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Up Topic The Rybka Lounge / Computer Chess / Chessbase 9 and hash
- - By tigershark (**) Date 2012-06-24 16:35
Hi

I have chessbase 9 and allocate 2gig to hash (I have 8gig of memory).

If I leave the computer on infinite analysis and it gets to a position say 25 deep; and then I play the recommended move, the computer starts back at depth 19 again and still takes a while to get to depth 25.  Is something wrong here please? Shouldn't the computer just carry on at depth 25 if I have played the recommended move?

If not, what's the point of hash!!?
Parent - - By Master Om (Bronze) Date 2012-06-24 16:55
What engine you  use ?
Try using Critter 1.6 with learning on.
Parent - - By tigershark (**) Date 2012-06-24 16:59
houdini 1.5
Parent - - By tigershark (**) Date 2012-06-24 17:01
the engine paramaters (inside chessbase) don't seem to have a learning option for critter 1.6?
Parent - - By Permanent Brain (*****) Date 2012-06-24 17:07
It's called "Use Session File". That is the permanent learning file of Critter.
Parent - By tigershark (**) Date 2012-06-24 17:22
thanks. Reinstalled critter 1.6 in chessbase and changed to include that parameter
Parent - - By Permanent Brain (*****) Date 2012-06-24 17:06

> Is something wrong here please?


No, I consider this to be entirely normal. Also, note that 19 is a HUGE depth to start with, immediatly after a move was entered.

P.S. If it's really Houdini 1.5 only, you can download the most recent free version 1.5a.
Parent - - By tigershark (**) Date 2012-06-24 17:07
thanks - it is 1.5a

Glad to know it's normal. I just don't understand hash.

i.e. if I have searched to depth 25. and then play the recommended move; shouldn't the analysis carry on at depth 25? what am I misunderstanding?
Parent - - By Permanent Brain (*****) Date 2012-06-24 17:10
This is a question a chess programmer should answer.

My best guess is, that even after the expected move is entered, the engine creates a wider tree than in the previous search.
Parent - - By tigershark (**) Date 2012-06-24 17:21
That makes sense if correct.

I wonder how much difference in speed there is between a 2 gig hash and say a 512mb hash? Is it material or could I free up some of my computer resources for little 'chess' performance loss?
Parent - - By Permanent Brain (*****) Date 2012-06-24 18:27
Not a very big speed difference, but you can compare that easily by having the engine analysing some typical positions and note the time to a certain depth, each. First with 512 MB and then, after closing and restarting the program, with 2 GB (or with any other pair of hash table sizes as long as they fit into your free RAM memory).

The gain from hash learning(*) and from permanent learning for analyses, is certainly much bigger than from simply changing hash from 512 MB to 2 GB.

*) search this and other computer chess fora for "hash learning", "backwards analysis" etc. if you are new to this interactive analysis technique
Parent - By tigershark (**) Date 2012-06-24 18:36
Thanks. Will research it. Will have to check if I need to alter settings in houdini to get hash learning working

Thanks for help

I'm not a computer chess person really; I simply use the engine to help analyse openings/my games
Up Topic The Rybka Lounge / Computer Chess / Chessbase 9 and hash

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