[mpich-discuss] Latency or the B/W, which is the bottleneck for most MPI codes?

[junli gu]

Hi everyone:

  I am wondering to most MPI codes, which is the performance bottleneck, the
latency or the B/W?

  I am doing research to optimize the cache-coherent shared memory
architecture to run MPI codes more efficiently. Although I am trying to
reduce the latency for message data transferring, then I realized that maybe
the B/W is the real bottleneck. I have heard the comments that most
well-written MPI codes  are not latency-sensitive but B/W sensitive. So
instead of making single message transfer faster, increasing the B/W to
transfer the chunk of data faster is the right way to improve performance.

  Can you give us some comments about this?

  Thank you in advance!

-- 
************************************************
Junli Gu--谷俊丽
Coordinate Science Lab
University of Illinois at Urbana-Champaign
************************************************
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/mpich-discuss/attachments/20100305/ae50f98d/attachment.htm>