Author: John Merlino
Date: 09:18:33 04/10/01
Go up one level in this thread
On April 10, 2001 at 01:50:29, Paul Doire wrote: >Hardware:541Mhz celeron 128 mb ram win98se >G/5, All engines have 32 MB Hash except CM default. >All engine settings found here at this site > >Results: W D L Games Score >CM KKND 32H 10 8 6 24 14.0 >Chessmaster(default) 7 12 5 24 13.0 >CM 32H 7 9 8 24 11.5 >CM DEEP 32H(Kostick bk)6 10 8 24 11.0 >CM 8777 32H 5 11 8 24 10.5 > >CM KKND is clearly stronger in this sampling. >I have also played many offhand games with CM KKND against >Gambit Tiger 2...G/5 same pc ponder on, and CM KKND appears >to win 60-70% of the time! This (in some way) goes to prove one VERY IMPORTANT point that Johan and I have stated time and time again. A 32MB hash table is 31MB too many for a G/5 game! Johan uses the general rule of thumb of 1 byte per average position searched per move. Since, on the average, CM8000 searches between 50K and 100K moves per second (depending on processor speed -- your Celeron is going to be closer to 50K), this means that, unless the engine is going to have more than 10 seconds average PER MOVE, there is NO REASON for anything more than a 1MB hash table. Johan believes that, unless you're on a very fast processor, a 1MB hash table is fine for everything up to G/10. The reason for the point that I'm making is that, with each new move, CM clears out its hash table. A 32MB hash table takes approximately 1/2 second to clear. In a G/5 game that goes 80 moves, this means that the engine has lost 40 seconds, compared to a personality with an appropriate 1MB hash table. This explains why the default personality had a better score than the 32MB version of the default personality. HOWEVER, the next version of the patch (due out very soon), is going to fix this problem to some degree. Johan has made the clearing of the hash table almost "instant", meaning that using a too large hash table in a blitz game will no longer be a detriment. As for your stating that KKND is "clearly stronger", I see absolutely no evidence of that -- 1 point in a 24 game tournament? This is, statistically, meaningless. jm
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.