performance tuning differences?

[Dan Kirkpatrick]

Any suggestions on pure performance tuning?  Maybe some things to look into?
I'm sure it's "everything" but are there any tricks that have been fairly 
painless and resulted in good return?

We're benchmarking different platforms, some of which with the same hard 
drive/memory/chipset/processor speed, network inconsequential, etc... with 
more than subtle differences.

Just the difference of installing straight RedHat Linux 6.2 vs 7.1 has 
resulted in 5%-20% performance differences depending on code, the higher 
difference being floating point calculation code.

Just wondering what the consensus is for major things to try or avoid.

Thanks,
Dan

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Dan Kirkpatrick                   dkirk at physics.syr.edu
Computer Systems Manager
Department of Physics
Syracuse University, Syracuse, NY
http://www.physics.syr.edu/help/    Fax:(315) 443-9103
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