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Author SHA1 Message Date
DubslowandJoost VandeVondele 442c40b43d Use NNUE complexity in search, retune related parameters 
This builds on ideas of xoto10 and mstembera to use more output from NNUE in the search algorithm.

passed STC:
https://tests.stockfishchess.org/tests/view/62ae454fe7ee5525ef88a957
LLR: 2.95 (-2.94,2.94) <0.00,2.50>
Total: 89208 W: 24127 L: 23753 D: 41328
Ptnml(0-2): 400, 9886, 23642, 10292, 384

passed LTC:
https://tests.stockfishchess.org/tests/view/62acc6ddd89eb6cf1e0750a1
LLR: 2.93 (-2.94,2.94) <0.50,3.00>
Total: 56352 W: 15430 L: 15115 D: 25807
Ptnml(0-2): 44, 5501, 16782, 5794, 55

closes https://github.com/official-stockfish/Stockfish/pull/4088

bench 5332964
 2022-06-20 08:30:57 +02:00
DubslowandJoost VandeVondele 5304b561ab LMR: remove deeper 
...apparently it wasn't doing much anymore. inspired by rufish's recent attempts to improve this.

passed STC:
https://tests.stockfishchess.org/tests/view/62abca2cd89eb6cf1e072c04
LLR: 2.95 (-2.94,2.94) <-2.25,0.25>
Total: 85576 W: 22766 L: 22683 D: 40127
Ptnml(0-2): 362, 9607, 22741, 9742, 336

passed LTC:
https://tests.stockfishchess.org/tests/view/62ac90ffd89eb6cf1e07488f
LLR: 2.93 (-2.94,2.94) <-2.25,0.25>
Total: 48248 W: 13018 L: 12896 D: 22334
Ptnml(0-2): 32, 4773, 14400, 4879, 40

closes https://github.com/official-stockfish/Stockfish/pull/4088

bench 5578988
 2022-06-20 08:25:50 +02:00
bmc4andJoost VandeVondele 4d6a11a04c Don't change ttPv at probCut 
STC:
LLR: 2.96 (-2.94,2.94) <-2.25,0.25>
Total: 35672 W: 9618 L: 9462 D: 16592
Ptnml(0-2): 151, 3890, 9601, 4040, 154
https://tests.stockfishchess.org/tests/view/62ab03f750949cfc241b1965

LTC:
LLR: 2.93 (-2.94,2.94) <-2.25,0.25>
Total: 54160 W: 14626 L: 14511 D: 25023
Ptnml(0-2): 42, 5414, 16056, 5523, 45
https://tests.stockfishchess.org/tests/view/62ab5e6fd89eb6cf1e071b87

closes https://github.com/official-stockfish/Stockfish/pull/4088

bench: 5798229
 2022-06-20 08:24:07 +02:00
bmc4andJoost VandeVondele 6edc29d720 Simplify away condition in ttSave in probCut 
Remove condition for tte->save in probCut so it always saves on probCut cutoff.

STC:
LLR: 2.95 (-2.94,2.94) <-2.25,0.25>
Total: 47848 W: 12921 L: 12782 D: 22145
Ptnml(0-2): 207, 5340, 12715, 5431, 231
https://tests.stockfishchess.org/tests/view/62a1f7c87bd8e641e44436f7

LTC:
LLR: 2.97 (-2.94,2.94) <-2.25,0.25>
Total: 132736 W: 35895 L: 35881 D: 60960
Ptnml(0-2): 109, 13384, 39360, 13414, 101
https://tests.stockfishchess.org/tests/view/62a2421a7bd8e641e444434f

closes https://github.com/official-stockfish/Stockfish/pull/4069

bench: 5845802
 2022-06-16 07:12:01 +02:00
mstemberaandJoost VandeVondele 2d5dcf3d18 Minor simplifications and cleanup in search 
STC: https://tests.stockfishchess.org/tests/view/629d6775593a4a9b6482c1ec
LLR: 2.93 (-2.94,2.94) <-2.25,0.25>
Total: 77416 W: 20683 L: 20589 D: 36144
Ptnml(0-2): 317, 8690, 20620, 8744, 337

LTC: https://tests.stockfishchess.org/tests/view/629db4be593a4a9b6482ceef
LLR: 2.95 (-2.94,2.94) <-2.25,0.25>
Total: 106544 W: 28752 L: 28705 D: 49087
Ptnml(0-2): 97, 10692, 31641, 10751, 91

closes https://github.com/official-stockfish/Stockfish/pull/4059

Bench: 5913510
 2022-06-16 07:06:43 +02:00
ppigazziniandJoost VandeVondele d54b85b4bd Restore NDKv21 for GitHub Actions 
GitHub updated the versions of NDK installed on the Actions runners
breaking the ARM tests.
Restore the NDKv21 using the GitHub suggested mitigation, see:
https://github.com/actions/virtual-environments/issues/5595

closes https://github.com/official-stockfish/Stockfish/pull/4077

No functional change
 2022-06-16 07:03:52 +02:00
candirufishandJoost VandeVondele 00297cfef0 Use qsearch on step 11 if depth is equal to or below 0 
larger reduction of depth if no TT entry is found, and go in qsearch as needed.

stc:
https://tests.stockfishchess.org/tests/view/629dfacd593a4a9b6482db72
LLR: 2.93 (-2.94,2.94) <0.00,2.50>
Total: 31920 W: 8591 L: 8322 D: 15007
Ptnml(0-2): 127, 3551, 8376, 3738, 168

ltc:
https://tests.stockfishchess.org/tests/view/629e304e593a4a9b6482e451
LLR: 2.95 (-2.94,2.94) <0.50,3.00>
Total: 17488 W: 4842 L: 4614 D: 8032
Ptnml(0-2): 13, 1670, 5151, 1896, 14

closes https://github.com/official-stockfish/Stockfish/pull/4056

Bench: 5870283
 2022-06-07 08:34:14 +02:00
Boštjan MejakandJoost VandeVondele 809849fa27 Wording of help output and comments. 
Improved the output text that is diplayed when executing the 'help' command.
Also, some comments were fixed along the way.

closes https://github.com/official-stockfish/Stockfish/pull/4048
closes https://github.com/official-stockfish/Stockfish/pull/4044

No functional change
 2022-06-07 08:30:07 +02:00
DubslowandJoost VandeVondele 90cf8e7d2b Remove LMR condition for complex pos 
Inspired by Kia's similar test: https://tests.stockfishchess.org/tests/view/6292898c1e7cd5f29966fbe0

Passed STC:
https://tests.stockfishchess.org/tests/view/62941588b0d5a7d1b780ed4b
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 266872 W: 70850 L: 71033 D: 124989
Ptnml(0-2): 1180, 30114, 70941, 30111, 1090

Passed LTC:
https://tests.stockfishchess.org/tests/view/62964a754628d33daa24f062
LLR: 2.95 (-2.94,2.94) <-2.25,0.25>
Total: 70160 W: 18756 L: 18662 D: 32742
Ptnml(0-2): 42, 6976, 20950, 7070, 42

closes https://github.com/official-stockfish/Stockfish/pull/4047

Bench 6237567
 2022-06-02 07:49:31 +02:00
xoto10andJoost VandeVondele 7f1333ccf8 Blend nnue complexity with classical. 
Following mstembera's test of the complexity value derived from nnue values,
this change blends that idea with the old complexity calculation.

STC 10+0.1:
LLR: 2.95 (-2.94,2.94) <0.00,2.50>
Total: 42320 W: 11436 L: 11148 D: 19736
Ptnml(0-2): 209, 4585, 11263, 4915, 188
https://tests.stockfishchess.org/tests/live_elo/6295c9239c8c2fcb2bad7fd9

LTC 60+0.6:
LLR: 2.98 (-2.94,2.94) <0.50,3.00>
Total: 34600 W: 9393 L: 9125 D: 16082
Ptnml(0-2): 32, 3323, 10319, 3597, 29
https://tests.stockfishchess.org/tests/view/6295fd5d9c8c2fcb2bad88cf

closes https://github.com/official-stockfish/Stockfish/pull/4046

Bench 6078140
 2022-06-02 07:47:23 +02:00
candirufishandJoost VandeVondele 653bd0817c cutnode and movecount lmr extension simplification 
Passed STC
https://tests.stockfishchess.org/tests/view/6294133cb0d5a7d1b780ece3
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 41072 W: 11052 L: 10908 D: 19112
Ptnml(0-2): 153, 4324, 11461, 4422, 176

Passed LTC
ltc: https://tests.stockfishchess.org/tests/view/62947ae6b0d5a7d1b780fe86
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 102736 W: 27509 L: 27459 D: 47768
Ptnml(0-2): 98, 9734, 31669, 9754, 113

closes https://github.com/official-stockfish/Stockfish/pull/4045

Bench: 6410652
 2022-06-02 07:44:22 +02:00
Michael ChalyandJoost VandeVondele 8fadbcf1b2 Add info about elo gained from some heuristics 
Add info about qsearch and impact of main and continuation histories.

Based on these tests:
https://tests.stockfishchess.org/tests/view/62946ffcb0d5a7d1b780fc7e
https://tests.stockfishchess.org/tests/view/628facb71e7cd5f299669534
https://tests.stockfishchess.org/tests/view/628eade11e7cd5f299666f2e

closes https://github.com/official-stockfish/Stockfish/pull/4041

No functional change.
 2022-06-02 07:43:14 +02:00
xoto10andJoost VandeVondele 4c7de9e8ab Adjust scale param higher 
xoto10's scaleopt tune resulted in a yellow LTC, but the main parameter shift looked almost exactly like the tune rate reduction schedule,
so further increases of that param were tried. Joint work xoto10 and dubslow.

passed LTC:
https://tests.stockfishchess.org/tests/view/628c709372775f382300f03e
LLR: 2.93 (-2.94,2.94) <0.50,3.00>
Total: 70112 W: 18932 L: 18584 D: 32596
Ptnml(0-2): 66, 6904, 20757, 7274, 55

failed STC:
https://tests.stockfishchess.org/tests/view/6290e4441e7cd5f29966bdc8
LLR: -2.96 (-2.94,2.94) <0.00,2.50>
Total: 59976 W: 15919 L: 16018 D: 28039
Ptnml(0-2): 250, 6791, 15974, 6754, 219

similar LTC's were yellow
first yellow LTC: https://tests.stockfishchess.org/tests/view/6288a33f817227d3e5c5b05d
double exaggerate yellow: https://tests.stockfishchess.org/tests/live_elo/628e140372775f38230129a6
triple exaggerate yellow: https://tests.stockfishchess.org/tests/live_elo/628e2caf72775f3823012d45

closes https://github.com/official-stockfish/Stockfish/pull/4036

bench 6410652
 2022-05-29 19:14:20 +02:00
proukornewandJoost VandeVondele 6ede1bed89 Improve handling of variables set in the make environment 
removes duplication on the commandline for example in a profile-build

closes https://github.com/official-stockfish/Stockfish/pull/3859

No functional change
 2022-05-29 19:04:25 +02:00
Giacomo LorenzettiandJoost VandeVondele 1a168201bd Small speedup in futility_move_count 
The speedup is around 0.25% using gcc 11.3.1 (bmi2, nnue bench, depth 16
and 23) while it is neutral using clang (same conditions).

According to `perf` that integer division was one of the most time-consuming
instructions in search (gcc disassembly).

Passed STC:
https://tests.stockfishchess.org/tests/view/628a17fe24a074e5cd59b3aa
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 22232 W: 5992 L: 5751 D: 10489
Ptnml(0-2): 88, 2235, 6218, 2498, 77

yellow LTC:
https://tests.stockfishchess.org/tests/view/628a35d7ccae0450e35106f7
LLR: -2.95 (-2.94,2.94) <0.50,3.00>
Total: 320168 W: 85853 L: 85326 D: 148989
Ptnml(0-2): 185, 29698, 99821, 30165, 215

This patch also suggests that UHO STC is sensible to small speedups (< 0.50%).

closes https://github.com/official-stockfish/Stockfish/pull/4032

No functional change
 2022-05-29 18:54:19 +02:00
Joost VandeVondele 48df0754bc Add command line flags to link to information 
This patch provides command line flags `--help` and `--license` as well as the corresponding `help` and `license` commands.

```
$ ./stockfish --help
Stockfish 200522 by the Stockfish developers (see AUTHORS file)

Stockfish is a powerful chess engine and free software licensed under the GNU GPLv3.
Stockfish is normally used with a separate graphical user interface (GUI).
Stockfish implements the universal chess interface (UCI) to exchange information.
For further information see https://github.com/official-stockfish/Stockfish#readme
or the corresponding README.md and Copying.txt files distributed with this program.

```

The idea is to provide a minimal help that links to the README.md file,
not replicating information that is already available elsewhere.

We use this opportunity to explicitly report the license as well.

closes https://github.com/official-stockfish/Stockfish/pull/4027

No functional change.
 2022-05-29 18:46:35 +02:00
Giacomo LorenzettiandJoost VandeVondele f7d1491b3d Assorted small cleanups 
closes https://github.com/official-stockfish/Stockfish/pull/3973

No functional change
 2022-05-29 18:42:48 +02:00
candirufishandStéphane Nicolet cc7bcd5303 Simplify a condition 
Principal variation depth late move reduction extension simplification.

stc:
https://tests.stockfishchess.org/tests/view/6285a1d19d18a78568e7fa24
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 428536 W: 113433 L: 113851 D: 201252
Ptnml(0-2): 1671, 48606, 114090, 48272, 1629

ltc:
https://tests.stockfishchess.org/tests/view/62871d20375cdc5de8cf5db3
LLR: 2.95 (-2.94,2.94) <-2.25,0.25>
Total: 56792 W: 15123 L: 15011 D: 26658
Ptnml(0-2): 42, 5681, 16825, 5819, 29

closes https://github.com/official-stockfish/Stockfish/pull/4028

bench: 6501437
 2022-05-21 12:42:33 +02:00
xoto10andJoost VandeVondele 22b7909809 Tune scale and optimism. 
Tune scale and optimism in effort to make stockfish play more aggressively.

STC @ 10+0.1 th 1:
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 27896 W: 7506 L: 7248 D: 13142
Ptnml(0-2): 103, 3047, 7388, 3309, 101
https://tests.stockfishchess.org/tests/live_elo/627fd0cfab44257388ab1f13

LTC @ 60+0.6 th 1:
LLR: 2.93 (-2.94,2.94) <0.50,3.00>
Total: 65576 W: 17512 L: 17178 D: 30886
Ptnml(0-2): 37, 6397, 19587, 6729, 38
https://tests.stockfishchess.org/tests/live_elo/627ff666ab44257388ab256d

closes https://github.com/official-stockfish/Stockfish/pull/4025

Bench 6407734
 2022-05-15 20:20:37 +02:00
disservinandJoost VandeVondele 5372f81cc8 SE depth scaling using the previous depth 
This patch makes the SE depth condition more robust and allows it to scale with completed depth
from a previous search.

At long TC this patch is almost equivalent to https://github.com/official-stockfish/Stockfish/pull/4016 which had

VLTC:
https://tests.stockfishchess.org/tests/view/626abd7e8707aa698c0093a8
Elo: 2.35 +-1.5 (95%) LOS: 99.9%
Total: 40000 W: 10991 L: 10720 D: 18289
Ptnml(0-2): 8, 3534, 12648, 3799, 11
nElo: 5.47 +-3.4 (95%) PairsRatio: 1.08

VLTC multicore:
https://tests.stockfishchess.org/tests/view/6272a6afc8f14123163c1997
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 86808 W: 24165 L: 23814 D: 38829
Ptnml(0-2): 11, 7253, 28524, 7606, 10

however, it is now also gaining at LTC:

LTC:
https://tests.stockfishchess.org/tests/view/627e7cb523c0c72a05b651a9
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 27064 W: 7285 L: 7046 D: 12733
Ptnml(0-2): 8, 2446, 8390, 2675, 13

and should have nearly no influence at STC as depth 27 is rarely reached.
It was noticed that initializing the threshold with MAX_PLY, had an adverse effect,
possibly because the first move is sensitive to this.

closes https://github.com/official-stockfish/Stockfish/pull/4021
closes https://github.com/official-stockfish/Stockfish/pull/4016

Bench: 6481017
 2022-05-14 13:17:35 +02:00
Tomasz SobczykandJoost VandeVondele c079acc26f Update NNUE architecture to SFNNv5. Update network to nn-3c0aa92af1da.nnue. 
Architecture changes:

    Duplicated activation after the 1024->15 layer with squared crelu (so 15->15*2). As proposed by vondele.

Trainer changes:

    Added bias to L1 factorization, which was previously missing (no measurable improvement but at least neutral in principle)
    For retraining linearly reduce lambda parameter from 1.0 at epoch 0 to 0.75 at epoch 800.
    reduce max_skipping_rate from 15 to 10 (compared to vondele's outstanding PR)

Note: This network was trained with a ~0.8% error in quantization regarding the newly added activation function.
      This will be fixed in the released trainer version. Expect a trainer PR tomorrow.

Note: The inference implementation cuts a corner to merge results from two activation functions.
       This could possibly be resolved nicer in the future. AVX2 implementation likely not necessary, but NEON is missing.

First training session invocation:

python3 train.py \
    ../nnue-pytorch-training/data/nodes5000pv2_UHO.binpack \
    ../nnue-pytorch-training/data/nodes5000pv2_UHO.binpack \
    --gpus "$3," \
    --threads 4 \
    --num-workers 8 \
    --batch-size 16384 \
    --progress_bar_refresh_rate 20 \
    --random-fen-skipping 3 \
    --features=HalfKAv2_hm^ \
    --lambda=1.0 \
    --max_epochs=400 \
    --default_root_dir ../nnue-pytorch-training/experiment_$1/run_$2

Second training session invocation:

python3 train.py \
    ../nnue-pytorch-training/data/T60T70wIsRightFarseerT60T74T75T76.binpack \
    ../nnue-pytorch-training/data/T60T70wIsRightFarseerT60T74T75T76.binpack \
    --gpus "$3," \
    --threads 4 \
    --num-workers 8 \
    --batch-size 16384 \
    --progress_bar_refresh_rate 20 \
    --random-fen-skipping 3 \
    --features=HalfKAv2_hm^ \
    --start-lambda=1.0 \
    --end-lambda=0.75 \
    --gamma=0.995 \
    --lr=4.375e-4 \
    --max_epochs=800 \
    --resume-from-model /data/sopel/nnue/nnue-pytorch-training/data/exp367/nn-exp367-run3-epoch399.pt \
    --default_root_dir ../nnue-pytorch-training/experiment_$1/run_$2

Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.50>
Total: 27288 W: 7445 L: 7178 D: 12665
Ptnml(0-2): 159, 3002, 7054, 3271, 158
https://tests.stockfishchess.org/tests/view/627e8c001919125939623644

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,3.00>
Total: 21792 W: 5969 L: 5727 D: 10096
Ptnml(0-2): 25, 2152, 6294, 2406, 19
https://tests.stockfishchess.org/tests/view/627f2a855734b18b2e2ece47

closes https://github.com/official-stockfish/Stockfish/pull/4020

Bench: 6481017
 2022-05-14 12:47:22 +02:00
Stéphane Nicolet 9eb7b607cf Reduce depth after score improvement at PV nodes 
STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.50>
Total: 73760 W: 19590 L: 19244 D: 34926
Ptnml(0-2): 285, 8352, 19292, 8634, 317
https://tests.stockfishchess.org/tests/view/626eb2dc9116b52aa83b73da

LTC:
LLR: 2.93 (-2.94,2.94) <0.50,3.00>
Total: 114400 W: 30561 L: 30111 D: 53728
Ptnml(0-2): 68, 11432, 33785, 11812, 103
https://tests.stockfishchess.org/tests/view/626f730859e9c431e0b10b21

closes https://github.com/official-stockfish/Stockfish/pull/4008

bench: 6174823
 2022-05-04 07:47:56 +02:00
candirufishandJoost VandeVondele a32d2086bc Use fail high count for LMR 
Increase reduction if next ply has a lot of fail high else reset count to 0

Passed STC:
https://tests.stockfishchess.org/tests/view/626ea8299116b52aa83b71f6
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 144288 W: 38377 L: 37902 D: 68009
Ptnml(0-2): 565, 16298, 38054, 16551, 676

Passed LTC:
https://tests.stockfishchess.org/tests/view/626fa0fb79f761bab2e382f0
LLR: 2.98 (-2.94,2.94) <0.50,3.00>
Total: 74872 W: 20050 L: 19686 D: 35136
Ptnml(0-2): 51, 7541, 21893, 7895, 56

closes https://github.com/official-stockfish/Stockfish/pull/4006

bench: 7084802
 2022-05-03 17:58:01 +02:00
Stefan GeschwentnerandJoost VandeVondele 285a79eaa0 Simplify time management. 
Replace the best move instability adjustment factor by a simpler version which doesn't have a dependency on the iteration depth.

STC:
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 30800 W: 8232 L: 8073 D: 14495
Ptnml(0-2): 101, 3309, 8444, 3422, 124
https://tests.stockfishchess.org/tests/view/6266c77bc5b924ba22908d30

LTC:
LLR: 2.95 (-2.94,2.94) <-2.25,0.25>
Total: 61664 W: 16375 L: 16272 D: 29017
Ptnml(0-2): 40, 5869, 18897, 6000, 26
https://tests.stockfishchess.org/tests/view/6266fc39b3d1812808915f23

closes https://github.com/official-stockfish/Stockfish/pull/3999

Bench: 7729968
 2022-05-03 17:54:23 +02:00
candirufishandJoost VandeVondele e1f12aa4e6 Negative extension for ttMove that is less than alpha and value 
in the context of singular extensions

Passed STC:
https://tests.stockfishchess.org/tests/view/626047e8b03f22647441ade0
LLR: 2.97 (-2.94,2.94) <0.00,2.50>
Total: 50296 W: 13410 L: 13108 D: 23778
Ptnml(0-2): 196, 5548, 13370, 5826, 208

Passed LTC:
https://tests.stockfishchess.org/tests/view/6260a513b03f22647441b970
LLR: 2.96 (-2.94,2.94) <0.50,3.00>
Total: 83896 W: 22433 L: 22054 D: 39409
Ptnml(0-2): 49, 8273, 24938, 8626, 62

closes https://github.com/official-stockfish/Stockfish/pull/3995

bench: 7729968
 2022-04-22 08:17:22 +02:00
Michael ChalyandJoost VandeVondele e41f727f0f Simplify away best move count logic 
the only place where it was used it was true with >99% probability so it seemed to not be doing much any more.

Passed STC:
https://tests.stockfishchess.org/tests/view/625f4778d00da81c22dd4c93
LLR: 2.95 (-2.94,2.94) <-2.25,0.25>
Total: 85152 W: 22487 L: 22406 D: 40259
Ptnml(0-2): 313, 9035, 23818, 9078, 332

Passed LTC:
https://tests.stockfishchess.org/tests/view/625ff1f1b03f22647441a215
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 66776 W: 17768 L: 17673 D: 31335
Ptnml(0-2): 46, 6200, 20792, 6313, 37

close https://github.com/official-stockfish/Stockfish/pull/3993

bench 7280798
 2022-04-22 08:09:40 +02:00
Joost VandeVondele 6e0680efa0 Update default net to nn-d0b74ce1e5eb.nnue 
train a net using training data with a
heavier weight on positions having 16 pieces on the board. More specifically,
with a relative weight of `i * (32-i)/(16 * 16)+1` (where i is the number of pieces on the board).

This is done with the trainer branch https://github.com/glinscott/nnue-pytorch/pull/173

The command used is:
```
python train.py $datafile $datafile $restarttype $restartfile --gpus 1 --threads 4 --num-workers 12 --random-fen-skipping=3 --batch-size 16384 --progress_bar_refresh_rate 300 --smart-fen-skipping --features=HalfKAv2_hm^   --lambda=1.00  --max_epochs=$epochs --seed $RANDOM --default_root_dir exp/run_$i
```
The datafile is T60T70wIsRightFarseerT60T74T75T76.binpack, the restart is from the master net.

passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 22728 W: 6197 L: 5945 D: 10586
Ptnml(0-2): 105, 2453, 6001, 2695, 110
https://tests.stockfishchess.org/tests/view/625cf944ff677a888877cd90

passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 35664 W: 9535 L: 9264 D: 16865
Ptnml(0-2): 30, 3524, 10455, 3791, 32
https://tests.stockfishchess.org/tests/view/625d3c32ff677a888877d7ca

closes https://github.com/official-stockfish/Stockfish/pull/3989

Bench: 7269563
 2022-04-19 19:59:04 +02:00
Joost VandeVondele c4db7fd1f9 Restore development version 
No functional change.
 2022-04-18 23:05:24 +02:00
Joost VandeVondele e6e324eb28 Stockfish 15 
Official release version of Stockfish 15

Bench: 8129754

---

A new major release of Stockfish is now available at https://stockfishchess.org

Stockfish 15 continues to push the boundaries of chess, providing unrivalled
analysis and playing strength. In our testing, Stockfish 15 is ahead of
Stockfish 14 by 36 Elo points and wins nine times more game pairs than it
loses[1].

Improvements to the engine have made it possible for Stockfish to end up
victorious in tournaments at all sorts of time controls ranging from bullet to
classical and even at Fischer random chess[2]. At CCC, Stockfish won all of
the latest tournaments: CCC 16 Bullet, Blitz and Rapid, CCC 960 championship,
and the CCC 17 Rapid. At TCEC, Stockfish won the Season 21, Cup 9, FRC 4 and
in the current Season 22 superfinal, at the time of writing, has won 16 game
pairs and not yet lost a single one.

This progress is the result of a dedicated team of developers that comes up
with new ideas and improvements. For Stockfish 15, we tested nearly 13000
different changes and retained the best 200. These include the fourth
generation of our NNUE network architecture, as well as various search
improvements. To perform these tests, contributors provide CPU time for
testing, and in the last year, they have collectively played roughly a
billion chess games. In the last few years, our distributed testing
framework, Fishtest, has been operated superbly and has been developed and
improved extensively. This work by Pasquale Pigazzini, Tom Vijlbrief, Michel
Van den Bergh, and various other developers[3] is an essential part of the
success of the Stockfish project.

Indeed, the Stockfish project builds on a thriving community of enthusiasts
to offer a free and open-source chess engine that is robust, widely
available, and very strong. We invite our chess fans to join the Fishtest
testing framework and programmers to contribute to the project[4].

The Stockfish team

[1] https://tests.stockfishchess.org/tests/view/625d156dff677a888877d1be
[2] https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results
[3] https://github.com/glinscott/fishtest/blob/master/AUTHORS
[4] https://stockfishchess.org/get-involved/
sf_15 		2022-04-18 22:03:20 +02:00
KJE-98andJoost VandeVondele df2f7e7527 Decrease LMR at PV nodes with low depth. 
This patch lessens the Late Move Reduction at PV nodes with low depth. Previously the affect of depth on LMR was independant of nodeType. The idea behind this patch is that at PV nodes, LMR at low depth is will miss out on potential alpha-raising moves.

Passed STC:
https://tests.stockfishchess.org/tests/view/625aa867d3367522c4b8965c
LLR: 2.93 (-2.94,2.94) <0.00,2.50>
Total: 19360 W: 5252 L: 5006 D: 9102
Ptnml(0-2): 79, 2113, 5069, 2321, 98

Passed LTC:
https://tests.stockfishchess.org/tests/view/625ae844d3367522c4b8a009
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 39264 W: 10636 L: 10357 D: 18271
Ptnml(0-2): 18, 3928, 11473, 4183, 30

closes https://github.com/official-stockfish/Stockfish/pull/3985

bench: 8129754
 2022-04-17 21:38:05 +02:00
FauziAkramandJoost VandeVondele c25d4c4887 Tuning classical and NNUE scaling terms 
changes to parameters in both classical and NNUE scaling, following up from an earlier successful #3958

passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.50>
Total: 23936 W: 6490 L: 6234 D: 11212
Ptnml(0-2): 107, 2610, 6306, 2810, 135
https://tests.stockfishchess.org/tests/view/625820aa33c40bb9d964e6ae

passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 50376 W: 13629 L: 13327 D: 23420
Ptnml(0-2): 20, 4979, 14920, 5217, 52
https://tests.stockfishchess.org/tests/view/62584592c1d7f5008a33a4d1

closes https://github.com/official-stockfish/Stockfish/pull/3982

Bench: 6964954
 2022-04-16 08:41:51 +02:00
Joost VandeVondele c3b67faf98 Update WDL model for current SF 
This updates the WDL model based on the LTC statistics for the last month (8M games).

for old results see:
https://github.com/official-stockfish/Stockfish/pull/3582
https://github.com/official-stockfish/Stockfish/pull/2778

the model changed a bit from the past, some images to follow in the PR

closes https://github.com/official-stockfish/Stockfish/pull/3981

No functional change.
 2022-04-16 08:36:37 +02:00
Joost VandeVondele 319af5cf0a Update CPU contributors 
closes https://github.com/official-stockfish/Stockfish/pull/3979

No functional change
 2022-04-16 08:35:31 +02:00
TopologistandJoost VandeVondele 19a90b45bc Use NNUE in low piece endgames close to the root. 
This patch enforces that NNUE evaluation is used for endgame positions at shallow depth (depth <= 9).
Classic evaluation will still be used for high imbalance positions when the depth is high or there are many pieces.

Passed STC:
https://tests.stockfishchess.org/tests/view/624c193b3a8a6ac93892dc27
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 255840 W: 68024 L: 67362 D: 120454
Ptnml(0-2): 1074, 27089, 70926, 27763, 1068

Passed LTC:
https://tests.stockfishchess.org/tests/view/624e8675e9e7821808467f77
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 67088 W: 17784 L: 17454 D: 31850
Ptnml(0-2): 45, 6209, 20715, 6521, 54

closes https://github.com/official-stockfish/Stockfish/pull/3978

bench: 6602222
 2022-04-12 17:43:50 +02:00
mstemberaandJoost VandeVondele 9f6bcb38c0 Minor cleanups 
simplify and relocate to position.cpp some of the recent threat calculations used in the movepicker.

passed STC:
https://tests.stockfishchess.org/tests/view/62468c301f682ea45ce3b3b9
LLR: 2.96 (-2.94,2.94) <-2.25,0.25>
Total: 76544 W: 20247 L: 20152 D: 36145
Ptnml(0-2): 327, 8113, 21317, 8168, 347

closes https://github.com/official-stockfish/Stockfish/pull/3972

No functional change
 2022-04-01 10:55:11 +02:00
TopologistandJoost VandeVondele 471d93063a Play more positional in endgames 
This patch chooses the delta value (which skews the nnue evaluation between positional and materialistic)
depending on the material: If the material is low, delta will be higher and the evaluation is shifted
to the positional value. If the material is high, the evaluation will be shifted to the psqt value.
I don't think slightly negative values of delta should be a concern.

Passed STC:
https://tests.stockfishchess.org/tests/view/62418513b3b383e86185766f
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 28808 W: 7832 L: 7564 D: 13412
Ptnml(0-2): 147, 3186, 7505, 3384, 182

Passed LTC:
https://tests.stockfishchess.org/tests/view/62419137b3b383e861857842
LLR: 2.96 (-2.94,2.94) <0.50,3.00>
Total: 58632 W: 15776 L: 15450 D: 27406
Ptnml(0-2): 42, 5889, 17149, 6173, 63

closes https://github.com/official-stockfish/Stockfish/pull/3971

Bench: 7588855
 2022-03-28 22:43:52 +02:00
Michael ChalyandJoost VandeVondele 08e0f52b77 In movepicker increase priority for moves that evade a capture 
This idea is a mix of koivisto idea of threat history and heuristic that
was simplified some time ago in LMR - decreasing reduction for moves that evade a capture.
Instead of doing so in LMR this patch does it in movepicker - to do this it
calculates squares that are attacked by different piece types and pieces that are located
on this squares and boosts up weight of moves that make this pieces land on a square that is not under threat.
Boost is greater for pieces with bigger material values.
Special thanks to koivisto and seer authors for explaining me ideas behind threat history.

Passed STC:
https://tests.stockfishchess.org/tests/view/62406e473b32264b9aa1478b
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 19816 W: 5320 L: 5072 D: 9424
Ptnml(0-2): 86, 2165, 5172, 2385, 100

Passed LTC:
https://tests.stockfishchess.org/tests/view/62407f2e3b32264b9aa149c8
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 51200 W: 13805 L: 13500 D: 23895
Ptnml(0-2): 44, 5023, 15164, 5322, 47

closes https://github.com/official-stockfish/Stockfish/pull/3970

bench 7736491
 2022-03-28 22:37:09 +02:00
Giacomo LorenzettiandJoost VandeVondele 910cf8b218 Remove pos.capture_or_promotion() 
This patch replaces `pos.capture_or_promotion()` with `pos.capture()`
and comes after a few attempts with elo-gaining bounds, two of which
failed yellow at LTC
(https://tests.stockfishchess.org/tests/view/622f8f0cc9e950cbfc237024
and
https://tests.stockfishchess.org/tests/view/62319a8bb3b498ba71a6b2dc).

Passed non-regression STC:
https://tests.stockfishchess.org/tests/view/623aff7eea447151c74828d3
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 246864 W: 65462 L: 65618 D: 115784
Ptnml(0-2): 1201, 28116, 65001, 27866, 1248

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/623c1fdcea447151c7484fb0
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 30120 W: 8125 L: 7978 D: 14017
Ptnml(0-2): 22, 2993, 8881, 3144, 20

closes https://github.com/official-stockfish/Stockfish/pull/3968

Bench: 6847732
 2022-03-25 20:14:00 +01:00
Stefan GeschwentnerandJoost VandeVondele e31f97e3ba Remove ttPv tree shrinking. 
Via the ttPv flag an implicit tree of current and former PV nodes is maintained. In addition this tree is grown or shrinked at the leafs dependant on the search results. But now the shrinking step has been removed.

As the frequency of ttPv nodes decreases with depth the shown scaling behavior (STC barely passed but LTC scales well) of the tests was expected.

STC:
LLR: 2.93 (-2.94,2.94) <-2.25,0.25>
Total: 270408 W: 71593 L: 71785 D: 127030
Ptnml(0-2): 1339, 31024, 70630, 30912, 1299
https://tests.stockfishchess.org/tests/view/622fbf9dc9e950cbfc2376d6

LTC:
LLR: 2.96 (-2.94,2.94) <-2.25,0.25>
Total: 34368 W: 9135 L: 8992 D: 16241
Ptnml(0-2): 28, 3423, 10135, 3574, 24
https://tests.stockfishchess.org/tests/view/62305257c9e950cbfc238964

closes https://github.com/official-stockfish/Stockfish/pull/3963

Bench: 7044203
 2022-03-19 13:40:35 +01:00
mstemberaandStéphane Nicolet f3a2296e59 Small cleanups (2) 
- fix a small compile error under MSVC
- improve sigmoid comment and assert
- fix formatting in README.md

closes https://github.com/official-stockfish/Stockfish/pull/3960

No functional change
 2022-03-13 08:17:02 +01:00
Giacomo LorenzettiandJoost VandeVondele 004ea2c25e Small cleanups 
Delete cast to int in movepick.
update AUTHORS.
adjust assert in sigmoid.
fix spelling mistakes in README

closes https://github.com/official-stockfish/Stockfish/pull/3922
closes https://github.com/official-stockfish/Stockfish/pull/3948
closes https://github.com/official-stockfish/Stockfish/pull/3942

No functional change
 2022-03-12 09:38:34 +01:00
FauziAkramandJoost VandeVondele 45f2416db4 Improvements in Evaluation 
adjust parameters in classical evaluation and NNUE scaling.

STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.50>
Total: 37104 W: 9983 L: 9701 D: 17420
Ptnml(0-2): 154, 4187, 9651, 4343, 217
https://tests.stockfishchess.org/tests/view/6228cb13a9d47c8160e885ba

LTC:
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 266792 W: 71101 L: 70295 D: 125396
Ptnml(0-2): 214, 26928, 78353, 27640, 261
https://tests.stockfishchess.org/tests/view/6228d3c4a9d47c8160e887b0

closes https://github.com/official-stockfish/Stockfish/pull/3958

Bench: 6739741
 2022-03-12 09:25:58 +01:00
Michael ChalyandJoost VandeVondele eae0f8dd06 Decrease reductions in Lmr for some Pv nodes 
This patch makes us reduce less in Lmr at pv nodes in case of static eval being far away from static evaluation of position.
Idea is that if it's the case then probably position is pretty complex so we can't be sure about how reliable LMR is so we need to reduce less.

Passed STC:
https://tests.stockfishchess.org/tests/view/6226276aa9d47c8160e81220
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 262696 W: 69944 L: 69239 D: 123513
Ptnml(0-2): 1399, 29702, 68436, 30417, 1394

Passed LTC:
https://tests.stockfishchess.org/tests/view/6226b002a9d47c8160e82b91
LLR: 2.95 (-2.94,2.94) <0.50,3.00>
Total: 64008 W: 17320 L: 16982 D: 29706
Ptnml(0-2): 60, 6378, 18811, 6674, 81

closes https://github.com/official-stockfish/Stockfish/pull/3957

bench 6678390
 2022-03-08 20:19:42 +01:00
Ben ChaneyandJoost VandeVondele 270a0e737f Generalize the feature transform to use vec_t macros 
This commit generalizes the feature transform to use vec_t macros
that are architecture defined instead of using a seperate code path for each one.

It should make some old architectures (MMX, including improvements by Fanael) faster
and make further such improvements easier in the future.

Includes some corrections to CI for mingw.

closes https://github.com/official-stockfish/Stockfish/pull/3955
closes https://github.com/official-stockfish/Stockfish/pull/3928

No functional change
 2022-03-02 23:39:08 +01:00
Giacomo LorenzettiandJoost VandeVondele 4ac7d726ec Sort captures 
This patch (partially) sort captures in analogy to quiet moves. All
three movepickers are affected, hence `depth` is added as an argument in
probcut's.

Passed STC:
https://tests.stockfishchess.org/tests/view/621a4576da649bba32ef6fd4
LLR: 2.95 (-2.94,2.94) <0.00,2.50>
Total: 103848 W: 27884 L: 27473 D: 48491
Ptnml(0-2): 587, 11691, 26974, 12068, 604

Passed LTC:
https://tests.stockfishchess.org/tests/view/621aaa5bda649bba32ef7c2d
LLR: 2.96 (-2.94,2.94) <0.50,3.00>
Total: 212032 W: 56420 L: 55739 D: 99873
Ptnml(0-2): 198, 21310, 62348, 21933, 227

closes https://github.com/official-stockfish/Stockfish/pull/3952

Bench: 6833580
 2022-03-01 17:51:37 +01:00
Tomasz SobczykandJoost VandeVondele 174b038bf3 Use dynamic allocation for evaluation scratch TLS buffer. 
fixes #3946 an issue related with the toolchain as found in xcode 12 on macOS,
related to previous commit 5f781d36.

closes https://github.com/official-stockfish/Stockfish/pull/3950

No functional change
 2022-03-01 17:51:02 +01:00
mstemberaandJoost VandeVondele 5f781d366e Clean up and simplify some nnue code. 
Remove some unnecessary code and it's execution during inference. Also the change on line 49 in nnue_architecture.h results in a more efficient SIMD code path through ClippedReLU::propagate().

passed STC:
https://tests.stockfishchess.org/tests/view/6217d3bfda649bba32ef25d5
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 12056 W: 3281 L: 3092 D: 5683
Ptnml(0-2): 55, 1213, 3312, 1384, 64

passed STC SMP:
https://tests.stockfishchess.org/tests/view/6217f344da649bba32ef295e
LLR: 2.94 (-2.94,2.94) <-2.25,0.25>
Total: 27376 W: 7295 L: 7137 D: 12944
Ptnml(0-2): 52, 2859, 7715, 3003, 59

closes https://github.com/official-stockfish/Stockfish/pull/3944

No functional change

bench: 6820724
 2022-02-25 08:37:57 +01:00
Michael ChalyandJoost VandeVondele 27139dedac Adjust usage of LMR for 2nd move in move ordering 
Current master prohibits usage of LMR for 2nd move at rootNode. This patch also disables LMR for 2nd move not only at rootNode but also at first PvNode that is a reply to rootNode.

passed STC:
https://tests.stockfishchess.org/tests/view/620e8c9026f5b17ec885143a
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 54096 W: 14305 L: 13996 D: 25795
Ptnml(0-2): 209, 6075, 14192, 6342, 230

passed LTC:
https://tests.stockfishchess.org/tests/view/620eb327b1792e8985f81fb8
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 110864 W: 29602 L: 29156 D: 52106
Ptnml(0-2): 112, 11147, 32455, 11619, 99

closes https://github.com/official-stockfish/Stockfish/pull/3940

bench 6820724
 2022-02-20 23:01:22 +01:00
Joost VandeVondele abef3e86f4 Fix clang warning on unused variable 
mark variable as used.

fixes https://github.com/official-stockfish/Stockfish/issues/3900
closes https://github.com/official-stockfish/Stockfish/pull/3941

No functional change
 2022-02-20 22:59:19 +01:00
ppigazziniandJoost VandeVondele 2da1d1bf57 Add ARM NDK to Github Actions matrix 
- set the variable only for the required tests to keep simple the yml file
- use NDK 21.x until will be fixed the Stockfish static build problem
  with NDK 23.x
- set the test for armv7, armv7-neon, armv8 builds:
  - use armv7a-linux-androideabi21-clang++ compiler for armv7 armv7-neon
  - enforce a static build
  - silence the Warning for the unused compilation flag "-pie" with
    the static build, otherwise the Github workflow stops
  - use qemu to bench the build and get the signature

Many thanks to @pschneider1968 that made all the hard work with NDK :)

closes https://github.com/official-stockfish/Stockfish/pull/3924

No functional change
 2022-02-20 22:56:11 +01:00