[Beowulf] Nehalem and Shanghai code performance for our rzf example
Joe Landman
landman at scalableinformatics.com
Sat Jan 17 10:16:28 PST 2009
Kevin Abbey wrote:
> Hi Joe,
> Can that 9% difference be due to the Intel capability to overclock one
> core and turn the others off?
Hi Kevin:
Not sure. May investigate at some point, but we should see a marked
decrease in speedup over 4 threads on 4 cores if this is the case.
> Or is does this Intel feature require manual switch somewhere?
No 'switches'. Pure gcc, using -O3 flag, nothing "funky" in the code.
Joe
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Joseph Landman, Ph.D
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