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Subject: [OMPI users] 2 to 1 oversubscription
From: Robert Kubrick (robertkubrick_at_[hidden])
Date: 2009-07-11 17:16:06


The Open MPI FAQ recommends not to oversubscribe the available cores
for best performances, but is this still true? The new Nehalem
processors are built to run 2 threads on each core. On a 8 sockets
systems, that sums up to 128 threads that Intel claims can be run
without significant performance degradation. I guess the last word is
to those who have tried to run some benchmarks and applications on
the new Intel processors. Any experience to share?

http://www.open-mpi.org/faq/?category=running#oversubscribing
http://en.wikipedia.org/wiki/Simultaneous_multithreading
http://communities.intel.com/community/openportit/server/blog/
2009/06/11/nehalem-ex-brings-new-economics-to-scalable-systems