Time management improvements

[stockfish] / src / timeman.cpp

diff --git a/src/timeman.cpp b/src/timeman.cpp
index 7e77a4add053d6e656558c5d90e1893b517845f6..1253d434672709094cb7496dea0b37f08dc02fb5 100644 (file)
--- a/src/timeman.cpp
+++ b/src/timeman.cpp
@@ -72,7 +72,11 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
                                                   - moveOverhead * (2 + mtg));
 
     // Use extra time with larger increments
-    double optExtra = std::clamp(1.0 + 12.0 * limits.inc[us] / limits.time[us], 1.0, 1.12);
+    double optExtra = std::clamp(1.0 + 12.5 * limits.inc[us] / limits.time[us], 1.0, 1.12);
+
+    // Calculate time constants based on current time left.
+    double optConstant = std::min(0.00335 + 0.0003 * std::log10(limits.time[us] / 1000.0), 0.0048);
+    double maxConstant = std::max(3.6 + 3.0 * std::log10(limits.time[us] / 1000.0), 2.7);
 
     // A user may scale time usage by setting UCI option "Slow Mover"
     // Default is 100 and changing this value will probably lose elo.
@@ -83,10 +87,10 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
     // game time for the current move, so also cap to 20% of available game time.
     if (limits.movestogo == 0)
     {
-        optScale = std::min(0.0120 + std::pow(ply + 3.0, 0.45) * 0.0039,
+        optScale = std::min(0.0120 + std::pow(ply + 3.3, 0.44) * optConstant,
                             0.2 * limits.time[us] / double(timeLeft))
                  * optExtra;
-        maxScale = std::min(7.0, 4.0 + ply / 12.0);
+        maxScale = std::min(6.8, maxConstant + ply / 12.2);
     }
 
     // x moves in y seconds (+ z increment)
@@ -96,10 +100,10 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
         maxScale = std::min(6.3, 1.5 + 0.11 * mtg);
     }
 
-    // Never use more than 80% of the available time for this move
+    // Limit the maximum possible time for this move
     optimumTime = TimePoint(optScale * timeLeft);
     maximumTime =
-      TimePoint(std::min(0.8 * limits.time[us] - moveOverhead, maxScale * optimumTime)) - 10;
+      TimePoint(std::min(0.84 * limits.time[us] - moveOverhead, maxScale * optimumTime)) - 10;
 
     if (Options["Ponder"])
         optimumTime += optimumTime / 4;