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Host Duration Avg Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo

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ID Host Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo CLI PGN


Commit ID d71adc5bd979fd42ff9bbb3d2257e188aac86be9
Author Leonid Pechenik
Date 2018-02-09 09:41:32 UTC
Retire "Extra thinking before accepting draw PVs" This patch simplifies the time management code, removing the extra thinking time for moves with draw PV and increasing thinking time for all moves proportionally by around 4%. Last time when the time management was carefully tuned was 1.5-2 years ago. As new patches were getting added, time management was drifting out of optimum. This happens because when search becomes more precise pv and score are becoming more stable, there are less fail lows, best move is picked earlier and there are less best move changes. All this factors are entering in time management, and average time per move is decreasing with more and more good patches. For individual patches such effect is small (except some) and may be up or down, but when there are many of them, effect is more substantial. The same way benchmark with more and more patches is slowly drifting down on average. So my understanding that back in October adding more think time for draw PV showed positive Elo because time management was not well tuned, there was more time available, and think_hard patch applied this additional time to moves with draw PV, while just retuning back to optimum would recover Elo anyway. It is possible that absence of contempt also helped, as SF9 is showing less 0.0 scores than the October version. Anyway, to me it seems that proper place to deal with draw PV is search, and contempt sounds as much better solution. In time management there is little additional elo, and if some code is not helping like removed here, it is better to discard it. It is simpler to find genuine improvement if code is clean. • Passed STC: LLR: 2.95 (-2.94,2.94) [-3.00,1.00] Total: 20487 W: 4558 L: 4434 D: 11495 • Passed LTC: LLR: 2.96 (-2.94,2.94) [-3.00,1.00] Total: 41960 W: 7145 L: 7058 D: 27757 • Passed an additional non-regression [-5..0] test at the time control of 60sec for the game (sudden death) with disabled draw adjudication: LLR: 2.95 (-2.94,2.94) [-5.00,0.00] Total: 8438 W: 1675 L: 1586 D: 5177 • Passed an additional non-regression [-5..0] test at the time control of 1sec+1sec per move with disabled draw adjudication: LLR: 2.97 (-2.94,2.94) [-5.00,0.00] Total: 27664 W: 5575 L: 5574 D: 16515 This is a functional change for the time management code. Bench: 4983414
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