From 29ed22de8cd347cacb0ba826ee43fa587985a98d Mon Sep 17 00:00:00 2001 From: bmc4 Date: Thu, 4 Feb 2021 21:50:22 -0300 Subject: [PATCH] Search Parameters Tuning A simple tuning on search.cpp. based SPSA test: https://tests.stockfishchess.org/tests/view/601f2a787f517a561bc493cd passed STC: LLR: 2.94 (-2.94,2.94) {-0.25,1.25} Total: 117840 W: 10796 L: 10508 D: 96536 Ptnml(0-2): 422, 8381, 41041, 8639, 437 https://tests.stockfishchess.org/tests/view/602144c37f517a561bc494ae passed LTC: LLR: 2.96 (-2.94,2.94) {0.25,1.25} Total: 25024 W: 972 L: 847 D: 23205 Ptnml(0-2): 7, 767, 10847, 876, 15 https://tests.stockfishchess.org/tests/view/602156877f517a561bc494be closes https://github.com/official-stockfish/Stockfish/pull/3340 Bench: 3974098 --- src/search.cpp | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index 6cc115fc..80c3e4c2 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -81,7 +81,7 @@ namespace { // History and stats update bonus, based on depth int stat_bonus(Depth d) { - return d > 14 ? 29 : 8 * d * d + 224 * d - 215; + return d > 14 ? 66 : 6 * d * d + 231 * d - 206; } // Add a small random component to draw evaluations to avoid 3-fold blindness @@ -839,10 +839,10 @@ namespace { // Step 8. Null move search with verification search (~40 Elo) if ( !PvNode && (ss-1)->currentMove != MOVE_NULL - && (ss-1)->statScore < 22977 + && (ss-1)->statScore < 22661 && eval >= beta && eval >= ss->staticEval - && ss->staticEval >= beta - 30 * depth - 28 * improving + 84 * ss->ttPv + 168 + && ss->staticEval >= beta - 24 * depth - 34 * improving + 162 * ss->ttPv + 159 && !excludedMove && pos.non_pawn_material(us) && (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor)) @@ -850,7 +850,7 @@ namespace { assert(eval - beta >= 0); // Null move dynamic reduction based on depth and value - Depth R = (1015 + 85 * depth) / 256 + std::min(int(eval - beta) / 191, 3); + Depth R = (1062 + 68 * depth) / 256 + std::min(int(eval - beta) / 190, 3); ss->currentMove = MOVE_NULL; ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0]; @@ -886,7 +886,7 @@ namespace { } } - probCutBeta = beta + 194 - 49 * improving; + probCutBeta = beta + 209 - 44 * improving; // Step 9. ProbCut (~10 Elo) // If we have a good enough capture and a reduced search returns a value @@ -1063,11 +1063,11 @@ moves_loop: // When in check, search starts from here // Futility pruning: parent node (~5 Elo) if ( lmrDepth < 7 && !ss->inCheck - && ss->staticEval + 254 + 159 * lmrDepth <= alpha + && ss->staticEval + 174 + 157 * lmrDepth <= alpha && (*contHist[0])[movedPiece][to_sq(move)] + (*contHist[1])[movedPiece][to_sq(move)] + (*contHist[3])[movedPiece][to_sq(move)] - + (*contHist[5])[movedPiece][to_sq(move)] / 2 < 26394) + + (*contHist[5])[movedPiece][to_sq(move)] / 3 < 26237) continue; // Prune moves with negative SEE (~20 Elo) @@ -1223,13 +1223,13 @@ moves_loop: // When in check, search starts from here + (*contHist[0])[movedPiece][to_sq(move)] + (*contHist[1])[movedPiece][to_sq(move)] + (*contHist[3])[movedPiece][to_sq(move)] - - 5287; + - 5337; // Decrease/increase reduction by comparing opponent's stat score (~10 Elo) - if (ss->statScore >= -105 && (ss-1)->statScore < -103) + if (ss->statScore >= -89 && (ss-1)->statScore < -116) r--; - else if ((ss-1)->statScore >= -122 && ss->statScore < -129) + else if ((ss-1)->statScore >= -112 && ss->statScore < -100) r++; // Decrease/increase reduction for moves with a good/bad history (~30 Elo) @@ -1237,9 +1237,9 @@ moves_loop: // When in check, search starts from here // use sum of main history and first continuation history with an offset if (ss->inCheck) r -= (thisThread->mainHistory[us][from_to(move)] - + (*contHist[0])[movedPiece][to_sq(move)] - 4333) / 16384; + + (*contHist[0])[movedPiece][to_sq(move)] - 4341) / 16384; else - r -= ss->statScore / 14884; + r -= ss->statScore / 14382; } Depth d = std::clamp(newDepth - r, 1, newDepth); @@ -1711,8 +1711,8 @@ moves_loop: // When in check, search starts from here PieceType captured = type_of(pos.piece_on(to_sq(bestMove))); bonus1 = stat_bonus(depth + 1); - bonus2 = bestValue > beta + PawnValueMg ? bonus1 // larger bonus - : stat_bonus(depth); // smaller bonus + bonus2 = bestValue > beta + PawnValueMg ? bonus1 // larger bonus + : std::min(bonus1, stat_bonus(depth)); // smaller bonus if (!pos.capture_or_promotion(bestMove)) { -- 2.39.2