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From: Brock Palen (brockp_at_[hidden])
Date: 2006-06-13 10:38:23

Ill provide new numbers soon with the --mac mpi_leave_pinned 1
I'm currious how does this affect real application performace? This
ofcourse is a synthetic test using NetPipe. For regular apps that
move decent amounts of data but want low latency more.
Will that be affected?

Brock Palen
Center for Advanced Computing

On Jun 13, 2006, at 10:26 AM, George Bosilca wrote:

> Unlike mpich-gm, Open MPI does not keep the memory pinned by default.
> You can force this by ading the "--mca mpi_leave_pinned 1" to your
> mpirun command or by adding it into the Open MPI configuration file
> as specified on the FAQ (section performance). I think that should be
> the main reason what you're seeing a such degradation of performances.
> If this does not solve your problem, can you please provide the new
> performance as well as the output of the command "ompi_info --param
> all all".
> Thanks,
> george.
> On Jun 13, 2006, at 10:01 AM, Brock Palen wrote:
>> I ran a test using openmpi-1.0.2 on OSX vs mpich-1.2.6 from
>> mryicom and i get lacking results from OMPI,
>> at point point there is a small drop in bandwidth for both MPI
>> libs, but open mpi does not recover like mpich, and further on you
>> see a decreese in bandwidth for OMPI on gm.
>> I have attached in png and the outputs from the test (there are
>> two for OMPI )
>> <bwMyrinet.png>
>> <bwOMPI.o1969>
>> <bwOMPI.o1979>
>> <bwMPICH.o1978>
>> Brock Palen
>> Center for Advanced Computing
>> brockp_at_[hidden]
>> (734)936-1985
>> _______________________________________________
>> users mailing list
>> users_at_[hidden]
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