Commit Graph
2807 Commits
Author SHA1 Message Date
Michael ChalyandDisservin 79261bec59 Simplify away reductions adjustment for multithreaded search
Seem to no longer bring measurable benefit.

Passed STC SMP simplification:
https://tests.stockfishchess.org/tests/view/6753561a86d5ee47d954151f
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 38000 W: 9864 L: 9656 D: 18480
Ptnml(0-2): 53, 4177, 10320, 4409, 41

Passed LTC SMP simplification:
https://tests.stockfishchess.org/tests/view/6753d75f86d5ee47d9541669
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 258674 W: 66314 L: 66335 D: 126025
Ptnml(0-2): 77, 26957, 75303, 26910, 90

Passed 16 threads LTC simplification:
https://tests.stockfishchess.org/tests/view/675a066286d5ee47d9542296
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 221804 W: 56950 L: 56936 D: 107918
Ptnml(0-2): 34, 21491, 67839, 21503, 35

closes https://github.com/official-stockfish/Stockfish/pull/5729

Bench: 1294909
2024-12-22 15:28:15 +01:00
Disservin 4bc2a24245 Workaround for clang-format bug
closes https://github.com/official-stockfish/Stockfish/pull/5728

No functional change
2024-12-22 15:27:40 +01:00
Shawn XuandDisservin e7e78aa09e Adjust LMR with correction history
A positive constant increase in base reduction is applied to counter the
decrease in average reduction from this tweak.

Passed STC:
LLR: 2.98 (-2.94,2.94) <0.00,2.00>
Total: 109216 W: 28415 L: 27989 D: 52812
Ptnml(0-2): 310, 12848, 27911, 13184, 355
https://tests.stockfishchess.org/tests/view/6760bb0e86d5ee47d9542f26

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 66918 W: 17073 L: 16694 D: 33151
Ptnml(0-2): 33, 7175, 18666, 7550, 35
https://tests.stockfishchess.org/tests/view/6761e10f86d5ee47d95431fa

closes https://github.com/official-stockfish/Stockfish/pull/5727

Bench: 1294909
2024-12-22 15:26:39 +01:00
FauziAkramandDisservin a04b07265f Make reductionScale smoother
Making the second part of the formula smoother, changing it to a linear
function, increasing steadily as reductionScale increases and at the
same time, it should be a little bit simpler, therefore the
simplification bounds.

Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 83040 W: 21493 L: 21322 D: 40225
Ptnml(0-2): 252, 9848, 21209, 9899, 312
https://tests.stockfishchess.org/tests/view/6762145486d5ee47d9543242

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 230124 W: 58485 L: 58478 D: 113161
Ptnml(0-2): 175, 25620, 63484, 25589, 194
https://tests.stockfishchess.org/tests/view/6762d4ef86d5ee47d9543367

closes https://github.com/official-stockfish/Stockfish/pull/5725

Bench: 1204658
2024-12-22 15:24:09 +01:00
Disservin 2dc47e4345 Cleanup Evaluate Calls
Makes code a bit easier to read as well.

closes https://github.com/official-stockfish/Stockfish/pull/5722

No functional change
2024-12-22 15:19:53 +01:00
Daniel MonroeandDisservin ba145332c9 Remove time reduction for recaptures
Passed simplification STC
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 54016 W: 14098 L: 13902 D: 26016
Ptnml(0-2): 165, 5797, 14919, 5931, 196
https://tests.stockfishchess.org/tests/view/6758a90486d5ee47d954201e

Passed simplification LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 296940 W: 75631 L: 75689 D: 145620
Ptnml(0-2): 145, 28928, 90384, 28866, 147
https://tests.stockfishchess.org/tests/view/6758df7a86d5ee47d9542091

closes https://github.com/official-stockfish/Stockfish/pull/5719

Bench: 1148169
2024-12-22 15:17:55 +01:00
Shawn XuandDisservin e770b55f7f Remove Extraneous Parenthesis
No longer needed after
https://github.com/official-stockfish/Stockfish/pull/5667.

closes https://github.com/official-stockfish/Stockfish/pull/5717

No functional change
2024-12-22 15:17:33 +01:00
Shawn XuandDisservin b822fdf2f2 Tune histories
Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 268736 W: 70080 L: 69421 D: 129235
Ptnml(0-2): 831, 31795, 68460, 32448, 834
https://tests.stockfishchess.org/tests/view/6750778886d5ee47d9540e7c

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 505356 W: 129145 L: 127868 D: 248343
Ptnml(0-2): 307, 54901, 140959, 56230, 281
https://tests.stockfishchess.org/tests/view/675367de86d5ee47d9541536

closes https://github.com/official-stockfish/Stockfish/pull/5712

Bench: 1148169
2024-12-22 15:14:22 +01:00
Nonlinear2andGitHub cf10644d6e Fix duplicate code (#5711)
closes https://github.com/official-stockfish/Stockfish/pull/5711

No functional change
2024-12-08 22:24:29 +01:00
Michael ChalyandDisservin afaf3a0f2a Refine statscore for captures
Continuation of previous attempts there.
Now instead of using capture history with a static offset also add the
value of the captured piece in the same way at it is used in movepicker.

Passed STC:
https://tests.stockfishchess.org/tests/view/674aa3d386d5ee47d95404aa
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 116480 W: 30433 L: 29999 D: 56048
Ptnml(0-2): 361, 13720, 29662, 14118, 379

Passed LTC:
https://tests.stockfishchess.org/tests/view/674c4b2d86d5ee47d954073f
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 133542 W: 34365 L: 33847 D: 65330
Ptnml(0-2): 78, 14585, 36934, 15089, 85

closes https://github.com/official-stockfish/Stockfish/pull/5706

Bench: 934447
2024-12-08 19:57:59 +01:00
Shawn XuandDisservin 6a8478c6ad Simplify Prior Capture Countermove Bonus
Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 184032 W: 47626 L: 47568 D: 88838
Ptnml(0-2): 590, 21808, 47238, 21714, 666
https://tests.stockfishchess.org/tests/view/67412c7686d5ee47d953f743

Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 169218 W: 43395 L: 43323 D: 82500
Ptnml(0-2): 302, 18567, 46791, 18655, 294
https://tests.stockfishchess.org/tests/view/6743b7e086d5ee47d953f9a6

closes https://github.com/official-stockfish/Stockfish/pull/5701

Bench: 1130692
2024-12-08 19:55:10 +01:00
pb00067andDisservin 713000c517 Same weight for black and white nonPawnCorrection history
Since we don't have color dependent parameters in NNUE eval, it also has
no sense IMO to have color dependent parameters in correction histories.

Ideally a fixed depth search on a single thread should be determistic,
so delivering the same result (move) if we just flip colors on the
board.

Patch replaces 2 parameters (122 and 185) with just one value 154 (= the avg of the two).

Passed STC-non regression
https://tests.stockfishchess.org/tests/view/6740a63286d5ee47d953f656
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 122336 W: 31499 L: 31372 D: 59465
Ptnml(0-2): 336, 14535, 31301, 14658, 338

Passed LTC-non regression
https://tests.stockfishchess.org/tests/view/67419bae86d5ee47d953f7b6
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 101400 W: 25870 L: 25731 D: 49799
Ptnml(0-2): 78, 11109, 28166, 11290, 57

closes https://github.com/official-stockfish/Stockfish/pull/5698

Bench: 1215483
2024-12-08 19:52:16 +01:00
FauziAkramandDisservin d5a36a3c92 Simplify probCutBeta formula
After recent changes to the improving definition, seems like there is no
need anymore to keep opponentWorsening in the probCutBeta formula.

Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 214272 W: 55566 L: 55541 D: 103165
Ptnml(0-2): 620, 25540, 54817, 25513, 646
https://tests.stockfishchess.org/tests/view/6735243d86d5ee47d953eaea

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 126708 W: 32329 L: 32216 D: 62163
Ptnml(0-2): 68, 13986, 35123, 14119, 58
https://tests.stockfishchess.org/tests/view/67393cf686d5ee47d953ef99

closes https://github.com/official-stockfish/Stockfish/pull/5697

Bench: 983067
2024-12-08 19:49:01 +01:00
Nonlinear2andDisservin da82942b54 Add functions to check for decisive scores
Thanks to peregrineshahin and robbyrobbyrob for their suggestions.

closes https://github.com/official-stockfish/Stockfish/pull/5696

No functional change
2024-12-08 19:48:49 +01:00
Nonlinear2andDisservin 57e06be71f Add functions to check for decisive scores
Thanks to peregrineshahin and robbyrobbyrob for their suggestions.

closes https://github.com/official-stockfish/Stockfish/pull/5696

No functional change
2024-12-08 19:47:02 +01:00
Daniel MonroeandDisservin 70bb317afe Bonus for a prior capture that causes a fail low.
This tweak adds a bonus equal to twice the stat_bonus for the current depth for a prior capture that caused a fail high, similar to the prior countermove bonus we currently have.

Passed STC
https://tests.stockfishchess.org/tests/view/673bc14b86d5ee47d953f1f2
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 105824 W: 27538 L: 27118 D: 51168
Ptnml(0-2): 358, 12370, 27024, 12814, 346

Passed LTC
https://tests.stockfishchess.org/tests/view/673ccbff86d5ee47d953f2d9
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 134502 W: 34340 L: 33820 D: 66342
Ptnml(0-2): 102, 14634, 37229, 15214, 72

closes https://github.com/official-stockfish/Stockfish/pull/5695

Bench: 1107054
2024-12-08 19:46:07 +01:00
Daniel MonroeandDisservin fb6be17ad4 Simplify statscore at captures
Simplify statscores for captures, setting them to 0

A recent tweak of Vizvezdenec finds substantial elo gain from giving
captures a separate statscore, which is used mainly for reductions. The
idea is that the old combination of quiet histories was inappropriate
and that a value based on the capture history is more suitable. This
simplification sets the statscore for captures to 0, suggesting that the
elo gain came from rectifying the quiet history/capture mismatch.

Passed STC (against a slightly older version of Viz's patch)
https://tests.stockfishchess.org/tests/view/673ac6e286d5ee47d953f0ec
LR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 57312 W: 14872 L: 14672 D: 27768
Ptnml(0-2): 152, 6761, 14649, 6923, 171

Passed LTC (against Viz's newest patch)
https://tests.stockfishchess.org/tests/view/673cd00686d5ee47d953f2db
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 88236 W: 22510 L: 22358 D: 43368
Ptnml(0-2): 70, 9530, 24745, 9724, 49

closes https://github.com/official-stockfish/Stockfish/pull/5691

Bench: 959947
2024-11-22 23:34:15 +01:00
Shawn XuandDisservin 4fcd78ceb4 Simplify Probcut Bonus
Passed STC:
LLR: 2.99 (-2.94,2.94) <-1.75,0.25>
Total: 172288 W: 44656 L: 44580 D: 83052
Ptnml(0-2): 507, 20650, 43782, 20670, 535
https://tests.stockfishchess.org/tests/view/673b74f986d5ee47d953f1a3

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 94596 W: 24098 L: 23953 D: 46545
Ptnml(0-2): 57, 10322, 26393, 10471, 55
https://tests.stockfishchess.org/tests/view/673d191886d5ee47d953f337

closes https://github.com/official-stockfish/Stockfish/pull/5688

Bench: 1031022
2024-11-22 23:31:34 +01:00
Michael ChalyandDisservin cd3c13a883 Further tweak statscore for captures
Even lower offset.

Passed STC:
https://tests.stockfishchess.org/tests/view/673a66d786d5ee47d953f070
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 63776 W: 16570 L: 16216 D: 30990
Ptnml(0-2): 178, 7371, 16478, 7641, 220

Passed LTC:
https://tests.stockfishchess.org/tests/view/673b2e2a86d5ee47d953f14b
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 156960 W: 39999 L: 39435 D: 77526
Ptnml(0-2): 96, 16965, 43803, 17511, 105

closes https://github.com/official-stockfish/Stockfish/pull/5686

Bench: 867931
2024-11-22 23:29:37 +01:00
Guenther DemetzandDisservin d29c8bd5d4 Rewrite of 'Adjust correction history' condition
Current condition is convoluted and hard to understand because of
several negations. Also added 2 comments to make the concept behind the
condition better understandable.

closes https://github.com/official-stockfish/Stockfish/pull/5685

No functional change
2024-11-22 23:24:15 +01:00
FauziAkramandDisservin 0282edc0b0 Simplify bonus formula
Give full bonus instead of half.

Passed STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 23872 W: 6254 L: 6018 D: 11600
Ptnml(0-2): 80, 2691, 6152, 2939, 74
https://tests.stockfishchess.org/tests/view/673b709686d5ee47d953f19d

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 42894 W: 10924 L: 10725 D: 21245
Ptnml(0-2): 30, 4592, 12011, 4777, 37
https://tests.stockfishchess.org/tests/view/673bb50386d5ee47d953f1eb

closes https://github.com/official-stockfish/Stockfish/pull/5683

Bench: 836558
2024-11-22 23:23:42 +01:00
Michael ChalyandDisservin f129bf0de9 Tweak statscore for captures
Followup of a recent patch that separated statscore for captures and non-captures.
Lower value that we subtract from statscore if a move is a capture.

Passed STC:
https://tests.stockfishchess.org/tests/view/67385b6786d5ee47d953eeba
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 50592 W: 13223 L: 12888 D: 24481
Ptnml(0-2): 154, 5853, 12931, 6220, 138

Passed LTC:
https://tests.stockfishchess.org/tests/view/6739056e86d5ee47d953ef3f
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 23598 W: 6155 L: 5862 D: 11581
Ptnml(0-2): 16, 2466, 6543, 2757, 17

closes https://github.com/official-stockfish/Stockfish/pull/5682

Bench: 771180
2024-11-22 23:12:43 +01:00
Michael ChalyandDisservin 82b092ca48 Adjust statscore for captures
Instead of using quiet histories use capture history with a different
offset.

Passed STC:
https://tests.stockfishchess.org/tests/view/6731d5cc86d5ee47d953e719
LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 428896 W: 111160 L: 110269 D: 207467
Ptnml(0-2): 1220, 50296, 110534, 51169, 1229

Passed LTC:
https://tests.stockfishchess.org/tests/view/6733d9fd86d5ee47d953e962
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 105882 W: 26918 L: 26458 D: 52506
Ptnml(0-2): 66, 11430, 29482, 11904, 59

closes https://github.com/official-stockfish/Stockfish/pull/5679

Bench: 840721
2024-11-13 20:35:02 +01:00
Nonlinear2andDisservin 43e100ae06 Use cutnode as TT Cutoff Condition
At low enough depths, fail high with TT only when expected cutnode.

Passed STC:
https://tests.stockfishchess.org/tests/view/6726357b86d5ee47d953da8c
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 41184 W: 10873 L: 10551 D: 19760
Ptnml(0-2): 131, 4728, 10554, 5046, 133

Passed LTC:
https://tests.stockfishchess.org/tests/view/6727326a86d5ee47d953db30
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 270888 W: 69040 L: 68243 D: 133605
Ptnml(0-2): 180, 29385, 75485, 30246, 148

closes https://github.com/official-stockfish/Stockfish/pull/5670

Bench: 805776
2024-11-13 20:35:02 +01:00
Muzhen GamingandDisservin 3d084e9164 VVLTC Search Tune
A single tuning run of 190k games was conducted:
https://tests.stockfishchess.org/tests/view/670f3e3786d5ee47d953c554.

Passed VVLTC 1st sprt:
https://tests.stockfishchess.org/tests/view/672344dc86d5ee47d953d8c3
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 56768 W: 14615 L: 14323 D: 27830
Ptnml(0-2): 3, 5152, 17789, 5430, 10

Passed VVLTC 2nd sprt (rebased):
https://tests.stockfishchess.org/tests/view/6726d83786d5ee47d953db03
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 57884 W: 14885 L: 14554 D: 28445
Ptnml(0-2): 5, 5300, 17999, 5635, 3

closes https://github.com/official-stockfish/Stockfish/pull/5669

Bench: 920336
2024-11-13 20:34:53 +01:00
Shawn XuandDisservin cc5c67c564 Introduce Fractional LMR
Tuning Run (90k Games):
https://tests.stockfishchess.org/tests/view/67202b1c86d5ee47d953d442

Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 241024 W: 62616 L: 62001 D: 116407
Ptnml(0-2): 716, 28231, 62015, 28822, 728
https://tests.stockfishchess.org/tests/view/6725196786d5ee47d953d9f2

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 92532 W: 23678 L: 23246 D: 45608
Ptnml(0-2): 45, 9981, 25797, 10383, 60
https://tests.stockfishchess.org/tests/view/6727d3cb86d5ee47d953db9d

closes https://github.com/official-stockfish/Stockfish/pull/5667

Bench: 1066071
2024-11-13 20:12:47 +01:00
FauziAkramandDisservin 54cf226604 Revert VLTC regression from #5634
https://tests.stockfishchess.org/tests/view/671bf61b86d5ee47d953cf23

And thanks to @xu-shawn for suggesting running a VLTC regress test since
depth modifications affect scaling. Also, the LTC was showing a slight
regress after 680+k games  ~= -0.34 , for reference:
https://tests.stockfishchess.org/tests/view/67042b1f86d5ee47d953be7c

closes https://github.com/official-stockfish/Stockfish/pull/5663

Bench: 1307308
2024-11-13 20:09:13 +01:00
Michael ChalyandDisservin ecf5646f6e Refine definition of improving
This patch also allows improving flag to be true if static evaluation of
the position is good enough.

Passed STC:
https://tests.stockfishchess.org/tests/view/6720906086d5ee47d953d4d0
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 34816 W: 9172 L: 8858 D: 16786
Ptnml(0-2): 113, 3988, 8887, 4312, 108

Passed LTC:
https://tests.stockfishchess.org/tests/view/6721162686d5ee47d953d597
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 145374 W: 37118 L: 36574 D: 71682
Ptnml(0-2): 91, 15875, 40212, 16417, 92

closes https://github.com/official-stockfish/Stockfish/pull/5662

Bench: 1518856
2024-11-13 20:08:14 +01:00
Shawn XuandDisservin c2611efe5c Move history code to a separate header
Since no correction histories are ever used inside Movepick, and many
existing histories are closely integrated into search, it might be more
logical to separate them into their own header. PR based on #5650

closes https://github.com/official-stockfish/Stockfish/pull/5652

No functional change
2024-11-13 20:07:15 +01:00
MinetaSandDisservin 24c57793e1 Remove moveCountPruning in search.cpp
The definition of moveCountPruning may cause confusion by implying that
the variable is unconstrained. However, once it is set to true, it
should not be reset to false, otherwise it would break the internal
logic of MovePicker.

Several patches have overlooked this constraint. For example:
https://tests.stockfishchess.org/tests/view/671e7c0486d5ee47d953d226
https://tests.stockfishchess.org/tests/view/66a1de7b4ff211be9d4eccea

The implementation approach was suggested by Disservin.

Passed non-regression STC:
LLR: 3.02 (-2.94,2.94) <-1.75,0.25>
Total: 180672 W: 47072 L: 47006 D: 86594
Ptnml(0-2): 536, 19482, 50247, 19522, 549
https://tests.stockfishchess.org/tests/view/6720df6f86d5ee47d953d542

closes https://github.com/official-stockfish/Stockfish/pull/5661

No functional change
2024-10-31 10:08:34 +01:00
FauziAkramandDisservin 8681d3c2b3 Simplify Time Management Formula
Decreasing the number of operations
Passed STC:
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 38880 W: 10038 L: 9823 D: 19019
Ptnml(0-2): 92, 4334, 10395, 4505, 114
https://tests.stockfishchess.org/tests/view/67112bf586d5ee47d953c6be

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 242844 W: 61425 L: 61431 D: 119988
Ptnml(0-2): 145, 25175, 70797, 25151, 154
https://tests.stockfishchess.org/tests/view/6712387486d5ee47d953c737

closes https://github.com/official-stockfish/Stockfish/pull/5655

Bench: 1281912
2024-10-31 10:07:24 +01:00
Michael ChalyandDisservin 8ef403c786 Small cleanup for stats adjustments
After some simplifications bonuses and maluses are the same for quiet
and non-quiet moves so it makes no sense to use quietMoveBonus/Malus,
instead use just bonus/malus.

closes https://github.com/official-stockfish/Stockfish/pull/5649

No functional change
2024-10-31 09:26:00 +01:00
FauziAkramandDisservin 2ce47573b4 Remove -stat_malus(newDepth)
Passed STC:
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 92544 W: 23940 L: 23778 D: 44826
Ptnml(0-2): 286, 10936, 23638, 11154, 258
https://tests.stockfishchess.org/tests/view/670c3d6986d5ee47d953c30b

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 43164 W: 10986 L: 10786 D: 21392
Ptnml(0-2): 27, 4713, 11905, 4907, 30
https://tests.stockfishchess.org/tests/view/670eda3d86d5ee47d953c51d

closes https://github.com/official-stockfish/Stockfish/pull/5639

Bench: 1281912
2024-10-31 09:25:59 +01:00
FauziAkramandDisservin b325b2c348 Simplify bestValue formula
Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 45888 W: 12051 L: 11841 D: 21996
Ptnml(0-2): 123, 5356, 11807, 5504, 154
https://tests.stockfishchess.org/tests/view/670bb89086d5ee47d953c2d8

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 51336 W: 13021 L: 12830 D: 25485
Ptnml(0-2): 34, 5594, 14227, 5773, 40
https://tests.stockfishchess.org/tests/view/670c587f86d5ee47d953c31b

closes https://github.com/official-stockfish/Stockfish/pull/5637

Bench: 1192999
2024-10-31 09:25:59 +01:00
FauziAkramandDisservin 7f386d109e Remove material corrHist
Passed STC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 80832 W: 21150 L: 20975 D: 38707
Ptnml(0-2): 283, 9531, 20598, 9736, 268
https://tests.stockfishchess.org/tests/view/670302fe86d5ee47d953bd68

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 46008 W: 11621 L: 11423 D: 22964
Ptnml(0-2): 30, 5072, 12606, 5262, 34
https://tests.stockfishchess.org/tests/view/6704074686d5ee47d953be53

Passed LTC Rebased:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 95814 W: 24340 L: 24195 D: 47279
Ptnml(0-2): 71, 10497, 26602, 10690, 47
https://tests.stockfishchess.org/tests/view/670ae1ac86d5ee47d953c262

closes https://github.com/official-stockfish/Stockfish/pull/5636

Bench: 1119774
2024-10-31 09:25:56 +01:00
Taras VukandDisservin bf2a0d5392 Simplify internal iterative reductions
Passed STC:
LLR: 2.92 (-2.94,2.94) <-1.75,0.25>
Total: 138656 W: 36182 L: 36074 D: 66400
Ptnml(0-2): 523, 16422, 35310, 16570, 503
https://tests.stockfishchess.org/tests/view/6702beb386d5ee47d953bd41

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 680844 W: 172021 L: 172480 D: 336343
Ptnml(0-2): 492, 76259, 187419, 75720, 532
https://tests.stockfishchess.org/tests/view/67042b1f86d5ee47d953be7c

closes https://github.com/official-stockfish/Stockfish/pull/5634

Bench: 1169252
2024-10-31 09:13:35 +01:00
Michael ChalyandDisservin 9766db8139 Make low ply history size fixed
Size of low ply history should always be the same, so ensure it.

closes https://github.com/official-stockfish/Stockfish/pull/5630

No functional change
2024-10-12 16:40:55 +02:00
Nonlinear2andDisservin aaadbe0572 Introduce mean squared score for delta adjustments
This patch introduces the value `meanSquaredScore`, which makes the
initial delta sensitive to unstable iterative deepening scores.

Passed STC:
https://tests.stockfishchess.org/tests/view/66fed74286d5ee47d953bb42
LLR: 2.98 (-2.94,2.94) <0.00,2.00>
Total: 71104 W: 18635 L: 18262 D: 34207
Ptnml(0-2): 234, 8365, 17993, 8714, 246

Passed LTC:
https://tests.stockfishchess.org/tests/view/6700088e86d5ee47d953bbe9
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 212544 W: 54238 L: 53560 D: 104746
Ptnml(0-2): 120, 23093, 59172, 23763, 124

closes https://github.com/official-stockfish/Stockfish/pull/5627

Bench: 1395505
2024-10-12 16:40:37 +02:00
FauziAkramandDisservin 9a21e3e996 Simplify bestvalue formula
Passed STC:
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 163680 W: 42689 L: 42605 D: 78386
Ptnml(0-2): 619, 19555, 41386, 19683, 597
https://tests.stockfishchess.org/tests/view/66f9451386d5ee47d953b7d9

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 96498 W: 24582 L: 24438 D: 47478
Ptnml(0-2): 62, 10642, 26718, 10744, 83
https://tests.stockfishchess.org/tests/view/66fd765786d5ee47d953ba1c

closes https://github.com/official-stockfish/Stockfish/pull/5622

Bench: 1309815
2024-10-12 16:30:44 +02:00
mstemberaandDisservin 3348603770 Simplify previous #5608
https://github.com/official-stockfish/Stockfish/pull/5608

STC: https://tests.stockfishchess.org/tests/view/66fb1bab86d5ee47d953b8cc
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 25536 W: 6797 L: 6560 D: 12179
Ptnml(0-2): 93, 2953, 6460, 3148, 114

LTC https://tests.stockfishchess.org/tests/view/66fb690e86d5ee47d953b8eb
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 225114 W: 57200 L: 57188 D: 110726
Ptnml(0-2): 197, 25076, 61995, 25096, 193

closes https://github.com/official-stockfish/Stockfish/pull/5621

Bench: 1570076
2024-10-12 16:30:44 +02:00
Ömer Faruk TutkunandDisservin 6592b13d56 Introduce Continuation Correction History
Continuation correction history uses last 2 move to correct static eval.

ContCorrHist first introduced by @martinnovaak in
Motor(https://github.com/martinnovaak/motor/pull/162). Earlier ideas
using last move to correct eval is introduced by @MinusKelvin in
Ice4(https://github.com/MinusKelvin/ice4/commit/45daf7d9ea64ea4efaf0d2b4e99f53e12e08c838)

Passed STC:

LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 310144 W: 81267 L: 80538 D: 148339
Ptnml(0-2): 1160, 36607, 78834, 37286, 1185
https://tests.stockfishchess.org/tests/view/66f96cbc86d5ee47d953b7f7

Passed LTC:

LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 97470 W: 24892 L: 24447 D: 48131
Ptnml(0-2): 63, 10631, 26915, 11050, 76
https://tests.stockfishchess.org/tests/view/66fd59bc86d5ee47d953b9ea

closes https://github.com/official-stockfish/Stockfish/pull/5617

Bench: 1143382
2024-10-12 16:30:44 +02:00
Taras VukandJoost VandeVondele 81c1d31084 Decrease probCutBeta based on opponentWorsening
Passed STC:
LLR: 2.97 (-2.94,2.94) <0.00,2.00>
Total: 62112 W: 16305 L: 15947 D: 29860
Ptnml(0-2): 203, 7226, 15856, 7552, 219
https://tests.stockfishchess.org/tests/view/66f85fc986d5ee47d953b71e

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 129552 W: 33223 L: 32710 D: 63619
Ptnml(0-2): 94, 14250, 35573, 14767, 92
https://tests.stockfishchess.org/tests/view/66f93fef86d5ee47d953b7d2

closes https://github.com/official-stockfish/Stockfish/pull/5615

bench: 1511354
2024-10-04 08:35:08 +02:00
Michael ChalyandJoost VandeVondele 7ac745a736 Refactor root history into low ply history
This patch changes root history to low ply history - butterfly history for plies < 4.
Doubles weight of this history for root, latter plies have lesser effect.

Passed STC:
https://tests.stockfishchess.org/tests/view/66f77d2386d5ee47d953b65d
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 180992 W: 47362 L: 46830 D: 86800
Ptnml(0-2): 554, 21499, 45928, 21891, 624

Passed LTC:
https://tests.stockfishchess.org/tests/view/66fb557986d5ee47d953b8e5
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 42462 W: 11013 L: 10682 D: 20767
Ptnml(0-2): 33, 4518, 11795, 4855, 30

closes https://github.com/official-stockfish/Stockfish/pull/5614

Bench 1264335
2024-10-04 08:32:21 +02:00
Taras VukandJoost VandeVondele c85f802185 Tweak ttCapture reduction
More reduction at shallow depth for quiet moves when ttMove is a capture.

Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 365728 W: 95896 L: 95090 D: 174742
Ptnml(0-2): 1283, 43133, 93262, 43867, 1319
https://tests.stockfishchess.org/tests/view/66edd35986d5ee47d953b0d5

Passed LTC:
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 200526 W: 51197 L: 50540 D: 98789
Ptnml(0-2): 119, 21952, 55462, 22613, 117
https://tests.stockfishchess.org/tests/view/66f405dc86d5ee47d953b460

closes https://github.com/official-stockfish/Stockfish/pull/5610

bench: 1269487
2024-10-01 20:59:17 +02:00
Shawn XuandJoost VandeVondele d6043970bd Make Correction History Size Uniform
Passed Non-regression STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 207232 W: 53834 L: 53802 D: 99596
Ptnml(0-2): 695, 24486, 53200, 24562, 673
https://tests.stockfishchess.org/tests/view/66e9f5a886d5ee47d953ada1

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 99120 W: 25264 L: 25123 D: 48733
Ptnml(0-2): 66, 10803, 27675, 10956, 60
https://tests.stockfishchess.org/tests/view/66ed7ebc86d5ee47d953b056

Passed Non-regression LTC vs #5606:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 208950 W: 53049 L: 53019 D: 102882
Ptnml(0-2): 111, 23232, 57760, 23260, 112
https://tests.stockfishchess.org/tests/view/66f1843886d5ee47d953b2f2

closes https://github.com/official-stockfish/Stockfish/pull/5609

bench 1575189
2024-09-28 18:01:31 +02:00
peregrineshahinandJoost VandeVondele 56444ce1f7 Push expected cutting late moves up in the move ordering.
since the passing of the LMR verification is coming from a relatively late move
this means we have wasted some time trying/picking other moves, and it would
make sense to push it up in the move ordering for future positions not to be as
late.

Passed STC:
https://tests.stockfishchess.org/tests/view/66f0f69186d5ee47d953b2aa
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 34144 W: 9024 L: 8709 D: 16411
Ptnml(0-2): 137, 3875, 8732, 4192, 136

Passed LTC:
https://tests.stockfishchess.org/tests/view/66f1d84a86d5ee47d953b325
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 62808 W: 16054 L: 15684 D: 31070
Ptnml(0-2): 24, 6725, 17555, 7057, 43

closes https://github.com/official-stockfish/Stockfish/pull/5608

bench: 1452807
2024-09-28 18:01:31 +02:00
Nonlinear2andJoost VandeVondele aff1f67997 simplify see pruning in qsearch
passed non-regression STC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 34880 W: 9193 L: 8968 D: 16719
Ptnml(0-2): 103, 4047, 8935, 4232, 123
https://tests.stockfishchess.org/tests/view/66ee83bd86d5ee47d953b15b

passed non-regression LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 69126 W: 17529 L: 17357 D: 34240
Ptnml(0-2): 41, 7507, 19285, 7699, 31
https://tests.stockfishchess.org/tests/view/66ef3e0386d5ee47d953b1d3

closes https://github.com/official-stockfish/Stockfish/pull/5607

Bench: 1339840
2024-09-28 17:22:33 +02:00
Joost VandeVondele ae420e735f Tweak Correction histories
tune parameters some more, adjust scores updated for each history

passed STC:
https://tests.stockfishchess.org/tests/view/66ea569186d5ee47d953ae48
LLR: 2.92 (-2.94,2.94) <0.00,2.00>
Total: 36288 W: 9660 L: 9344 D: 17284
Ptnml(0-2): 110, 4207, 9220, 4471, 136

passed LTC:
https://tests.stockfishchess.org/tests/view/66ea9b4e86d5ee47d953ae6f
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 241446 W: 61748 L: 61010 D: 118688
Ptnml(0-2): 173, 26211, 67202, 26979, 158

closes https://github.com/official-stockfish/Stockfish/pull/5606

Bench: 1677953
2024-09-28 17:17:44 +02:00
Shawn XuandDisservin 60351b9df9 Introduce Various Correction histories
This patch introduces three additional correction histories, namely,
Major Piece Correction History, Minor Piece Correction History, and
Non-Pawn Correction History.

Introduced by @mcthouacbb in Sirius
(https://github.com/mcthouacbb/Sirius) chess engine. The Major Piece
Correction History is indexed by side-to-move and the Zobrist key
representing the position of the King, Rook, and Queen of both sides.
Likewise, the Minor Piece Correction History is indexed by side-to-move
and the Zobrist key representing the position of the King, Knight, and
Bishop of both sides.

Also See:
https://github.com/mcthouacbb/Sirius/commit/97b85bbaac88ff5a0f63e28776027dd3de77164e
https://github.com/mcthouacbb/Sirius/commit/3099cdef2f13e29805654b5f8153e6ecd5853195

Introduced by @zzzzz151 in Starzix (https://github.com/zzzzz151/Starzix)
chess engine. Non-Pawn correction history consists of side-to-move, side
of Zobrist key, and a Zobrist key representing of the position of all
non-pawn pieces of **one side**. The non-pawn correction values for both
key sides are then summed.

Also See:
https://github.com/zzzzz151/Starzix/commit/34911772f178c27b3a239dda0acb79c397c3a2f0
https://github.com/zzzzz151/Starzix/commit/33e0df8dd2db1d4775974ab12e3390154697f47a

The weights on the final correction value of the above correction
histories, as well as existing correction histories, are then tuned in
two separate SPSA sessions, totaling 75k games.

SPSA1:
https://tests.stockfishchess.org/tests/view/66e5243886d5ee47d953a86b
(Stopped early due to some weights reaching the maximum value)

SPSA2:
https://tests.stockfishchess.org/tests/view/66e6a26f86d5ee47d953a965

Also thanks to @martinnovaak, (Motor
https://github.com/martinnovaak/motor author) for insights and
suggestions.

Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 23328 W: 6197 L: 5901 D: 11230
Ptnml(0-2): 82, 2582, 6041, 2876, 83
https://tests.stockfishchess.org/tests/view/66e8787b86d5ee47d953ab6f

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 10626 W: 2826 L: 2560 D: 5240
Ptnml(0-2): 4, 1054, 2941, 1300, 14
https://tests.stockfishchess.org/tests/view/66e8ab2386d5ee47d953aba8

closes https://github.com/official-stockfish/Stockfish/pull/5598

Bench: 1011161
2024-09-17 21:01:43 +02:00
Michael ChalyandDisservin 240a5b1c72 Introduce separate butterfly history table for sorting root moves
Idea of this patch comes from the fact that current history heuristics
are mostly populated by low depth entries since our stat bonus reaches
maximum value at depth 5-6 and number of low depth nodes is much bigger
than number of high depth nodes. But it doesn't make a whole lost of
sense to use this low-depth centered histories to sort moves at root.
Current patch introduces special history table that is used exclusively
at root, it remembers which quiet moves were good and which quiet moves
were not good there and uses this information for move ordering.

Passed STC:
https://tests.stockfishchess.org/tests/view/66dda74adc53972b68218cc9
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 127680 W: 33579 L: 33126 D: 60975
Ptnml(0-2): 422, 15098, 32391, 15463, 466

Passed LTC:
https://tests.stockfishchess.org/tests/view/66dead2adc53972b68218d34
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 381978 W: 96958 L: 95923 D: 189097
Ptnml(0-2): 277, 42165, 105089, 43162, 296

closes https://github.com/official-stockfish/Stockfish/pull/5595

Bench: 1611283
2024-09-17 20:54:02 +02:00