09623abbe8
Simplify cutoffCnt further
...
Based off [Simplify cutoffCnt](https://github.com/official-stockfish/Stockfish/commit/69be04d38e10003853e78e4aa2b32aa252a82850 ) commit
Original
[commit](https://github.com/kennethlee33/Stockfish/commit/a77a895c3b7460f86b11a3ddfe3528f5be1276b9 )
adding extension condition seems to not be improving strength anymore
Passed STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 54176 W: 14331 L: 14125 D: 25720
Ptnml(0-2): 261, 6340, 13676, 6554, 257
https://tests.stockfishchess.org/tests/view/679edb7c0774dfd78deb0eed
Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 267198 W: 68148 L: 68179 D: 130871
Ptnml(0-2): 232, 30051, 73055, 30038, 223
https://tests.stockfishchess.org/tests/view/679ef2c70774dfd78deb0f43
closes https://github.com/official-stockfish/Stockfish/pull/5851
Bench: 3119355
2025-02-04 21:26:04 +01:00
9ed1725e78
Simplify bonusScale formula
...
Passed STC:
https://tests.stockfishchess.org/tests/view/679ea7bc0774dfd78deb0d68
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 47680 W: 12575 L: 12364 D: 22741
Ptnml(0-2): 179, 5589, 12139, 5708, 225
Passed LTC:
https://tests.stockfishchess.org/tests/view/679eb7760774dfd78deb0dbb
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 314220 W: 80110 L: 80189 D: 153921
Ptnml(0-2): 265, 35121, 86420, 35036, 268
closes https://github.com/official-stockfish/Stockfish/pull/5849
Bench: 3161782
2025-02-04 21:24:06 +01:00
fccc6f624e
Reduce full depth search twice
...
Passed STC:
https://tests.stockfishchess.org/tests/view/679f429e0774dfd78deb10a5
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 71584 W: 18905 L: 18529 D: 34150
Ptnml(0-2): 302, 8372, 18081, 8722, 315
Passed LTC:
https://tests.stockfishchess.org/tests/view/679f72a00774dfd78deb1102
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 353952 W: 91007 L: 90024 D: 172921
Ptnml(0-2): 375, 39163, 96921, 40138, 379
closes https://github.com/official-stockfish/Stockfish/pull/5848
Bench: 3642363
2025-02-04 21:22:08 +01:00
8c73472ac8
Simplify depth increase condition further
...
Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 51232 W: 13560 L: 13351 D: 24321
Ptnml(0-2): 183, 6075, 12920, 6226, 212
https://tests.stockfishchess.org/tests/view/679d7b2b0774dfd78deb043f
Passed Non-regression LTC (v. #5827 ):
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 172398 W: 44108 L: 44042 D: 84248
Ptnml(0-2): 122, 19207, 47489, 19245, 136
https://tests.stockfishchess.org/tests/view/679d7fb10774dfd78deb05d2
Passed Non-regression VLTC (v. #5827 ):
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 388540 W: 99314 L: 99464 D: 189762
Ptnml(0-2): 89, 40454, 113350, 40272, 105
https://tests.stockfishchess.org/tests/view/679da3be0774dfd78deb0ad4
closes https://github.com/official-stockfish/Stockfish/pull/5846
Bench: 2688175
2025-02-04 21:11:37 +01:00
9f0844c101
Simplify extensions depth increase condition
...
Passed STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 42784 W: 11198 L: 10979 D: 20607
Ptnml(0-2): 166, 5024, 10822, 5185, 195
https://tests.stockfishchess.org/tests/view/6795b6f8f6281b7d7b1869d6
Failed LTC:
LLR: -2.95 (-2.94,2.94) <-1.75,0.25>
Total: 283614 W: 72046 L: 72587 D: 138981
Ptnml(0-2): 241, 32097, 77647, 31606, 216
https://tests.stockfishchess.org/tests/view/6795cbb6f6281b7d7b186a07
Passed VLTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 59678 W: 15387 L: 15211 D: 29080
Ptnml(0-2): 23, 6169, 17273, 6357, 17
https://tests.stockfishchess.org/tests/view/6795c6dbf6281b7d7b1869f9
closes https://github.com/official-stockfish/Stockfish/pull/5827
Bench: 3088494
2025-02-02 13:52:16 +01:00
dabffbceff
Make pruning at ttpv nodes more aggressive
...
Continuation of work done by @FauziAkram and @Viren6 They had a series
of patches that decrease pruning for ttPv nodes - and it passed as a
gainer at lower time controls while revert passed as a gainer at higher
time controls.
So it's a logical continuation of this work that increases pruning for
ttPv nodes in hopes of scaling to longer TCs.
Fixed games STC:
https://tests.stockfishchess.org/tests/view/679ee3910774dfd78deb0efd
Elo: -4.98 ± 2.1 (95%) LOS: 0.0%
Total: 28584 W: 7229 L: 7639 D: 13716
Ptnml(0-2): 143, 3579, 7219, 3247, 104
nElo: -9.54 ± 4.0 (95%) PairsRatio: 0.90
Passed VVLTC with STC bounds:
https://tests.stockfishchess.org/tests/view/679d21f70774dfd78deaf553
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 323282 W: 83729 L: 83105 D: 156448
Ptnml(0-2): 37, 29842, 101269, 30446, 47
Passed VVLTC with LTC bounds:
https://tests.stockfishchess.org/tests/view/679e7a970774dfd78deb0cd3
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 113712 W: 29485 L: 29051 D: 55176
Ptnml(0-2): 13, 10376, 35640, 10818, 9
closes https://github.com/official-stockfish/Stockfish/pull/5844
Bench: 2964045
2025-02-02 13:47:52 +01:00
344e89275a
Simplify Away Quadruple Extensions
...
Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 95856 W: 24551 L: 24404 D: 46901
Ptnml(0-2): 85, 10621, 26364, 10778, 80
https://tests.stockfishchess.org/tests/view/679a9aedae346be6da0eebd6
Passed Non-regression VLTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 157536 W: 40000 L: 39921 D: 77615
Ptnml(0-2): 43, 16416, 45775, 16487, 47
https://tests.stockfishchess.org/tests/view/679aed8f51037ccaf3e30fbf
Passed Non-regression VVLTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 51598 W: 13345 L: 13172 D: 25081
Ptnml(0-2): 0, 4735, 16162, 4896, 6
https://tests.stockfishchess.org/tests/view/679d368b0774dfd78deb0163
closes https://github.com/official-stockfish/Stockfish/pull/5843
Bench: 2399312
2025-02-02 13:44:22 +01:00
c83ddd9e4b
Tweak correction history factors
...
The values are taken from this tuning
https://tests.stockfishchess.org/tests/view/679c4e150774dfd78deaf376
which added also a new material correction history. The full tune
doesn't work but ignoring the new history results in this changes.
Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 102368 W: 27057 L: 26638 D: 48673
Ptnml(0-2): 394, 12031, 25949, 12382, 428
https://tests.stockfishchess.org/tess/view/679d2ca70774dfd78deaf796
Passed LTC:
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 55044 W: 14215 L: 13855 D: 26974
Ptnml(0-2): 43, 5956, 15172, 6300, 51
https://tests.stockfishchess.org/tests/view/679d30be0774dfd78deafda2
closes https://github.com/official-stockfish/Stockfish/pull/5841
Bench: 3068583
2025-02-02 13:43:32 +01:00
7690fac5cf
Simp probcut disable condition
...
Disable probcut check when we the ttValue is not at least probCutBeta,
regardless of tt depth.
Passed simplification STC
LLR: 2.92 (-2.94,2.94) <-1.75,0.25>
Total: 60896 W: 16030 L: 15835 D: 29031
Ptnml(0-2): 220, 7164, 15507, 7315, 242
https://tests.stockfishchess.org/tests/view/679c0a3251037ccaf3e3141e
Passed simplification LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 76644 W: 19557 L: 19392 D: 37695
Ptnml(0-2): 50, 8486, 21104, 8613, 69
https://tests.stockfishchess.org/tests/view/679c380b0774dfd78deaf35c
closes https://github.com/official-stockfish/Stockfish/pull/5840
Bench: 3543770
2025-02-02 13:39:47 +01:00
40e0486d02
Make IIR for PvNodes less aggressive
...
In line with previous experiments on improving scaling of IIR.
Now it disables IIR for pv nodes with depth <= 2, so disallowing for it
to perform a qsearch dive.
Fixed games STC:
https://tests.stockfishchess.org/tests/view/679ae6a951037ccaf3e30fb3
Elo: -10.36 ± 2.5 (95%) LOS: 0.0%
Total: 20020 W: 4902 L: 5499 D: 9619
Ptnml(0-2): 128, 2653, 4976, 2194, 59
Passed VVLTC with STC bounds:
https://tests.stockfishchess.org/tests/view/67954f2e406a4efe9eb7d266
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 196758 W: 50725 L: 50258 D: 95775
Ptnml(0-2): 21, 18153, 61564, 18620, 21
Passed VVLTC with LTC bounds:
https://tests.stockfishchess.org/tests/view/6795a26bf6281b7d7b18698b
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 323092 W: 83679 L: 82857 D: 156556
Ptnml(0-2): 48, 29475, 101659, 30335, 29
closes https://github.com/official-stockfish/Stockfish/pull/5834
Bench: 3464332
2025-02-02 13:37:47 +01:00
5ef1f2b132
Refactor prior reduction
...
Make index of reduction consistent with rest of Stack
closes https://github.com/official-stockfish/Stockfish/pull/5832
No functional change
2025-02-02 13:36:58 +01:00
4a77fb213f
Clean up corrhist
...
Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 89056 W: 23225 L: 23067 D: 42764
Ptnml(0-2): 292, 9688, 24470, 9726, 352
https://tests.stockfishchess.org/tests/view/679816b2ae346be6da0ee8e7
closes https://github.com/official-stockfish/Stockfish/pull/5830
Bench: 1767398
2025-02-02 13:33:35 +01:00
f50d52aa7f
No Ply Restriction in the condition that limits the depth extension to a certain point
...
No Ply Restriction in the condition that limits the depth extension to a
certain point.
Passed again LTC rebased:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 195108 W: 49916 L: 49872 D: 95320
Ptnml(0-2): 170, 21846, 53464, 21918, 156
https://tests.stockfishchess.org/tests/view/6795542a406a4efe9eb7d361
closes https://github.com/official-stockfish/Stockfish/pull/5824
Bench: 1767398
2025-01-26 22:53:34 +01:00
ebdc7ba2da
Refactor prior countermove bonus
...
Passed simplification STC
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 155424 W: 40252 L: 40159 D: 75013
Ptnml(0-2): 511, 18655, 39328, 18666, 552
https://tests.stockfishchess.org/tests/view/6794084fe96bfb672ad18d90
Passed rebased simplification LTC
LLR: 2.97 (-2.94,2.94) <-1.75,0.25>
Total: 103944 W: 26567 L: 26427 D: 50950
Ptnml(0-2): 69, 11640, 28418, 11772, 73
https://tests.stockfishchess.org/tests/view/67955c9a406a4efe9eb7d7e4
closes https://github.com/official-stockfish/Stockfish/pull/5825
Bench: 1839554
2025-01-26 22:43:02 +01:00
a016abd698
Decrease all stats malus according to move count
...
Passed STC:
https://tests.stockfishchess.org/tests/view/6794c4634f7de645171fb341
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 28096 W: 7412 L: 7106 D: 13578
Ptnml(0-2): 97, 3194, 7148, 3524, 85
Passed LTC:
https://tests.stockfishchess.org/tests/view/6794ea13406a4efe9eb7d06b
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 58086 W: 15049 L: 14684 D: 28353
Ptnml(0-2): 27, 6344, 15957, 6667, 48
closes https://github.com/official-stockfish/Stockfish/pull/5823
Bench: 1711170
2025-01-26 22:42:41 +01:00
831cb01cea
Remove major corrhist
...
Remove major correction history and slightly increase all other
correction weights.
Passed STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 50080 W: 13171 L: 12959 D: 23950
Ptnml(0-2): 196, 5998, 12462, 6166, 218
https://tests.stockfishchess.org/tests/live_elo/67954526406a4efe9eb7d176
Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 51504 W: 13188 L: 12995 D: 25321
Ptnml(0-2): 54, 5658, 14128, 5865, 47
https://tests.stockfishchess.org/tests/live_elo/67954961406a4efe9eb7d251
closes https://github.com/official-stockfish/Stockfish/pull/5822
Bench: 2081366
2025-01-26 22:41:00 +01:00
69be04d38e
Simplify cutoffCnt
...
Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 235872 W: 61156 L: 61155 D: 113561
Ptnml(0-2): 843, 28269, 59658, 28376, 790
https://tests.stockfishchess.org/tests/view/6794dd3e4f7de645171fb380
Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 61494 W: 15644 L: 15462 D: 30388
Ptnml(0-2): 61, 6822, 16788, 7026, 50
https://tests.stockfishchess.org/tests/view/6794f86a406a4efe9eb7d093
closes https://github.com/official-stockfish/Stockfish/pull/5821
Bench: 2168937
2025-01-26 22:39:32 +01:00
27e747d1d7
Simplify futility margin in lmr for quiets.
...
Replace the "low bestValue condition" with whether there is a best move.
Passed Simplification STC
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 102560 W: 26517 L: 26367 D: 49676
Ptnml(0-2): 328, 12223, 26036, 12357, 336
https://tests.stockfishchess.org/tests/view/679310e4ca18a2c66da02af8
Passed Simplification LTC
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 66942 W: 17130 L: 16953 D: 32859
Ptnml(0-2): 52, 7459, 18290, 7600, 70
https://tests.stockfishchess.org/tests/view/679459a3e96bfb672ad18ddf
closes https://github.com/official-stockfish/Stockfish/pull/5820
Bench: 1438043
2025-01-25 20:59:33 +01:00
1b31e266b0
Consider more nodes as ttPv nodes.
...
Remove depth condition in propagation rule for ttPv state from a node to
it childs.
Because this change marks more nodes as ttPv, we have a time sensitive
ttPv reduction rule and the STC snd LTC seems to show bad scaling. So i
have also submitted a VLTC non-regression to check the scaling at higher
time control.
The results gives a little indication that we have perhaps good scaling
with more ttPv nodes so that could be further explored.
Passed non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 82528 W: 21627 L: 21453 D: 39448
Ptnml(0-2): 317, 9809, 20891, 9877, 370
https://tests.stockfishchess.org/tests/view/678e608cd63764e34db49ad7
Passed non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 310440 W: 78879 L: 78956 D: 152605
Ptnml(0-2): 255, 34915, 84938, 34876, 236
https://tests.stockfishchess.org/tests/view/678fab89ac8f8f5496155f3c
Passed non-regression VLTC for scaling verification:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 59496 W: 15158 L: 14983 D: 29355
Ptnml(0-2): 15, 6039, 17470, 6204, 20
https://tests.stockfishchess.org/tests/view/6794bd1f4f7de645171fb33b
closes https://github.com/official-stockfish/Stockfish/pull/5819
Bench: 1829507
2025-01-25 20:56:14 +01:00
889fed448c
Better nonpawn indexing
...
Improves indexing scheme, by noting that both sides are likely to access the same non_pawn_index nearby.
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 75936 W: 19905 L: 19554 D: 36477
Ptnml(0-2): 190, 7863, 21554, 8128, 233
https://tests.stockfishchess.org/tests/view/67904d0cfc8c306ba6cea332
closes https://github.com/official-stockfish/Stockfish/pull/5816
No functional change
Co-authored-by: Andrew Grant <andrew.github@grantnet.us >
2025-01-25 20:53:53 +01:00
435ba3dbb5
Revert "Moving up the if position is or has been on the PV reduction"
...
Passed VVLTC 1:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 68362 W: 17830 L: 17523 D: 33009
Ptnml(0-2): 9, 6253, 21347, 6566, 6
https://tests.stockfishchess.org/tests/view/6790271cfc8c306ba6cea2c1
Passed VVLTC 2:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 113256 W: 29158 L: 28721 D: 55377
Ptnml(0-2): 13, 10521, 35122, 10960, 12
https://tests.stockfishchess.org/tests/view/678d3e47d63764e34db491a3
closes https://github.com/official-stockfish/Stockfish/pull/5815
bench 1943998
2025-01-25 20:51:31 +01:00
6c7c5c7e47
Do not change TB cursed wins to draws if requested
...
If Syzygy50MoveRule is false, do not calls to is_draw() need to be guarded.
Also fixes a TB rootmove ranking issue in this case.
closes https://github.com/official-stockfish/Stockfish/pull/5814
No functional change
2025-01-25 20:42:50 +01:00
75b75bc16a
Add improving to a condition of NMP
...
This patch makes one of the conditions for null-move pruning depend on whether we're improving. Keep in mind that it relies on the "classical" definiton, rather than the refined one.
Passed STC: https://tests.stockfishchess.org/tests/view/678d5267d63764e34db49720
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 38976 W: 10296 L: 9974 D: 18706
Ptnml(0-2): 135, 4504, 9902, 4798, 149
Passed LTC: https://tests.stockfishchess.org/tests/view/678d5891d63764e34db49731
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 275772 W: 70655 L: 69836 D: 135281
Ptnml(0-2): 217, 30615, 75394, 31452, 208
closes https://github.com/official-stockfish/Stockfish/pull/5813
Bench: 2475787
2025-01-25 20:41:37 +01:00
aa894c0f93
Comments Tweak
...
* Remove from comments, hardcoded exact values for parameters that are subject to tuning.
* Remove the Elo worth, as they are now completely outdated, making them irrelevant and potentially misleading.
* Consolidated scaling-related comments into a single section for clarity. Used asterisks (*) to highlight parameters significantly affected by scaling, given their separation in the code.
closes https://github.com/official-stockfish/Stockfish/pull/5810
No functional change
2025-01-25 20:29:40 +01:00
4975b2bc6f
Increase prior countermove bonus if TT move
...
Passed STC:
https://tests.stockfishchess.org/tests/view/678c4c8bf4dc0a8b4ae8db5c
LLR: 2.97 (-2.94,2.94) <0.00,2.00>
Total: 273408 W: 71089 L: 70415 D: 131904
Ptnml(0-2): 937, 32466, 69229, 33130, 942
Passed LTC:
https://tests.stockfishchess.org/tests/view/678ccabdf4dc0a8b4ae8dd7a
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 148614 W: 38138 L: 37584 D: 72892
Ptnml(0-2): 97, 16450, 40689, 16944, 127
closes https://github.com/official-stockfish/Stockfish/pull/5809
Bench: 1582867
2025-01-25 20:27:11 +01:00
59c578ad28
Add move count based reduction.
...
Do less reduction which is linear increasing with move count (factor = 64).
Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 191488 W: 49982 L: 49432 D: 92074
Ptnml(0-2): 731, 22523, 48614, 23217, 659
https://tests.stockfishchess.org/tests/view/678d0b29d63764e34db4904b
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 90582 W: 23150 L: 22717 D: 44715
Ptnml(0-2): 73, 9936, 24822, 10405, 55
https://tests.stockfishchess.org/tests/view/678d347cd63764e34db4916f
closes https://github.com/official-stockfish/Stockfish/pull/5807
Bench: 1803474
2025-01-25 20:23:33 +01:00
8e3e22b3d4
Replace depth increase condition with !opponentWorsening
...
Passed simplification STC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 220544 W: 57417 L: 57399 D: 105728
Ptnml(0-2): 816, 26554, 55540, 26520, 842
https://tests.stockfishchess.org/tests/view/678970e38082388fa0cbfe02
Passed simplification LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 132600 W: 33868 L: 33760 D: 64972
Ptnml(0-2): 126, 14770, 36390, 14898, 116
https://tests.stockfishchess.org/tests/view/678accabc00c743bc9e9fc7f
closes https://github.com/official-stockfish/Stockfish/pull/5798
bench 1632964
2025-01-18 21:33:17 +01:00
f00d91f8ac
Refine probcut
...
Allow probcut for depth 3 and disable deeper verification search when it would simply repeat the qsearch.
Passed STC
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 283232 W: 74450 L: 73760 D: 135022
Ptnml(0-2): 1052, 33780, 71349, 34296, 1139
https://tests.stockfishchess.org/tests/view/67843b58460e2910c51ddcc6
Passed LTC
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 339654 W: 86845 L: 85893 D: 166916
Ptnml(0-2): 298, 37734, 92802, 38704, 289
https://tests.stockfishchess.org/tests/view/678aa722c00c743bc9e9face
closes https://github.com/official-stockfish/Stockfish/pull/5797
bench 1288648
2025-01-18 21:27:42 +01:00
738ac2a100
tuned TM values
...
Tuned 70k games at 240+2.4 th 2: https://tests.stockfishchess.org/tests/view/6783b1b16ddf09c0b4b703f5
Failed STC:
LLR: -2.93 (-2.94,2.94) <0.00,2.00>
Total: 491872 W: 128260 L: 127804 D: 235808
Ptnml(0-2): 1579, 55449, 131572, 55609, 1727
https://tests.stockfishchess.org/tests/view/6785a045460e2910c51de4b8
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 154824 W: 39315 L: 38874 D: 76635
Ptnml(0-2): 110, 15809, 45147, 16222, 124
https://tests.stockfishchess.org/tests/view/678ac722c00c743bc9e9fc35
Passed VLTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 77404 W: 19825 L: 19452 D: 38127
Ptnml(0-2): 18, 7262, 23765, 7643, 14
https://tests.stockfishchess.org/tests/view/678b2a98c00c743bc9ea048c
closes https://github.com/official-stockfish/Stockfish/pull/5796
No functional change
2025-01-18 21:24:01 +01:00
c94bcf62e4
Moving up the if position is or has been on the PV reduction
...
Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 29664 W: 7880 L: 7570 D: 14214
Ptnml(0-2): 93, 3487, 7390, 3741, 121
https://tests.stockfishchess.org/tests/view/678ac957c00c743bc9e9fc3f
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 81354 W: 20903 L: 20487 D: 39964
Ptnml(0-2): 66, 9003, 22123, 9419, 66
https://tests.stockfishchess.org/tests/view/678ad359c00c743bc9e9fcfa
closes https://github.com/official-stockfish/Stockfish/pull/5794
Bench: 1414638
2025-01-18 21:18:48 +01:00
7701d0b3c4
Introduce one more continuation history
...
This one is counter counter counter history - with really low update value and divided by 3 in movepicker unlike the other ones.
Passed STC:
https://tests.stockfishchess.org/tests/view/67861495460e2910c51de720
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 44352 W: 11699 L: 11370 D: 21283
Ptnml(0-2): 156, 5098, 11361, 5383, 178
Passed LTC:
https://tests.stockfishchess.org/tests/view/6786e89e3b8f206a2696b646
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 432660 W: 110355 L: 109207 D: 213098
Ptnml(0-2): 381, 48214, 118039, 49268, 428
closes https://github.com/official-stockfish/Stockfish/pull/5792
Bench: 1491837
2025-01-18 21:04:55 +01:00
b392ac76db
Increase history bonus of TT moves
...
Passed STC:
https://tests.stockfishchess.org/tests/view/678807653b8f206a2696b78b
LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 42208 W: 11113 L: 10783 D: 20312
Ptnml(0-2): 148, 4919, 10651, 5227, 159
Passed LTC:
https://tests.stockfishchess.org/tests/view/6788a8463b8f206a2696b956
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 122886 W: 31454 L: 30952 D: 60480
Ptnml(0-2): 105, 13567, 33619, 14025, 127
closes https://github.com/official-stockfish/Stockfish/pull/5791
Bench: 1760081
2025-01-18 21:02:04 +01:00
ccbd060b01
simplify razoring
...
Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 93056 W: 24215 L: 24054 D: 44787
Ptnml(0-2): 364, 11085, 23470, 11244, 365
https://tests.stockfishchess.org/tests/view/67883a5d3b8f206a2696b804
Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 66564 W: 16971 L: 16794 D: 32799
Ptnml(0-2): 56, 7403, 18192, 7570, 61
https://tests.stockfishchess.org/tests/view/6789ffa78082388fa0cbfe95
closes https://github.com/official-stockfish/Stockfish/pull/5788
bench 1500649
2025-01-18 20:54:55 +01:00
a944f08225
retroactive reduction decrease if eval improves
...
If the previous reduction was large but the static eval improves then increase the search depth. This patch looks at the next node when calculating the reduction, something I don't think has been done before and which can probably used for further elo gaining patches.
Passed STC
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 55936 W: 14813 L: 14462 D: 26661
Ptnml(0-2): 220, 6565, 14094, 6822, 267
https://tests.stockfishchess.org/tests/view/67845b70460e2910c51ddcff
Passed LTC
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 189468 W: 48411 L: 47773 D: 93284
Ptnml(0-2): 180, 20801, 52131, 21445, 177
https://tests.stockfishchess.org/tests/view/6784e2cb460e2910c51ddf86
closes https://github.com/official-stockfish/Stockfish/pull/5785
bench: 1512884
2025-01-18 20:50:04 +01:00
4c2241089d
Remove addition of 1ms to all timestamps
...
The +1 was a quick fix to avoid the division by zero, a more correct approach is to use 1ms as the minimum reported timestamp to avoid a division by zero.
Later timestamps no longer include an additional 1ms.
closes https://github.com/official-stockfish/Stockfish/pull/5778
No functional change
2025-01-18 20:32:00 +01:00
5868b4cb58
remove eval== staticeval check in fut pruning
...
Simplify corrplexity in futility margin
Don't check that staticEval == eval when applying the corrplexity-based adjustment in futility pruning.
Passed Simplification STC
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 121760 W: 31640 L: 31512 D: 58608
Ptnml(0-2): 349, 14400, 31289, 14458, 384
https://tests.stockfishchess.org/tests/view/6780c4109168c8bf30927777
Passed Simplification LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 134772 W: 34245 L: 34140 D: 66387
Ptnml(0-2): 94, 14869, 37350, 14984, 89
https://tests.stockfishchess.org/tests/view/6782d6ea6ddf09c0b4b6dd36
closes https://github.com/official-stockfish/Stockfish/pull/5776
Bench: 1487627
2025-01-18 20:25:59 +01:00
aaafaaecf2
prefetch in do_move()
...
this allows removing Position::key_after()
STC
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 24960 W: 6556 L: 6336 D: 12068
Ptnml(0-2): 59, 2554, 7056, 2730, 81
LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 115080 W: 29319 L: 29204 D: 56557
Ptnml(0-2): 51, 10736, 35864, 10825, 64
STC with 2MB hash
LLR: 3.04 (-2.94,2.94) <-1.75,0.25>
Total: 182176 W: 46998 L: 46932 D: 88246
Ptnml(0-2): 526, 19711, 50544, 19785, 522
LTC with 8MB hash
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 441180 W: 111557 L: 111746 D: 217877
Ptnml(0-2): 229, 39698, 140929, 39501, 233
closes https://github.com/official-stockfish/Stockfish/pull/5770
bench: 1379150
2025-01-18 20:19:53 +01:00
c085670b84
Increase the depth margin
...
Tested at VVLTC against the passed patches.
Test 1 against PR5764
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 167260 W: 43053 L: 42521 D: 81686
Ptnml(0-2): 7, 15272, 52542, 15800, 9
https://tests.stockfishchess.org/tests/view/6782ef196ddf09c0b4b6e780
Test 2 against PR5765
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 300012 W: 77364 L: 76771 D: 145877
Ptnml(0-2): 22, 27555, 94256, 28154, 19
https://tests.stockfishchess.org/tests/view/678366446ddf09c0b4b7028c
closes https://github.com/official-stockfish/Stockfish/pull/5768
Bench: 1379150
2025-01-12 21:36:39 +01:00
e2612f9a29
Introduce Correction History Quad Extensions
...
Also modifies the double and triple extension margins with the correction history adjustment.
STC Elo Estimate:
Elo: -4.40 ± 1.4 (95%) LOS: 0.0%
Total: 60000 W: 15230 L: 15990 D: 28780
Ptnml(0-2): 264, 7495, 15168, 6883, 190
nElo: -8.48 ± 2.8 (95%) PairsRatio: 0.91
https://tests.stockfishchess.org/tests/view/6783a3786ddf09c0b4b703a1
Passed 1st VVLTC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 35736 W: 9354 L: 9088 D: 17294
Ptnml(0-2): 4, 3191, 11212, 3457, 4
https://tests.stockfishchess.org/tests/view/6783a3336ddf09c0b4b7039b
Passed 2nd VVLTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 36394 W: 9515 L: 9225 D: 17654
Ptnml(0-2): 1, 3271, 11364, 3559, 2
https://tests.stockfishchess.org/tests/view/678395e26ddf09c0b4b70345
closes https://github.com/official-stockfish/Stockfish/pull/5767
Bench: 1567166
2025-01-12 21:36:39 +01:00
93edf7a74c
VVLTC Search Tune
...
Values were tuned with 118k VVLTC games.
Tested against #5764 .
Passed VVLTC 1st sprt:
https://tests.stockfishchess.org/tests/view/678331226ddf09c0b4b6fd78
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 43556 W: 11219 L: 10942 D: 21395
Ptnml(0-2): 2, 3975, 13549, 4248, 4
Passed VVLTC 2nd sprt:
https://tests.stockfishchess.org/tests/view/67834aa06ddf09c0b4b6fe34
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 37150 W: 9577 L: 9285 D: 18288
Ptnml(0-2): 2, 3344, 11593, 3632, 4
closes https://github.com/official-stockfish/Stockfish/pull/5765
Bench: 1258128
2025-01-12 21:36:31 +01:00
8b32e4825f
Make IIR less aggressive
...
This patch is an elo gaining simplification which gains elo at longer time controls.
Patch disallows IIR for cutNodes with existing tt moves as well as makes
IIR for pv nodes less aggressive, basiclally confirming suspected
scaling patterns for this heuristic.
Result of 50k games STC run:
https://tests.stockfishchess.org/tests/view/678304676ddf09c0b4b6f9f9
Elo: -2.93 ± 1.6 (95%) LOS: 0.0%
Total: 50000 W: 12718 L: 13140 D: 24142
Ptnml(0-2): 189, 6087, 12835, 5735, 154
nElo: -5.71 ± 3.0 (95%) PairsRatio: 0.94
Passed VVLTC SPRT with STC bounds:
https://tests.stockfishchess.org/tests/view/6782eb1a6ddf09c0b4b6e6b0
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 150292 W: 38868 L: 38458 D: 72966
Ptnml(0-2): 19, 13890, 46907, 14322, 8
Passed VVLTC SPRT with LTC bounds:
https://tests.stockfishchess.org/tests/view/6782d8d96ddf09c0b4b6df18
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 153388 W: 39791 L: 39285 D: 74312
Ptnml(0-2): 13, 13924, 48311, 14436, 10
closes https://github.com/official-stockfish/Stockfish/pull/5763
Bench: 1507606
2025-01-12 21:25:36 +01:00
b84c8807a3
Optimize attackers_to()
...
https://tests.stockfishchess.org/tests/view/6782decb6ddf09c0b4b6e1b0
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 105920 W: 27571 L: 27181 D: 51168
Ptnml(0-2): 284, 10808, 30403, 11164, 301
- If we only need to know if attackers exist we can skip some
calculations.
- Also calculating slider/magic attackers first is better because the
double lookup is slow due to memory latency.
- I also included a couple of very minor cleanups in search that
probably don't warrant their own PR but I can open separately if
that's better.
closes https://github.com/official-stockfish/Stockfish/pull/5762
No functional change
2025-01-12 21:24:44 +01:00
921361829a
Simplify away capthist bonus in Probcut
...
The explicit bonus has been obsoleted with the introduction of #5695
Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 132832 W: 34519 L: 34403 D: 63910
Ptnml(0-2): 430, 15754, 33931, 15872, 429
https://tests.stockfishchess.org/tests/view/678158c49168c8bf30927834
Passed Non-regression LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 123492 W: 31426 L: 31309 D: 60757
Ptnml(0-2): 79, 13705, 34051, 13842, 69
https://tests.stockfishchess.org/tests/view/6782b07e6ddf09c0b4b6dbb7
closes https://github.com/official-stockfish/Stockfish/pull/5761
Bench: 1180439
2025-01-12 21:23:29 +01:00
28c07fb456
Simplify Probcut Condition
...
Rebased and properly guarded #5720
Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 179616 W: 45764 L: 45706 D: 88146
Ptnml(0-2): 125, 19665, 50162, 19739, 117
https://tests.stockfishchess.org/tests/view/677590531a2f267f20548b82
Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 445728 W: 113467 L: 113682 D: 218579
Ptnml(0-2): 331, 49226, 123900, 49141, 266
https://tests.stockfishchess.org/tests/view/67734f351a2f267f205489d9
closes https://github.com/official-stockfish/Stockfish/pull/5758
Bench: 1180421
2025-01-12 21:18:39 +01:00
c88a5b3950
Simplify away hint for common parent position at probcut
...
Since it's introduction at probcut step the nnue network has changed
substantially and now it no longer seems useful.
Passed non-regression test at STC
https://tests.stockfishchess.org/tests/view/675fe27986d5ee47d9542d86
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 118656 W: 30732 L: 30609 D: 57315
Ptnml(0-2): 319, 12767, 33049, 12858, 335
N.B.: It may be useful to reintroduce it here at probcut if we know that
a node that was cut away previously now has to be explored. Exploring
new ground will deliver no tt-hits so in this case the hint for common
parent position might be useful.
No functional change
2025-01-12 21:15:35 +01:00
403a5e100b
Simplify Fail-Low Bonus
...
Passed Non-regression STC:
LLR: 2.92 (-2.94,2.94) <-1.75,0.25>
Total: 66592 W: 17426 L: 17239 D: 31927
Ptnml(0-2): 208, 7812, 17109, 7919, 248
https://tests.stockfishchess.org/tests/view/6774e1711a2f267f20548b22
Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 179616 W: 45764 L: 45706 D: 88146
Ptnml(0-2): 125, 19665, 50162, 19739, 117
https://tests.stockfishchess.org/tests/view/677590531a2f267f20548b82
closes https://github.com/official-stockfish/Stockfish/pull/5751
Bench: 1310158
2025-01-12 21:14:11 +01:00
5370c3035e
Refactor Stats Array
...
* Limit use of `StatsEntry` wrapper to arithmetic types
* Generalize `Stats` to `MultiArray` by discarding the template parameter `D`
* Allow `MultiArray::fill` to take any type assignable to element type
* Remove now-unused operator overloads on `StatsEntry`
closes https://github.com/official-stockfish/Stockfish/pull/5750
No functional change
2025-01-12 21:13:14 +01:00
d1a1ff4f17
Simplify Razoring
...
Passed Non-regression STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 95584 W: 24906 L: 24750 D: 45928
Ptnml(0-2): 285, 11227, 24632, 11343, 305
https://tests.stockfishchess.org/tests/view/675e0ed286d5ee47d95429ee
Passed Non-regression LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 191292 W: 48637 L: 48589 D: 94066
Ptnml(0-2): 97, 21061, 53276, 21121, 91
https://tests.stockfishchess.org/tests/view/675f08c686d5ee47d9542be3
closes https://github.com/official-stockfish/Stockfish/pull/5724
Bench: 1286274
2025-01-12 21:11:27 +01:00
c76c179361
Remove non-functional std::min()
...
closes https://github.com/official-stockfish/Stockfish/pull/5749
No functional change
2025-01-06 00:48:05 +01:00
1611b9c940
Corrplexity for futility pruning
...
Add corrhist-based term to futility margin
Inspired by a recent patch of Shawn Xu, this tweak increases the margin
over beta needed to futility prune based on the correction history, with
an offset.
Passed STC
LLR: 2.97 (-2.94,2.94) <0.00,2.00>
Total: 545504 W: 141957 L: 140885 D: 262662
Ptnml(0-2): 1829, 64226, 139551, 65336, 1810
https://tests.stockfishchess.org/tests/view/67634a8386d5ee47d95439db
Passed LTC
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 125994 W: 32199 L: 31695 D: 62100
Ptnml(0-2): 97, 13742, 34798, 14280, 80
https://tests.stockfishchess.org/tests/view/6765cf9986d5ee47d9544217
closes https://github.com/official-stockfish/Stockfish/pull/5748
Bench: 999324
2025-01-06 00:46:30 +01:00
Kenneth Lee