gromacs benchmark and quad Xeons

Jakob Oestergaard jakob at unthought.net
Tue Jun 18 11:48:10 PDT 2002


On Tue, Jun 18, 2002 at 02:14:02PM -0400, Velocet wrote:
...
> Are the original rpms for gromacs which are generally compiled for P2/MMX
> going to be absolutely the worst possible situation for a Xeon? Or should
> they work relatively near best-speed (minus missing SSE and SSE2 instructions,
> though I dont even know if GCC gives the full set of either for a hand
> compile). 
> 
> What's wrong here? Any ideas?

I don't know gromacs, but I know that one bad compiler switch can mean
a 10 *times* difference in performance. Easily.

For performance testing/tuning I certainly wouldn't recommend using code
you haven't compiled yourself.

Also make sure that you use a compiler version that you are familiar
with. There are *so* many possible variables - better have as few
unknowns as possible.

-- 
................................................................
:   jakob at unthought.net   : And I see the elder races,         :
:.........................: putrid forms of man                :
:   Jakob Østergaard      : See him rise and claim the earth,  :
:        OZ9ABN           : his downfall is at hand.           :
:.........................:............{Konkhra}...............:



More information about the Beowulf mailing list