Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Hash Table

Author: Stuart Cracraft

Date: 16:11:38 01/19/98

Go up one level in this thread


On January 19, 1998 at 17:37:34, Robert Hyatt wrote:

>On January 19, 1998 at 17:09:00, Stuart Cracraft wrote:
>
>>What is the typical hash table successful percentage retrieve value?
>>
>>I'm looking for this number for at least one other program for a
>>typical search or group of searches:
>>
>>	found-in-hashtable * 100
>>	------------------------
>>      total attempts to probe hashtable
>>
>>--Stuart
>
>
>Depends on what you are counting, and the position you are searching.
>
>If you are simply counting positions where the hash signature matches
>what is in the table, you should get 25% and higher.  If you are
>counting
>positions where the hash table hit actually stops the search early due
>to
>a fail high/low or exact score match, this should be around 10% and get
>better as depth increases.

I assume your 25% case reflects that the called-depth >= stored-depth
for the store-entry case and stored-depth < called-depth for the
retrieve-entry
case where stored-depth is the depth currently in the hash table and
called-depth is the depth supplied to the store-entry/retrieve-entry
routines.

--Stuart



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.