Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: UltraSPARC III sucks

Author: Dann Corbit

Date: 13:01:49 01/02/02

Go up one level in this thread


On January 02, 2002 at 15:54:41, David Rasmussen wrote:

>On January 02, 2002 at 15:40:08, Dann Corbit 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.
>>
>>Did you do the compile with 96 processors enabled?  It won't do that by default.
>>I am pretty sure you need to change the define for CPUs like this:
>>#define CPUS=96
>>
>>Look at this in chess.h:
>>
>>#if !defined(CPUS)
>>#  define CPUS 1
>>#endif
>>
>>I am guessing you will see (96/4) * 0.7 * 750K = ~12M NPS or so.
>
>I changed -DCPUS=4 to -DCPUS=16 in Makefile and put mt=16 in .craftyrc

Hmmmm.....
Does Ultra Sparc III have an interlocked exchange?  I suspect that the makefile
is defaulting to mutexes or something really icky like that.




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.