From 61acbfc7d310ed6044ba4fc5ef91a6c382d1c9a6 Mon Sep 17 00:00:00 2001 From: Muzhen Gaming <61100393+XInTheDark@users.noreply.github.com> Date: Thu, 23 May 2024 08:28:46 +0800 Subject: [PATCH] VVLTC search tune Parameters were tuned in 2 stages: 1. 127k games at VVLTC: https://tests.stockfishchess.org/tests/view/6649f8dfb8fa20e74c39f52a. 2. 106k games at VVLTC: https://tests.stockfishchess.org/tests/view/664bfb77830eb9f886615a9d. Passed VVLTC 1st sprt: https://tests.stockfishchess.org/tests/view/664e8dd9928b1fb18de4e410 LLR: 2.94 (-2.94,2.94) <0.00,2.00> Total: 20466 W: 5340 L: 5093 D: 10033 Ptnml(0-2): 0, 1796, 6397, 2037, 3 Passed VVLTC 2nd sprt: https://tests.stockfishchess.org/tests/view/664eb4aa928b1fb18de4e47d LLR: 2.95 (-2.94,2.94) <0.50,2.50> Total: 15854 W: 4186 L: 3934 D: 7734 Ptnml(0-2): 1, 1367, 4938, 1621, 0 closes https://github.com/official-stockfish/Stockfish/pull/5286 Bench: 1558110 --- src/search.cpp | 88 +++++++++++++++++++++++++------------------------- 1 file changed, 44 insertions(+), 44 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index 477667306ad..563a5710f89 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -60,9 +60,9 @@ static constexpr double EvalLevel[10] = {0.981, 0.956, 0.895, 0.949, 0.913, // Futility margin Value futility_margin(Depth d, bool noTtCutNode, bool improving, bool oppWorsening) { - Value futilityMult = 127 - 48 * noTtCutNode; - Value improvingDeduction = 65 * improving * futilityMult / 32; - Value worseningDeduction = 334 * oppWorsening * futilityMult / 1024; + Value futilityMult = 129 - 43 * noTtCutNode; + Value improvingDeduction = 56 * improving * futilityMult / 32; + Value worseningDeduction = 336 * oppWorsening * futilityMult / 1024; return futilityMult * d - improvingDeduction - worseningDeduction; } @@ -74,15 +74,15 @@ constexpr int futility_move_count(bool improving, Depth depth) { // Add correctionHistory value to raw staticEval and guarantee evaluation does not hit the tablebase range Value to_corrected_static_eval(Value v, const Worker& w, const Position& pos) { auto cv = w.correctionHistory[pos.side_to_move()][pawn_structure_index(pos)]; - v += cv * std::abs(cv) / 6047; + v += cv * std::abs(cv) / 5435; return std::clamp(v, VALUE_TB_LOSS_IN_MAX_PLY + 1, VALUE_TB_WIN_IN_MAX_PLY - 1); } // History and stats update bonus, based on depth -int stat_bonus(Depth d) { return std::clamp(187 * d - 288, 17, 1548); } +int stat_bonus(Depth d) { return std::clamp(205 * d - 283, 18, 1544); } // History and stats update malus, based on depth -int stat_malus(Depth d) { return (d < 4 ? 630 * d - 281 : 1741); } +int stat_malus(Depth d) { return (d < 4 ? 767 * d - 275 : 1911); } // Add a small random component to draw evaluations to avoid 3-fold blindness Value value_draw(size_t nodes) { return VALUE_DRAW - 1 + Value(nodes & 0x2); } @@ -312,12 +312,12 @@ void Search::Worker::iterative_deepening() { // Reset aspiration window starting size Value avg = rootMoves[pvIdx].averageScore; - delta = 10 + avg * avg / 9828; + delta = 9 + avg * avg / 10502; alpha = std::max(avg - delta, -VALUE_INFINITE); beta = std::min(avg + delta, VALUE_INFINITE); // Adjust optimism based on root move's averageScore (~4 Elo) - optimism[us] = 116 * avg / (std::abs(avg) + 84); + optimism[us] = 122 * avg / (std::abs(avg) + 92); optimism[~us] = -optimism[us]; // Start with a small aspiration window and, in the case of a fail @@ -507,7 +507,7 @@ void Search::Worker::clear() { h->fill(-60); for (size_t i = 1; i < reductions.size(); ++i) - reductions[i] = int((21.69 + std::log(size_t(options["Threads"])) / 2) * std::log(i)); + reductions[i] = int((19.90 + std::log(size_t(options["Threads"])) / 2) * std::log(i)); refreshTable.clear(networks); } @@ -740,7 +740,7 @@ Value Search::Worker::search( // Use static evaluation difference to improve quiet move ordering (~9 Elo) if (((ss - 1)->currentMove).is_ok() && !(ss - 1)->inCheck && !priorCapture) { - int bonus = std::clamp(-11 * int((ss - 1)->staticEval + ss->staticEval), -1729, 1517); + int bonus = std::clamp(-11 * int((ss - 1)->staticEval + ss->staticEval), -1592, 1390); bonus = bonus > 0 ? 2 * bonus : bonus / 2; thisThread->mainHistory[~us][((ss - 1)->currentMove).from_to()] << bonus; if (type_of(pos.piece_on(prevSq)) != PAWN && ((ss - 1)->currentMove).type_of() != PROMOTION) @@ -762,7 +762,7 @@ Value Search::Worker::search( // Step 7. Razoring (~1 Elo) // If eval is really low check with qsearch if it can exceed alpha, if it can't, // return a fail low. - if (eval < alpha - 474 - 324 * depth * depth) + if (eval < alpha - 501 - 305 * depth * depth) { value = qsearch(pos, ss, alpha - 1, alpha); if (value < alpha) @@ -771,23 +771,23 @@ Value Search::Worker::search( // Step 8. Futility pruning: child node (~40 Elo) // The depth condition is important for mate finding. - if (!ss->ttPv && depth < 11 + if (!ss->ttPv && depth < 12 && eval - futility_margin(depth, cutNode && !ss->ttHit, improving, opponentWorsening) - - (ss - 1)->statScore / 252 + - (ss - 1)->statScore / 248 >= beta && eval >= beta && eval < VALUE_TB_WIN_IN_MAX_PLY && (!ttMove || ttCapture)) return beta > VALUE_TB_LOSS_IN_MAX_PLY ? (eval + beta) / 2 : eval; // Step 9. Null move search with verification search (~35 Elo) - if (!PvNode && (ss - 1)->currentMove != Move::null() && (ss - 1)->statScore < 15246 - && eval >= beta && ss->staticEval >= beta - 21 * depth + 366 && !excludedMove + if (!PvNode && (ss - 1)->currentMove != Move::null() && (ss - 1)->statScore < 13999 + && eval >= beta && ss->staticEval >= beta - 21 * depth + 390 && !excludedMove && pos.non_pawn_material(us) && ss->ply >= thisThread->nmpMinPly && beta > VALUE_TB_LOSS_IN_MAX_PLY) { assert(eval - beta >= 0); // Null move dynamic reduction based on depth and eval - Depth R = std::min(int(eval - beta) / 152, 6) + depth / 3 + 5; + Depth R = std::min(int(eval - beta) / 177, 6) + depth / 3 + 5; ss->currentMove = Move::null(); ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0]; @@ -845,7 +845,7 @@ Value Search::Worker::search( // Step 11. ProbCut (~10 Elo) // If we have a good enough capture (or queen promotion) and a reduced search returns a value // much above beta, we can (almost) safely prune the previous move. - probCutBeta = beta + 176 - 65 * improving; + probCutBeta = beta + 185 - 60 * improving; if ( !PvNode && depth > 3 && std::abs(beta) < VALUE_TB_WIN_IN_MAX_PLY @@ -901,7 +901,7 @@ Value Search::Worker::search( moves_loop: // When in check, search starts here // Step 12. A small Probcut idea, when we are in check (~4 Elo) - probCutBeta = beta + 440; + probCutBeta = beta + 361; if (ss->inCheck && !PvNode && ttCapture && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 4 && ttValue >= probCutBeta && std::abs(ttValue) < VALUE_TB_WIN_IN_MAX_PLY && std::abs(beta) < VALUE_TB_WIN_IN_MAX_PLY) @@ -985,15 +985,15 @@ Value Search::Worker::search( // Futility pruning for captures (~2 Elo) if (!givesCheck && lmrDepth < 7 && !ss->inCheck) { - Value futilityValue = ss->staticEval + 276 + 256 * lmrDepth + Value futilityValue = ss->staticEval + 283 + 235 * lmrDepth + PieceValue[capturedPiece] + captHist / 7; if (futilityValue <= alpha) continue; } // SEE based pruning for captures and checks (~11 Elo) - int seeHist = std::clamp(captHist / 32, -177 * depth, 175 * depth); - if (!pos.see_ge(move, -183 * depth - seeHist)) + int seeHist = std::clamp(captHist / 32, -183 * depth, 162 * depth); + if (!pos.see_ge(move, -166 * depth - seeHist)) continue; } else @@ -1004,18 +1004,18 @@ Value Search::Worker::search( + thisThread->pawnHistory[pawn_structure_index(pos)][movedPiece][move.to_sq()]; // Continuation history based pruning (~2 Elo) - if (lmrDepth < 6 && history < -4076 * depth) + if (lmrDepth < 6 && history < -4427 * depth) continue; history += 2 * thisThread->mainHistory[us][move.from_to()]; - lmrDepth += history / 4401; + lmrDepth += history / 3670; Value futilityValue = - ss->staticEval + (bestValue < ss->staticEval - 53 ? 151 : 57) + 140 * lmrDepth; + ss->staticEval + (bestValue < ss->staticEval - 51 ? 149 : 55) + 141 * lmrDepth; // Futility pruning: parent node (~13 Elo) - if (!ss->inCheck && lmrDepth < 10 && futilityValue <= alpha) + if (!ss->inCheck && lmrDepth < 11 && futilityValue <= alpha) { if (bestValue <= futilityValue && std::abs(bestValue) < VALUE_TB_WIN_IN_MAX_PLY && futilityValue < VALUE_TB_WIN_IN_MAX_PLY) @@ -1049,11 +1049,11 @@ Value Search::Worker::search( // margins scale well. if (!rootNode && move == ttMove && !excludedMove - && depth >= 4 - (thisThread->completedDepth > 35) + ss->ttPv + && depth >= 4 - (thisThread->completedDepth > 38) + ss->ttPv && std::abs(ttValue) < VALUE_TB_WIN_IN_MAX_PLY && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 3) { - Value singularBeta = ttValue - (57 + 50 * (ss->ttPv && !PvNode)) * depth / 64; + Value singularBeta = ttValue - (58 + 64 * (ss->ttPv && !PvNode)) * depth / 64; Depth singularDepth = newDepth / 2; ss->excludedMove = move; @@ -1063,15 +1063,15 @@ Value Search::Worker::search( if (value < singularBeta) { - int doubleMargin = 298 * PvNode - 209 * !ttCapture; - int tripleMargin = 117 + 252 * PvNode - 270 * !ttCapture + 111 * ss->ttPv; - int quadMargin = 471 + 343 * PvNode - 281 * !ttCapture + 217 * ss->ttPv; + int doubleMargin = 304 * PvNode - 203 * !ttCapture; + int tripleMargin = 117 + 259 * PvNode - 296 * !ttCapture + 97 * ss->ttPv; + int quadMargin = 486 + 343 * PvNode - 273 * !ttCapture + 232 * ss->ttPv; extension = 1 + (value < singularBeta - doubleMargin) + (value < singularBeta - tripleMargin) + (value < singularBeta - quadMargin); - depth += ((!PvNode) && (depth < 15)); + depth += ((!PvNode) && (depth < 16)); } // Multi-cut pruning @@ -1101,7 +1101,7 @@ Value Search::Worker::search( else if (PvNode && move == ttMove && move.to_sq() == prevSq && thisThread->captureHistory[movedPiece][move.to_sq()] [type_of(pos.piece_on(move.to_sq()))] - > 3748) + > 3988) extension = 1; } @@ -1157,10 +1157,10 @@ Value Search::Worker::search( ss->statScore = 2 * thisThread->mainHistory[us][move.from_to()] + (*contHist[0])[movedPiece][move.to_sq()] - + (*contHist[1])[movedPiece][move.to_sq()] - 5266; + + (*contHist[1])[movedPiece][move.to_sq()] - 5169; // Decrease/increase reduction for moves with a good/bad history (~8 Elo) - r -= ss->statScore / (14519 - std::min(depth, 15) * 103); + r -= ss->statScore / (12219 - std::min(depth, 13) * 120); // Step 17. Late moves reduction / extension (LMR, ~117 Elo) if (depth >= 2 && moveCount > 1 + rootNode) @@ -1179,7 +1179,7 @@ Value Search::Worker::search( { // Adjust full-depth search based on LMR results - if the result // was good enough search deeper, if it was bad enough search shallower. - const bool doDeeperSearch = value > (bestValue + 40 + 2 * newDepth); // (~1 Elo) + const bool doDeeperSearch = value > (bestValue + 36 + 2 * newDepth); // (~1 Elo) const bool doShallowerSearch = value < bestValue + newDepth; // (~2 Elo) newDepth += doDeeperSearch - doShallowerSearch; @@ -1340,9 +1340,9 @@ Value Search::Worker::search( // Bonus for prior countermove that caused the fail low else if (!priorCapture && prevSq != SQ_NONE) { - int bonus = (depth > 4) + (depth > 5) + (PvNode || cutNode) + ((ss - 1)->statScore < -13241) - + ((ss - 1)->moveCount > 10) + (!ss->inCheck && bestValue <= ss->staticEval - 127) - + (!(ss - 1)->inCheck && bestValue <= -(ss - 1)->staticEval - 74); + int bonus = (depth > 4) + (depth > 5) + (PvNode || cutNode) + ((ss - 1)->statScore < -14144) + + ((ss - 1)->moveCount > 9) + (!ss->inCheck && bestValue <= ss->staticEval - 115) + + (!(ss - 1)->inCheck && bestValue <= -(ss - 1)->staticEval - 81); update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq, stat_bonus(depth) * bonus); thisThread->mainHistory[~us][((ss - 1)->currentMove).from_to()] @@ -1513,7 +1513,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta, if (bestValue > alpha) alpha = bestValue; - futilityBase = ss->staticEval + 264; + futilityBase = ss->staticEval + 279; } const PieceToHistory* contHist[] = {(ss - 1)->continuationHistory, @@ -1585,11 +1585,11 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta, + (*contHist[1])[pos.moved_piece(move)][move.to_sq()] + thisThread->pawnHistory[pawn_structure_index(pos)][pos.moved_piece(move)] [move.to_sq()] - <= 4348) + <= 4181) continue; // Do not search moves with bad enough SEE values (~5 Elo) - if (!pos.see_ge(move, -63)) + if (!pos.see_ge(move, -67)) continue; } @@ -1655,7 +1655,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth Search::Worker::reduction(bool i, Depth d, int mn, int delta) { int reductionScale = reductions[d] * reductions[mn]; - return (reductionScale + 1147 - delta * 755 / rootDelta) / 1024 + (!i && reductionScale > 1125); + return (reductionScale + 1222 - delta * 733 / rootDelta) / 1024 + (!i && reductionScale > 1231); } // elapsed() returns the time elapsed since the search started. If the @@ -1758,7 +1758,7 @@ void update_all_stats(const Position& pos, if (!pos.capture_stage(bestMove)) { - int bestMoveBonus = bestValue > beta + 165 ? quietMoveBonus // larger bonus + int bestMoveBonus = bestValue > beta + 176 ? quietMoveBonus // larger bonus : stat_bonus(depth); // smaller bonus update_quiet_stats(pos, ss, workerThread, bestMove, bestMoveBonus); @@ -1796,7 +1796,7 @@ void update_all_stats(const Position& pos, // by moves at ply -1, -2, -3, -4, and -6 with current move. void update_continuation_histories(Stack* ss, Piece pc, Square to, int bonus) { - bonus = bonus * 45 / 64; + bonus = bonus * 47 / 64; for (int i : {1, 2, 3, 4, 6}) {