Do more reductions at Pv nodes with low delta
authorMichael Chaly <Vizvezdenec@gmail.com>
Thu, 4 Nov 2021 15:35:01 +0000 (18:35 +0300)
committerJoost VandeVondele <Joost.VandeVondele@gmail.com>
Fri, 5 Nov 2021 21:18:59 +0000 (22:18 +0100)
commitc2b9134c6e7637ea375b4755a6f96dc772c6bb17
tree23343a6ff0d23fd53b237c23d2464ba28e8a37a8
parent11c6cf720d4cdd882bc0f2c36e25910cf77fb57b
Do more reductions at Pv nodes with low delta

This patch increases reduction for PvNodes that have their delta (difference between beta and alpha) significantly reduced compared to what it was at root.

passed STC
https://tests.stockfishchess.org/tests/view/617f9063af49befdeee40226
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 220840 W: 55752 L: 55150 D: 109938
Ptnml(0-2): 583, 24982, 58712, 25536, 607

passed LTC
https://tests.stockfishchess.org/tests/view/61815de959e71df00dcc42ed
LLR: 2.95 (-2.94,2.94) <0.50,3.00>
Total: 79000 W: 19937 L: 19562 D: 39501
Ptnml(0-2): 36, 8190, 22674, 8563, 37

closes https://github.com/official-stockfish/Stockfish/pull/3774

bench: 6717808
src/search.cpp
src/thread.h