/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include "search.h"
#include "timeman.h"
-#include "ucioption.h"
+#include "uci.h"
namespace {
- /// Constants
+ enum TimeType { OptimumTime, MaxTime };
const int MoveHorizon = 50; // Plan time management at most this many moves ahead
const double MaxRatio = 7.0; // When in trouble, we can step over reserved time with this ratio
const double StealRatio = 0.33; // However we must not steal time from remaining moves over this ratio
- const double xscale = 9.3;
- const double xshift = 59.8;
- const double skewfactor = 0.172;
-
- /// move_importance() is a skew-logistic function based on naive statistical
- /// analysis of "how many games are still undecided after n half-moves". Game
- /// is considered "undecided" as long as neither side has >275cp advantage.
- /// Data was extracted from CCRL game database with some simple filtering criteria.
+ // move_importance() is a skew-logistic function based on naive statistical
+ // analysis of "how many games are still undecided after n half-moves". Game
+ // is considered "undecided" as long as neither side has >275cp advantage.
+ // Data was extracted from CCRL game database with some simple filtering criteria.
double move_importance(int ply) {
- return pow((1 + exp((ply - xshift) / xscale)), -skewfactor) + DBL_MIN; // Ensure non-zero
+ const double XScale = 9.3;
+ const double XShift = 59.8;
+ const double Skew = 0.172;
+
+ return pow((1 + exp((ply - XShift) / XScale)), -Skew) + DBL_MIN; // Ensure non-zero
}
+ template<TimeType T>
+ int remaining(int myTime, int movesToGo, int ply, int slowMover)
+ {
+ const double TMaxRatio = (T == OptimumTime ? 1 : MaxRatio);
+ const double TStealRatio = (T == OptimumTime ? 0 : StealRatio);
- /// Function Prototypes
+ double moveImportance = (move_importance(ply) * slowMover) / 100;
+ double otherMovesImportance = 0;
- enum TimeType { OptimumTime, MaxTime };
+ for (int i = 1; i < movesToGo; ++i)
+ otherMovesImportance += move_importance(ply + 2 * i);
- template<TimeType>
- int remaining(int myTime, int movesToGo, int fullMoveNumber, int slowMover);
-}
+ double ratio1 = (TMaxRatio * moveImportance) / (TMaxRatio * moveImportance + otherMovesImportance);
+ double ratio2 = (moveImportance + TStealRatio * otherMovesImportance) / (moveImportance + otherMovesImportance);
+ return int(myTime * std::min(ratio1, ratio2)); // Intel C++ asks an explicit cast
+ }
-void TimeManager::pv_instability(double bestMoveChanges) {
+} // namespace
- unstablePVExtraTime = int(bestMoveChanges * optimumSearchTime / 1.4);
-}
+/// init() is called at the beginning of the search and calculates the allowed
+/// thinking time out of the time control and current game ply. We support four
+/// different kinds of time controls, passed in 'limits':
+///
+/// inc == 0 && movestogo == 0 means: x basetime [sudden death!]
+/// inc == 0 && movestogo != 0 means: x moves in y minutes
+/// inc > 0 && movestogo == 0 means: x basetime + z increment
+/// inc > 0 && movestogo != 0 means: x moves in y minutes + z increment
-void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color us)
+void TimeManager::init(const Search::LimitsType& limits, Color us, int ply)
{
- /* We support four different kinds of time controls:
-
- increment == 0 && movesToGo == 0 means: x basetime [sudden death!]
- increment == 0 && movesToGo != 0 means: x moves in y minutes
- increment > 0 && movesToGo == 0 means: x basetime + z increment
- increment > 0 && movesToGo != 0 means: x moves in y minutes + z increment
-
- Time management is adjusted by following UCI parameters:
-
- emergencyMoveHorizon: Be prepared to always play at least this many moves
- emergencyBaseTime : Always attempt to keep at least this much time (in ms) at clock
- emergencyMoveTime : Plus attempt to keep at least this much time for each remaining emergency move
- minThinkingTime : No matter what, use at least this much thinking before doing the move
- */
-
- int hypMTG, hypMyTime, t1, t2;
+ int minThinkingTime = Options["Minimum Thinking Time"];
+ int moveOverhead = Options["Move Overhead"];
+ int slowMover = Options["Slow Mover"];
- // Read uci parameters
- int emergencyMoveHorizon = Options["Emergency Move Horizon"];
- int emergencyBaseTime = Options["Emergency Base Time"];
- int emergencyMoveTime = Options["Emergency Move Time"];
- int minThinkingTime = Options["Minimum Thinking Time"];
- int slowMover = Options["Slow Mover"];
+ // Initialize unstablePvFactor to 1 and search times to maximum values
+ unstablePvFactor = 1;
+ optimumSearchTime = maximumSearchTime = std::max(limits.time[us], minThinkingTime);
- // Initialize all to maximum values but unstablePVExtraTime that is reset
- unstablePVExtraTime = 0;
- optimumSearchTime = maximumSearchTime = limits.time[us];
+ const int MaxMTG = limits.movestogo ? std::min(limits.movestogo, MoveHorizon) : MoveHorizon;
- // We calculate optimum time usage for different hypothetical "moves to go"-values and choose the
- // minimum of calculated search time values. Usually the greatest hypMTG gives the minimum values.
- for (hypMTG = 1; hypMTG <= (limits.movestogo ? std::min(limits.movestogo, MoveHorizon) : MoveHorizon); ++hypMTG)
+ // We calculate optimum time usage for different hypothetical "moves to go"-values
+ // and choose the minimum of calculated search time values. Usually the greatest
+ // hypMTG gives the minimum values.
+ for (int hypMTG = 1; hypMTG <= MaxMTG; ++hypMTG)
{
// Calculate thinking time for hypothetical "moves to go"-value
- hypMyTime = limits.time[us]
- + limits.inc[us] * (hypMTG - 1)
- - emergencyBaseTime
- - emergencyMoveTime * std::min(hypMTG, emergencyMoveHorizon);
+ int hypMyTime = limits.time[us]
+ + limits.inc[us] * (hypMTG - 1)
+ - moveOverhead * (2 + std::min(hypMTG, 40));
hypMyTime = std::max(hypMyTime, 0);
- t1 = minThinkingTime + remaining<OptimumTime>(hypMyTime, hypMTG, currentPly, slowMover);
- t2 = minThinkingTime + remaining<MaxTime>(hypMyTime, hypMTG, currentPly, slowMover);
+ int t1 = minThinkingTime + remaining<OptimumTime>(hypMyTime, hypMTG, ply, slowMover);
+ int t2 = minThinkingTime + remaining<MaxTime >(hypMyTime, hypMTG, ply, slowMover);
- optimumSearchTime = std::min(optimumSearchTime, t1);
- maximumSearchTime = std::min(maximumSearchTime, t2);
+ optimumSearchTime = std::min(t1, optimumSearchTime);
+ maximumSearchTime = std::min(t2, maximumSearchTime);
}
if (Options["Ponder"])
optimumSearchTime += optimumSearchTime / 4;
- // Make sure that maxSearchTime is not over absoluteMaxSearchTime
optimumSearchTime = std::min(optimumSearchTime, maximumSearchTime);
}
-
-
-namespace {
-
- template<TimeType T>
- int remaining(int myTime, int movesToGo, int currentPly, int slowMover)
- {
- const double TMaxRatio = (T == OptimumTime ? 1 : MaxRatio);
- const double TStealRatio = (T == OptimumTime ? 0 : StealRatio);
-
- double thisMoveImportance = (move_importance(currentPly) * slowMover) / 100;
- double otherMovesImportance = 0;
-
- for (int i = 1; i < movesToGo; ++i)
- otherMovesImportance += move_importance(currentPly + 2 * i);
-
- double ratio1 = (TMaxRatio * thisMoveImportance) / (TMaxRatio * thisMoveImportance + otherMovesImportance);
- double ratio2 = (thisMoveImportance + TStealRatio * otherMovesImportance) / (thisMoveImportance + otherMovesImportance);
-
- return int(floor(myTime * std::min(ratio1, ratio2)));
- }
-}
projects / stockfish / blobdiff