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Subject: Re: Quiescent v Normal Node Ratio

Author: Scott Gasch

Date: 10:50:48 10/06/99

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On October 06, 1999 at 09:41:00, Steve Maughan wrote:

>What is the 'best' or lowest ratio of quiescent nodes to normal nodes.  I am
>currently analysing about 5:1 ie the vast majority of my time is being spent in
>QSearch and I was wondering what is 'normal'.
>
>For the aviodance of doubt, I have two search procedures AlphaBeta and QSearch.
>The ratio that I'm interested in is the ratio of nodes processed by QSearch
>against those processed by AlphaBeta.


Hi Steve,

I too have this problem -- I see about 4x more qnodes than tree nodes.  I am
doing winning captures only (with a SEE) and a futility check (delta pruning ala
crafty) in the qeval routine.  I am not sure what I could be doing wrong unless
my move ordering is messed up somehow.  My move generator returns:

1) PV nodes
2) winning captures
3) losing captures
4) killers
5) the rest ordered based on history table

I appreciate any advice... here are some sample search stats after 1. a2a3
searching to 6 ply:

Thinking.
1       39      0       55      g8f6
2       4       0       752     g7g6 g1f3 g8f6
3       29      0       976     g8f6 g1f3 b8c6
4       18      0       3905    d7d5 b1c3 d5d4 c3e4 c8f5
5       4       100     22049   g8f6 g1f3 b8a6
6       21      500     111840  g8f6 g1f3 b7b6 g2g3 c8b7 f1g2 b7f3

move g8f6
------------------------------------------------------------------

search stats:

  111842 search nodes (111840 internal, 2 leaf) and 453383 qeval nodes.
  1221 qeval futility cuts, 1263 search futility cuts, and 220881 lazy evals.
  processed 82076 line extensions.
  79357 null move successes, 29216 failures, 73.09% null move efficiency.
  searched for 5.24 sec at a rate of 107951 nodes/sec.

hash stats:

  main hash: 24217 adds, 1637 (14) hits, 110203 misses, 1.46% efficiency.
  pawn hash: 153812 hits, 78691 misses, 66.15% efficiency.

misc. stats:

  aspiration: 6 successes, 0 failures, 100.00% efficiency.

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