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Subject: Re: Quiescent v Normal Node Ratio

Author: Peter McKenzie

Date: 13:19:22 10/06/99

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On October 06, 1999 at 13:50:48, Scott Gasch wrote:

>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

This looks a little weird, a 3 ply variation at depth 2.  I can't see why you'd
want to extend after any of those moves, so maybe something is broken.

>3       29      0       976     g8f6 g1f3 b8c6
>4       18      0       3905    d7d5 b1c3 d5d4 c3e4 c8f5

A 5 ply variation at depth 4.  Maybe you are doing a threat extension after
d5d4?

>5       4       100     22049   g8f6 g1f3 b8a6
>6       21      500     111840  g8f6 g1f3 b7b6 g2g3 c8b7 f1g2 b7f3

Your branching factor looks a little unhealthy.

>
>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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