Assorted search and eval parameter tune

Search and eval parameter tune.

STC https://tests.stockfishchess.org/tests/view/5fba850a67cbf42301d6b07d
LLR: 2.94 (-2.94,2.94) {-0.25,1.25}
Total: 24312 W: 2388 L: 2228 D: 19696
Ptnml(0-2): 85, 1800, 8241, 1930, 100

LTC https://tests.stockfishchess.org/tests/view/5fbad5ea67cbf42301d6b0fa
LLR: 2.95 (-2.94,2.94) {0.25,1.25}
Total: 88376 W: 3619 L: 3351 D: 81406
Ptnml(0-2): 56, 2977, 37849, 3255, 51

closes https://github.com/official-stockfish/Stockfish/pull/3232

bench: 3600361

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 1a8cf662c6f46caa494a27bfaf84f8d24362b86f..3d8871191f96f0180fd2d98a95dcf6dd0a4e6dd8 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -187,11 +187,11 @@ using namespace Trace;
 namespace {
 
   // Threshold for lazy and space evaluation
-  constexpr Value LazyThreshold1 =  Value(1400);
-  constexpr Value LazyThreshold2 =  Value(1300);
-  constexpr Value SpaceThreshold = Value(12222);
-  constexpr Value NNUEThreshold1 =   Value(550);
-  constexpr Value NNUEThreshold2 =   Value(150);
+  constexpr Value LazyThreshold1 =  Value(1565);
+  constexpr Value LazyThreshold2 =  Value(1102);
+  constexpr Value SpaceThreshold = Value(11551);
+  constexpr Value NNUEThreshold1 =   Value(682);
+  constexpr Value NNUEThreshold2 =   Value(176);
 
   // KingAttackWeights[PieceType] contains king attack weights by piece type
   constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };

diff --git a/src/search.cpp b/src/search.cpp
index 78a1f7b6eb9e038a5c24f415dd127a2ddb67c13b..7c797bef4087a2e62d58a1fe88359763fbe139e9 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -65,7 +65,7 @@ namespace {
   // Razor and futility margins
   constexpr int RazorMargin = 510;
   Value futility_margin(Depth d, bool improving) {
-    return Value(223 * (d - improving));
+    return Value(234 * (d - improving));
   }
 
   // Reductions lookup table, initialized at startup
@@ -73,7 +73,7 @@ namespace {
 
   Depth reduction(bool i, Depth d, int mn) {
     int r = Reductions[d] * Reductions[mn];
-    return (r + 509) / 1024 + (!i && r > 894);
+    return (r + 503) / 1024 + (!i && r > 915);
   }
 
   constexpr int futility_move_count(bool improving, Depth depth) {
@@ -194,7 +194,7 @@ namespace {
 void Search::init() {
 
   for (int i = 1; i < MAX_MOVES; ++i)
-      Reductions[i] = int((22.0 + 2 * std::log(Threads.size())) * std::log(i + 0.25 * std::log(i)));
+      Reductions[i] = int((21.3 + 2 * std::log(Threads.size())) * std::log(i + 0.25 * std::log(i)));
 }
 
 
@@ -410,7 +410,7 @@ void Thread::search() {
               beta  = std::min(prev + delta, VALUE_INFINITE);
 
               // Adjust contempt based on root move's previousScore (dynamic contempt)
-              int dct = ct + (105 - ct / 2) * prev / (abs(prev) + 149);
+              int dct = ct + (113 - ct / 2) * prev / (abs(prev) + 147);
 
               contempt = (us == WHITE ?  make_score(dct, dct / 2)
                                       : -make_score(dct, dct / 2));
@@ -830,7 +830,7 @@ namespace {
         && (ss-1)->statScore < 22977
         &&  eval >= beta
         &&  eval >= ss->staticEval
-        &&  ss->staticEval >= beta - 30 * depth - 28 * improving + 84 * ss->ttPv + 182
+        &&  ss->staticEval >= beta - 30 * depth - 28 * improving + 84 * ss->ttPv + 168
         && !excludedMove
         &&  pos.non_pawn_material(us)
         && (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor))
@@ -838,7 +838,7 @@ namespace {
         assert(eval - beta >= 0);
 
         // Null move dynamic reduction based on depth and value
-        Depth R = (982 + 85 * depth) / 256 + std::min(int(eval - beta) / 192, 3);
+        Depth R = (1015 + 85 * depth) / 256 + std::min(int(eval - beta) / 191, 3);
 
         ss->currentMove = MOVE_NULL;
         ss->continuationHistory = &thisThread->continuationHistory[0][0][NO_PIECE][0];
@@ -855,7 +855,7 @@ namespace {
             if (nullValue >= VALUE_TB_WIN_IN_MAX_PLY)
                 nullValue = beta;
 
-            if (thisThread->nmpMinPly || (abs(beta) < VALUE_KNOWN_WIN && depth < 13))
+            if (thisThread->nmpMinPly || (abs(beta) < VALUE_KNOWN_WIN && depth < 14))
                 return nullValue;
 
             assert(!thisThread->nmpMinPly); // Recursive verification is not allowed
@@ -874,7 +874,7 @@ namespace {
         }
     }
 
-    probCutBeta = beta + 176 - 49 * improving;
+    probCutBeta = beta + 183 - 49 * improving;
 
     // Step 10. ProbCut (~10 Elo)
     // If we have a good enough capture and a reduced search returns a value
@@ -1039,7 +1039,7 @@ moves_loop: // When in check, search starts from here
               // Futility pruning: parent node (~5 Elo)
               if (   lmrDepth < 7
                   && !ss->inCheck
-                  && ss->staticEval + 283 + 170 * lmrDepth <= alpha
+                  && ss->staticEval + 266 + 170 * lmrDepth <= alpha
                   &&  (*contHist[0])[movedPiece][to_sq(move)]
                     + (*contHist[1])[movedPiece][to_sq(move)]
                     + (*contHist[3])[movedPiece][to_sq(move)]
@@ -1047,7 +1047,7 @@ moves_loop: // When in check, search starts from here
                   continue;
 
               // Prune moves with negative SEE (~20 Elo)
-              if (!pos.see_ge(move, Value(-(29 - std::min(lmrDepth, 18)) * lmrDepth * lmrDepth)))
+              if (!pos.see_ge(move, Value(-(30 - std::min(lmrDepth, 18)) * lmrDepth * lmrDepth)))
                   continue;
           }
           else
@@ -1059,7 +1059,7 @@ moves_loop: // When in check, search starts from here
                   continue;
 
               // SEE based pruning
-              if (!pos.see_ge(move, Value(-221) * depth)) // (~25 Elo)
+              if (!pos.see_ge(move, Value(-213) * depth)) // (~25 Elo)
                   continue;
           }
       }
@@ -1153,12 +1153,12 @@ moves_loop: // When in check, search starts from here
               || moveCountPruning
               || ss->staticEval + PieceValue[EG][pos.captured_piece()] <= alpha
               || cutNode
-              || thisThread->ttHitAverage < 427 * TtHitAverageResolution * TtHitAverageWindow / 1024))
+              || thisThread->ttHitAverage < 432 * TtHitAverageResolution * TtHitAverageWindow / 1024))
       {
           Depth r = reduction(improving, depth, moveCount);
 
           // Decrease reduction if the ttHit running average is large
-          if (thisThread->ttHitAverage > 509 * TtHitAverageResolution * TtHitAverageWindow / 1024)
+          if (thisThread->ttHitAverage > 537 * TtHitAverageResolution * TtHitAverageWindow / 1024)
               r--;
 
           // Increase reduction if other threads are searching this position
@@ -1211,10 +1211,10 @@ moves_loop: // When in check, search starts from here
                              - 5287;
 
               // Decrease/increase reduction by comparing opponent's stat score (~10 Elo)
-              if (ss->statScore >= -106 && (ss-1)->statScore < -104)
+              if (ss->statScore >= -105 && (ss-1)->statScore < -103)
                   r--;
 
-              else if ((ss-1)->statScore >= -119 && ss->statScore < -140)
+              else if ((ss-1)->statScore >= -122 && ss->statScore < -129)
                   r++;
 
               // Decrease/increase reduction for moves with a good/bad history (~30 Elo)
@@ -1228,7 +1228,7 @@ moves_loop: // When in check, search starts from here
 
               // Unless giving check, this capture is likely bad
               if (   !givesCheck
-                  && ss->staticEval + PieceValue[EG][pos.captured_piece()] + 213 * depth <= alpha)
+                  && ss->staticEval + PieceValue[EG][pos.captured_piece()] + 210 * depth <= alpha)
                   r++;
           }
 
@@ -1502,7 +1502,7 @@ moves_loop: // When in check, search starts from here
         if (PvNode && bestValue > alpha)
             alpha = bestValue;
 
-        futilityBase = bestValue + 145;
+        futilityBase = bestValue + 155;
     }
 
     const PieceToHistory* contHist[] = { (ss-1)->continuationHistory, (ss-2)->continuationHistory,