Dev Builds » 20251221-1443

Use this dev build

NCM plays each Stockfish dev build 20,000 times against Stockfish 15. This yields an approximate Elo difference and establishes confidence in the strength of the dev builds.

Summary

Host Duration Avg Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo
ncm-dbt-01 06:46:00 580824 4000 1693 391 1916 +117.36 ± 4.57 0 40 639 1300 21 +263.71 ± 13.44
ncm-dbt-02 06:45:47 586865 4014 1726 370 1918 +122.17 ± 4.58 1 39 594 1349 24 +278.03 ± 13.96
ncm-dbt-03 06:44:46 585714 3994 1712 393 1889 +119.21 ± 4.58 0 33 641 1294 29 +266.95 ± 13.39
ncm-dbt-04 06:45:53 565193 4002 1716 423 1863 +116.42 ± 4.63 0 43 647 1286 25 +259.72 ± 13.36
ncm-dbt-05 06:46:24 581596 3990 1719 393 1878 +120.02 ± 4.66 2 35 624 1303 31 +269.44 ± 13.6
20000 8566 1970 9464 +119.03 ± 2.06 3 190 3145 6532 130 +267.51 ± 6.05

Test Detail

ID Host Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo CLI PGN
446824 ncm-dbt-04 566612 2 1 0 1 +189.7 ± 55.98 0 0 0 1 0 +1129.65 ± 376.02
446823 ncm-dbt-02 585590 14 7 4 3 +75.56 ± 67.89 0 0 4 3 0 +159.09 ± 177.81
446822 ncm-dbt-03 583824 494 213 50 231 +119.09 ± 12.9 0 4 79 161 3 +268.03 ± 38.46
446821 ncm-dbt-05 582277 490 206 55 229 +110.66 ± 14.41 1 8 79 153 4 +243.05 ± 38.63
446820 ncm-dbt-01 579620 500 220 44 236 +127.76 ± 11.86 0 2 71 176 1 +301.33 ± 40.6
446819 ncm-dbt-02 585464 500 216 39 245 +128.55 ± 11.83 0 0 76 171 3 +298.62 ± 38.82
446818 ncm-dbt-04 566178 500 219 52 229 +120.67 ± 12.02 0 2 80 167 1 +277.93 ± 38.02
446817 ncm-dbt-03 585590 500 215 46 239 +122.24 ± 12.76 0 4 76 167 3 +277.93 ± 39.29
446816 ncm-dbt-05 579826 500 217 49 234 +121.46 ± 12.95 1 3 75 169 2 +280.42 ± 39.57
446815 ncm-dbt-01 583572 500 208 57 235 +108.3 ± 12.53 0 5 89 156 0 +243.0 ± 36.1
446814 ncm-dbt-04 565666 500 218 47 235 +123.81 ± 13.1 0 5 73 168 4 +280.42 ± 40.21
446813 ncm-dbt-02 586943 500 213 42 245 +123.81 ± 13.1 0 6 70 171 3 +282.94 ± 41.13
446812 ncm-dbt-01 581194 500 210 55 235 +111.37 ± 13.22 0 3 95 146 6 +238.66 ± 34.61
446811 ncm-dbt-03 588472 500 222 51 227 +123.81 ± 12.92 0 5 72 170 3 +282.94 ± 40.5
446810 ncm-dbt-05 581070 500 209 50 241 +114.45 ± 12.85 0 7 77 166 0 +261.07 ± 39.14
446809 ncm-dbt-02 587409 500 219 48 233 +123.81 ± 12.54 0 5 70 174 1 +288.06 ± 41.11
446808 ncm-dbt-04 566691 500 212 56 232 +112.14 ± 13.04 0 5 87 155 3 +247.41 ± 36.56
446807 ncm-dbt-03 585759 500 206 57 237 +106.77 ± 13.39 0 4 99 141 6 +226.0 ± 33.89
446806 ncm-dbt-01 581485 500 213 36 251 +128.55 ± 11.63 0 1 72 176 1 +304.07 ± 40.16
446805 ncm-dbt-05 584453 500 214 48 238 +119.89 ± 12.79 0 3 82 161 4 +268.17 ± 37.61
446804 ncm-dbt-02 587579 500 213 50 237 +117.55 ± 13.7 1 5 78 162 4 +263.42 ± 38.85
446803 ncm-dbt-04 563587 500 218 45 237 +125.38 ± 12.7 0 3 75 168 4 +285.49 ± 39.5
446802 ncm-dbt-03 585548 500 207 49 244 +113.68 ± 13.21 0 6 83 158 3 +251.89 ± 37.57
446801 ncm-dbt-01 580530 500 203 44 253 +114.45 ± 12.49 0 2 90 155 3 +254.16 ± 35.58
446800 ncm-dbt-05 582652 500 212 44 244 +121.45 ± 13.84 0 5 80 157 8 +263.42 ± 38.27
446799 ncm-dbt-02 586604 500 213 37 250 +127.76 ± 12.26 0 1 76 169 4 +293.29 ± 38.98
446798 ncm-dbt-04 562612 500 209 56 235 +109.83 ± 14.69 0 12 79 153 6 +234.38 ± 38.61
446797 ncm-dbt-03 584327 500 217 48 235 +122.24 ± 12.57 0 2 81 163 4 +275.45 ± 37.75
446796 ncm-dbt-01 579702 500 213 52 235 +116.0 ± 14.05 0 11 70 166 3 +258.75 ± 41.02
446795 ncm-dbt-05 584369 500 219 54 227 +119.11 ± 13.17 0 4 82 159 5 +263.42 ± 37.69
446794 ncm-dbt-02 589326 500 211 42 247 +122.24 ± 12.94 0 6 71 171 2 +280.42 ± 40.83
446793 ncm-dbt-04 565430 500 217 53 230 +118.33 ± 12.81 0 4 81 162 3 +265.78 ± 37.95
446792 ncm-dbt-03 586901 500 215 50 235 +119.11 ± 13.34 0 6 77 163 4 +265.78 ± 39.12
446791 ncm-dbt-01 581777 500 213 49 238 +118.33 ± 13.17 0 6 77 164 3 +265.78 ± 39.12
446790 ncm-dbt-05 577971 500 228 54 218 +126.17 ± 12.68 0 2 77 166 5 +285.49 ± 38.83
446789 ncm-dbt-02 585928 500 212 52 236 +115.22 ± 14.05 0 10 74 162 4 +254.16 ± 39.94
446788 ncm-dbt-04 563041 500 211 57 232 +110.6 ± 12.88 0 5 88 155 2 +245.2 ± 36.32
446787 ncm-dbt-03 585295 500 217 42 241 +126.97 ± 12.28 0 2 74 171 3 +293.29 ± 39.69
446786 ncm-dbt-01 578712 500 213 54 233 +114.45 ± 14.05 0 10 75 161 4 +251.89 ± 39.67
446785 ncm-dbt-02 586943 500 222 56 222 +119.89 ± 13.16 0 6 75 166 3 +270.57 ± 39.67
446784 ncm-dbt-05 580157 500 214 39 247 +126.97 ± 12.47 0 3 72 172 3 +293.29 ± 40.39
446783 ncm-dbt-04 566928 500 211 57 232 +110.6 ± 13.22 0 7 84 157 2 +245.2 ± 37.37

Commit

Commit ID e0e6fdf094d7b34750f99d3603943349ab7a57e9
Author Timothy Herchen
Date 2025-12-21 14:43:32 UTC
Tweak nnue_accumulator indexing ``` LLR: 2.93 (-2.94,2.94) <0.00,2.00> Total: 92736 W: 24149 L: 23764 D: 44823 Ptnml(0-2): 280, 10056, 25334, 10395, 303 ``` The use of `IndexType` in the loops is suboptimal because it requires truncation to 32 bits, and thereby defeats some optimizations. Using `size_t` for the loop body works nicely, and a signed index into the index lists allows the compiler to assume the case `added.size() == UINT_MAX`, which would be an infinite loop, to not happen. Passed STC https://tests.stockfishchess.org/tests/live_elo/692fd98ab23dfeae38d01d98 closes https://github.com/official-stockfish/Stockfish/pull/6466 No functional change
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