[gmx-users] P4 vs P3 performance ? Special compilation options ?

[Erik Lindahl]

David van der Spoel wrote:

>On Tue, 26 Mar 2002, Marc Baaden wrote:
>
>>I just did a quick but pertinent benchmark, comparing
>>a single-processor job on a 1.266 GHz PIII versus the
>>same job on a 1.7 GHz PIV (Xeon) .. and the Xeon is
>>slower ! taking about 10% longer.
>>
>>Is this right (eg the effect of the increased pipeline
>>length in the P4's) ? Or are there some special compilation
>>options to get the Gromacs code on Xeons at high speed ?
>>
>
>Hm, how big is the system? Your P3 probably has a larger cache than the P4 
>
The 1.266 GHz PIII is almost certainly the Tulatin core,  which is 
rumored to have a couple of minor improvements and of course has a 
larger cache. That's about the performance I would expect actually, as 
you said yourself the longer pipeline requires a higher frequency.

Cheers,

Erik