From 6294db7514798ac12536b4d6e77bc591f7e846da Mon Sep 17 00:00:00 2001 From: Vizvezdenec Date: Fri, 19 Feb 2021 10:32:12 +0300 Subject: [PATCH] Tune search parameters (with Unai Corzo) The values used in this patch are taken from a SPSA parameter tuning session originated by Unai Corzo (@unaiic), but the final difference of his tune was multiplied x2 by hand. Most of the credits should go to him :-) STC: https://tests.stockfishchess.org/tests/view/602f03d07f517a561bc49d40 LLR: 2.94 (-2.94,2.94) {-0.25,1.25} Total: 67664 W: 6252 L: 6035 D: 55377 Ptnml(0-2): 256, 4799, 23527, 4972, 278 LTC: https://tests.stockfishchess.org/tests/view/602f41697f517a561bc49d5a LLR: 2.96 (-2.94,2.94) {0.25,1.25} Total: 26256 W: 1034 L: 906 D: 24316 Ptnml(0-2): 10, 804, 11377, 922, 15 Closes https://github.com/official-stockfish/Stockfish/pull/3363 Bench: 3957653 --- src/search.cpp | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index b5d21b9d..8f01f785 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -839,7 +839,7 @@ namespace { // Step 8. Null move search with verification search (~40 Elo) if ( !PvNode && (ss-1)->currentMove != MOVE_NULL - && (ss-1)->statScore < 22661 + && (ss-1)->statScore < 24185 && eval >= beta && eval >= ss->staticEval && ss->staticEval >= beta - 24 * depth - 34 * improving + 162 * ss->ttPv + 159 @@ -1075,7 +1075,7 @@ 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)] - + (*contHist[5])[movedPiece][to_sq(move)] / 3 < 26237) + + (*contHist[5])[movedPiece][to_sq(move)] / 3 < 28255) continue; // Prune moves with negative SEE (~20 Elo) @@ -1167,7 +1167,7 @@ moves_loop: // When in check, search starts from here || moveCountPruning || ss->staticEval + PieceValue[EG][pos.captured_piece()] <= alpha || cutNode - || (!PvNode && !formerPv && captureHistory[movedPiece][to_sq(move)][type_of(pos.captured_piece())] < 4506) + || (!PvNode && !formerPv && captureHistory[movedPiece][to_sq(move)][type_of(pos.captured_piece())] < 3678) || thisThread->ttHitAverage < 432 * TtHitAverageResolution * TtHitAverageWindow / 1024)) { Depth r = reduction(improving, depth, moveCount); @@ -1232,7 +1232,7 @@ 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)] - - 5337; + - 4741; // Decrease/increase reduction by comparing opponent's stat score (~10 Elo) if (ss->statScore >= -89 && (ss-1)->statScore < -116) @@ -1246,9 +1246,9 @@ 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)] - 4341) / 16384; + + (*contHist[0])[movedPiece][to_sq(move)] - 3833) / 16384; else - r -= ss->statScore / 14382; + r -= ss->statScore / 14790; } Depth d = std::clamp(newDepth - r, 1, newDepth); -- 2.39.2