Less aggressive move count based futility pruning
authorJoona Kiiski <joona.kiiski@gmail.com>
Sat, 3 Jul 2010 21:38:49 +0000 (00:38 +0300)
committerMarco Costalba <mcostalba@gmail.com>
Sun, 26 Sep 2010 09:27:15 +0000 (10:27 +0100)
commit3fd00798074485dfa56d283136d809b7c8bff35a
tree5b6982b1b8f8325d2e3e2c2cb119e7f15cc1e558
parenta28f4a56d31c9e7f7c5ce28a93e2b2b9ca9be5e5
Less aggressive move count based futility pruning

This patch from Joona greatly reduces move count pruning,
below is the old and new move count limits starting from
ONE_PLY with half-play increment:

Old: 4,5,5,5, 7, 7,11,11,11,19,19,19,35,35
New: 4,5,7,9,12,15,19,23,28,33,39,45,52,59

Surprisingly results are even a bit better at a quite
fast time control.

After 5260 games at 30"+0.1
Mod - Orig:  864 - 806 - 3590  ELO +3 (+- 3.8)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
src/search.cpp