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Subject: Re: Hashtable problems

Author: scott farrell

Date: 07:24:31 09/11/02

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On September 11, 2002 at 08:09:52, Steffen Basting wrote:
Hi,

A few suggestions- your q-nodes are way too high in comparison to your nodes. I
get about 6%-15% of totals nodes, you have the opposite. I fixed this by
"stand=pat" code in my qsearch.

What is your code for hashtable?
What are you storing?
What is you condition to return a value from the hashtable?

Scott

>Hello!
>I've got some problems with my hashtable...
>Here's the output of the starting position:
>
>time depth      nodes           value   principal variation
>===============================================================================
>0       1       24              -10     g1f3
>0       2       66              -11     g1f3  -
>0       2       130             -28     g1f3 g8f6
>0       3       134             -27     g1f3  +
>0       3       719             -4      g1f3 g8f6 b1c3
>0       4       722             -3      g1f3  +
>0       4       895             -5      g1f3  -
>0       4       4027            -22     g1f3 g8f6 b1c3 b8c6
>0       5       6229            -21     g1f3  +
>0       5       18882           -7      g1f3 g8f6 b1c3 b8c6 e2e4
>1       6       22129           -8      g1f3  -
>1       6       85215           -21     d2d4 g8f6 g1f3 d7d5 b1c3 b8c6
>2       7       198553          -20     d2d4  +
>3       7       518883          -7      e2e4 b8c6 g1f3 g8f6 b1c3 d7d5 f1d3
>8       8       600111          -8      e2e4  -
>9       8       4135936         -14     g1f3 g8f6 b1c3 b8c6 d2d4 e7e6 c1g5 d7d5
>56      9       7292704         -13     g1f3  +
>705603 nodes, 101 seconds: 71497 nodes/sec
>q-nodes: 6587101        evals: 6587101
>hash hits: 168 hash alpha cut: 106 hash beta cut: 0
>value: -13
>my move: g1f3
>
>And another one from the following position:
>[D]8/5ppp/8/5PPP/8/k7/8/K7 w - - 0 1
>
>time depth      nodes           value   principal variation
>===============================================================================
>1       9       57531           20      a1b1  -
>1       9       107320          19      a1b1 a3b4 h5h6 g7h6 g5h6 f7f6 b1c1 b4b3
>c1b1
>2       10      132473          20      a1b1  +
>2       10      225075          24      a1b1 a3b4 b1c2 b4c5 h5h6 g7h6 g5h6 f7f6
>c2c1 c5c4
>2       11      258326          25      a1b1  +
>3       11      531269          688     g5g6 h7g6 f5f6 g7f6 h5h6 f6f5 h6h7 f5f4
>h7h8Q f7f5 a1b1
>5       12      569305          687     g5g6  -
>5       12      2047277         689     a1b2 a3b2 b2a3 a3a2 a2a3 b2a1 a1a2 a2b2
>b2a2 b3b2 b1b2 b2b1 b1b2   +
>16      12      2898223         695     g5g6 h7g6 f5f6 g7f6 h5h6 f6f5 h6h7 f5f4
>h7h8Q f7f6 h8a8 a3b4 b1b2
>22      13      3236424         696     g5g6  +
>25      13      3988875         698     g5g6 h7g6 f5f6 g7f6 h5h6 f6f5 h6h7 a3b4
>h7h8Q f7f6 h8g8 g6g5 g8e8
>1138587 nodes, 31 seconds: 124652 nodes/sec
>q-nodes: 2850288        evals: 2850288
>hash hits: 424 hash alpha cut: 318 hash beta cut: 0
>value: 698
>my move: g5g6
>
>Something is wrong - I simply don't find the mistake...Have a look at the line
>of depth 12 for example - if the search had stopped at this point, my program
>would had lost in a won position with a positive score.
>Any suggestions - what might be the mistake?
>
>Thanks, Steffen



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