Author: Antonio Dieguez
Date: 08:33:51 09/25/01
Go up one level in this thread
>Note that I don't sign on to the theory that more ram increases the probability >of a collision. Try it yourself, then. With different hashtable sizes. this is what I got in the initial position, with 16 bits total. With replacing scheme always replace. with 128 entries: [9] 978059 nodes, illegal moves=2416 with 256: [9] 909888 nodes, illegal moves=3113 512: [9] 944380 nodes, illegal moves=5450 1024: [9] 847469 nodes, illegal moves=9062 2048: [9] 915317 nodes, illegal moves=15875 4096: [9] 1183890 nodes, illegal moves=38123 I think it will be obviously the same trying others positions too. > The probability of a collision is 1 / 2^64 for a normal >position. This means for a table that holds 2^64 entries in a 2^64 signature >space. Smaller RAM improves that by overwriting/replacing entires before they >can collide. But the base 1/2^64 is good enough for me. That is a very tiny >number... If you don't like one of my conditions, try it yourself with that corrected. But using 2^somethings as a hash capacity. >Since we will never see memories that large, the probabilities are going to be >good enough for a long time, assuming that 1 collision every few billion nodes >is acceptable... So far that seems to be ok... yes, okey but we are not discusing 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.