[gmx-users] PowerMac Quad Performance

[Tyler Luchko]

Hello everybody,

Has anyone had any experience running GROMACS on a PowerMac Quad  
machine? We have purchased one as a test but have seen very poor  
performance when running the benchmarks.  For example, I have  
compared the results of the d.villin benchmark from the web with that  
on my dual 2.7 GHz PowerMac and our quad 2.5 GHz PowerMac:

2.5 GHz G5 (gromacs.org, v-3.2.1):			15309 ps/day
2.7 GHz G5 (my dual 2.7,compiled w/ gcc-3.3, v-3.3):	15451 ps/day
2.7 GHz G5 (my dual 2.7,precompiled, v-3.3):		13492 ps/day
2.5 GHz G5 (my quad 2.5,compiled w/ gcc-3.3, v-3.3):	 7516 ps/day
2.5 GHz G5 (my quad 2.5,precompiled, v-3.3):		 6475 ps/day
2.5 GHz G5 x 4 (my quad 2.5,compiled w/ gcc-3.3, v-3.3):28800 ps/day

As you can see the Quad is not doing well with the GROMACS code.  I  
have tried the benchmark tool XBench and my own very simple C code  
but have not reproduced these problems.  Any insights or suggestion  
would be greatly appreciated.

Thank you,

Tyler



  ________________________________________________________________
(_    Tyler Luchko                           Ph.D. Candidate    _)
  _)   Department of Physics            University of Alberta   (_
(_    Edmonton, Alberta, Canada                                 _)
  _)   780-492-1063                       tluchko at ualberta.ca   (_
(________________________________________________________________)