI vs IBM MPI performance help

2010-12-22 Thread Eugene Loh 

I'm curious if that resolved the issue.

David Singleton wrote:


http://www.open-mpi.org/faq/?category=running#oversubscribing

On 12/03/2010 06:25 AM, Price, Brian M (N-KCI) wrote:

Additional testing seems to show that the problem is related to 
barriers and how often they poll to determine whether or not it's 
time to leave.  Is there some MCA parameter or environment variable 
that allows me to control the frequency of polling while in barriers?


From: users-boun...@open-mpi.org [mailto:users-boun...@open-mpi.org] 
On Behalf Of Price, Brian M (N-KCI)

Sent: Wednesday, December 01, 2010 11:29 AM
To: Open MPI Users
Cc: Stern, Craig J
Subject: EXTERNAL: [OMPI users] Open MPI vs IBM MPI performance help

OpenMPI version: 1.4.3
Platform: IBM P5, 32 processors, 256 GB memory, Symmetric 
Multi-Threading (SMT) enabled
Application: starts up 48 processes and does MPI using MPI_Barrier, 
MPI_Get, MPI_Put (lots of transfers, large amounts of data)
Issue:  When implemented using Open MPI vs. IBM's MPI ('poe' from HPC 
Toolkit), the application runs 3-5 times slower.
I suspect that IBM's MPI implementation must take advantage of some 
knowledge that it has about data transfers that Open MPI is not 
taking advantage of.

Any suggestions?

Re: [OMPI users] Open MPI vs IBM MPI performance help

2010-12-03 Thread Nysal Jan 
Collecting MPI Profile information might help narrow down the issue. You
could use some of the tools mentioned here -
http://www.open-mpi.org/faq/?category=perftools

--Nysal

On Wed, Dec 1, 2010 at 11:59 PM, Price, Brian M (N-KCI) <
brian.m.pr...@lmco.com> wrote:

>  OpenMPI version: 1.4.3
>
> Platform: IBM P5, 32 processors, 256 GB memory, Symmetric Multi-Threading
> (SMT) enabled
>
> Application: starts up 48 processes and does MPI using MPI_Barrier,
> MPI_Get, MPI_Put (lots of transfers, large amounts of data)
>
> Issue:  When implemented using Open MPI vs. IBM’s MPI (‘poe’ from HPC
> Toolkit), the application runs 3-5 times slower.
>
> I suspect that IBM’s MPI implementation must take advantage of some
> knowledge that it has about data transfers that Open MPI is not taking
> advantage of.
>
> Any suggestions?
>
> Thanks,
>
> Brian Price
>
>
>
> ___
> users mailing list
> us...@open-mpi.org
> http://www.open-mpi.org/mailman/listinfo.cgi/users
>

Re: [OMPI users] Open MPI vs IBM MPI performance help

2010-12-02 Thread David Singleton 


http://www.open-mpi.org/faq/?category=running#oversubscribing

On 12/03/2010 06:25 AM, Price, Brian M (N-KCI) wrote:

Additional testing seems to show that the problem is related to barriers and 
how often they poll to determine whether or not it's time to leave.  Is there 
some MCA parameter or environment variable that allows me to control the 
frequency of polling while in barriers?
Thanks,
Brian Price

From: users-boun...@open-mpi.org [mailto:users-boun...@open-mpi.org] On Behalf 
Of Price, Brian M (N-KCI)
Sent: Wednesday, December 01, 2010 11:29 AM
To: Open MPI Users
Cc: Stern, Craig J
Subject: EXTERNAL: [OMPI users] Open MPI vs IBM MPI performance help

OpenMPI version: 1.4.3
Platform: IBM P5, 32 processors, 256 GB memory, Symmetric Multi-Threading (SMT) 
enabled
Application: starts up 48 processes and does MPI using MPI_Barrier, MPI_Get, 
MPI_Put (lots of transfers, large amounts of data)
Issue:  When implemented using Open MPI vs. IBM's MPI ('poe' from HPC Toolkit), 
the application runs 3-5 times slower.
I suspect that IBM's MPI implementation must take advantage of some knowledge 
that it has about data transfers that Open MPI is not taking advantage of.
Any suggestions?
Thanks,
Brian Price

Re: [OMPI users] Open MPI vs IBM MPI performance help

2010-12-02 Thread Price, Brian M (N-KCI) 
Additional testing seems to show that the problem is related to barriers and 
how often they poll to determine whether or not it's time to leave.  Is there 
some MCA parameter or environment variable that allows me to control the 
frequency of polling while in barriers?
Thanks,
Brian Price

From: users-boun...@open-mpi.org [mailto:users-boun...@open-mpi.org] On Behalf 
Of Price, Brian M (N-KCI)
Sent: Wednesday, December 01, 2010 11:29 AM
To: Open MPI Users
Cc: Stern, Craig J
Subject: EXTERNAL: [OMPI users] Open MPI vs IBM MPI performance help

OpenMPI version: 1.4.3
Platform: IBM P5, 32 processors, 256 GB memory, Symmetric Multi-Threading (SMT) 
enabled
Application: starts up 48 processes and does MPI using MPI_Barrier, MPI_Get, 
MPI_Put (lots of transfers, large amounts of data)
Issue:  When implemented using Open MPI vs. IBM's MPI ('poe' from HPC Toolkit), 
the application runs 3-5 times slower.
I suspect that IBM's MPI implementation must take advantage of some knowledge 
that it has about data transfers that Open MPI is not taking advantage of.
Any suggestions?
Thanks,
Brian Price

[OMPI users] Open MPI vs IBM MPI performance help

2010-12-01 Thread Price, Brian M (N-KCI) 
OpenMPI version: 1.4.3
Platform: IBM P5, 32 processors, 256 GB memory, Symmetric Multi-Threading (SMT) 
enabled
Application: starts up 48 processes and does MPI using MPI_Barrier, MPI_Get, 
MPI_Put (lots of transfers, large amounts of data)
Issue:  When implemented using Open MPI vs. IBM's MPI ('poe' from HPC Toolkit), 
the application runs 3-5 times slower.
I suspect that IBM's MPI implementation must take advantage of some knowledge 
that it has about data transfers that Open MPI is not taking advantage of.
Any suggestions?
Thanks,
Brian Price