Author: Vincent Diepeveen
Date: 06:02:37 12/07/99
Go up one level in this thread
On December 06, 1999 at 15:33:03, Robert Hyatt wrote: >On December 06, 1999 at 13:00:56, Georg v. Zimmermann wrote: > >>>A thousand fold increase would be >>>what, an additional 6 ply search in the same time? >> >>Lets do some math. 40^x = 1000, 40log 1000 = x, x = 10log1000 / 10log40, x = >>3/10log40 = 3 / 1.5 = 1.9 >> >>I think it gets you "1.9 ply" deeper if you do brute force. Now we need someone >>to tell us how much that is if you add HT and other modern wunder drugs. >>But I would be very very suprised if you'd reach +6ply. > > >DB has an effective branching factor of roughly 6, about the same as Cray >Blitz, which didn't use R=2/recursive null move. Log6(1000) is at most 4, >so it would get about 4 plies deeper. Certainly nothing to sneeze at... see different post of me. DB may be happy with a b.f. from 10.33 >But then again, this math is really wrong, because for each cpu, DB used >16 chess processors. Each chess processor could search about 2.4M nodes per >second (they used almost 500 for DB2 the last match). With one million >processors, they would then have 16M chess processors, and would be >searching about 40,000,000,000,000 nodes per second. At about 1 billion >(max) for DB2, this would be 40,000 times faster. and log6(40000) is 6, >so they could hit about 6 plies deeper. Very dangerous box... the more processors the smaller the speedup. just attaching all processors to the search might take a few minutes. Note that HSU writes that they got very close to 1 billion positions a second but never hit the magic 1 billion positions a second number. Vincent
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.