The idea is to use NNUE only on quite balanced material positions. This bring a big speedup on research since NNUE eval is slower than classical eval for most of the hardwares and specially on unbalanced positions with LazyEval.
STC: https://tests.stockfishchess.org/tests/view/
5f2c2680b3ebe5cbfee85b61
LLR: 2.95 (-2.94,2.94) {-0.50,1.50}
Total: 3168 W: 560 L: 400 D: 2208
Ptnml(0-2): 21, 294, 819, 404, 46
LTC: https://tests.stockfishchess.org/tests/view/
5f2c2ca6b3ebe5cbfee85b69
LLR: 2.98 (-2.94,2.94) {0.25,1.75}
Total: 3200 W: 287 L: 183 D: 2730
Ptnml(0-2): 4, 149, 1191, 251, 5
closes https://github.com/official-stockfish/Stockfish/pull/2916
Bench
4746616
namespace {
// Threshold for lazy and space evaluation
namespace {
// Threshold for lazy and space evaluation
- constexpr Value LazyThreshold1 = Value(1400);
- constexpr Value LazyThreshold2 = Value(1300);
+ constexpr Value LazyThreshold1 = Value(1400);
+ constexpr Value LazyThreshold2 = Value(1300);
constexpr Value SpaceThreshold = Value(12222);
constexpr Value SpaceThreshold = Value(12222);
+ constexpr Value NNUEThreshold = Value(500);
// KingAttackWeights[PieceType] contains king attack weights by piece type
constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
// KingAttackWeights[PieceType] contains king attack weights by piece type
constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
Value Eval::evaluate(const Position& pos) {
if (Eval::useNNUE)
Value Eval::evaluate(const Position& pos) {
if (Eval::useNNUE)
- return NNUE::evaluate(pos);
- else
- return Evaluation<NO_TRACE>(pos).value();
+ {
+ Value balance = pos.non_pawn_material(WHITE) - pos.non_pawn_material(BLACK);
+ balance += 200 * (pos.count<PAWN>(WHITE) - pos.count<PAWN>(BLACK));
+ // Take NNUE eval only on balanced positions
+ if (abs(balance) < NNUEThreshold)
+ return NNUE::evaluate(pos);
+ }
+ return Evaluation<NO_TRACE>(pos).value();
}
/// trace() is like evaluate(), but instead of returning a value, it returns
}
/// trace() is like evaluate(), but instead of returning a value, it returns