Author: Robert Hyatt
Date: 13:17:31 01/02/02
Go up one level in this thread
On January 02, 2002 at 15:41:41, Peter Berger wrote: >On January 02, 2002 at 15:34:55, David Rasmussen wrote: > >>I've tried running Crafty at my universitys multiprocessor machines, with poor >>results. Using 4 processors was kind of ok, but not great (~750 knps), but using >>many more processors (16, 24, etc.) just made it slower. How crummy is that. >> >>/David > >Are you sure? Sparc processors usually scale very well. > >If it really became worse I'd suspect a problem with Crafty. No.. it is a problem with memory bandwidth. The sparc is too slow and the crossbar is even slower... If you don't run out of the cache, you get killed on memory bandwidth with large numbers of processors... > >OK, a silly question: did you remember to recompile Crafty so that it really >could use all those processors? That is a good point, with -DCPUS=128 or something similar... Otherwise most processors will be spinning and eating bandwidth for nothing... > >pete
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.