Author: Robert Hyatt
Date: 08:08:57 05/01/04
Go up one level in this thread
On May 01, 2004 at 11:07:15, Robert Hyatt wrote: >On May 01, 2004 at 06:21:49, Tom Kerrigan wrote: > >>I got access to a quad proc computer this evening and timed how long it took to >>search the BK positions to 10 ply, varying the # of threads. Here's the result. >> >>threads time(s) NPS(k) time NPS search efficiency >>1 943 206 - - 100% >>2 585 401 1.61x (as fast) 1.94x 82% >>3 414 569 2.27x 2.76x 82% >>4 365 742 2.58x 3.60x 71% >> >>I was wondering how this compares to other programs. My program uses a simple >>implementation of YBW, which I found to perform significantly better than >>ABDADA. (The latter seems to perform fine until you turn on null move.) >> >>I recall most algorithms in the ICCA Journal claiming excellent scaling for >>4-way, usually over 3x IIRC. So I'm a little disappointed by 2.58x but I wonder >>how other people measure speedups. Is it with null move on? Also, the set of >>positions makes a huge difference. On 11 of the BK positions I get > 3x but the >>overall average is dragged down by a few < 2x positions that take a long time to >>search. >> >>-Tom > > >If you can post the positions, and the exact experimental set-up (ie you said >search to fixed depth) I can run the same test... OK. I think I mis-read the first time around. Seems like you searched all 24 BK positions to sd=10? I can run that but depth=10 is going to run _very_ quickly. sd=12 would be a better test...
This page took 0.04 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.