/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2014 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 <algorithm>
+#include <cfloat>
#include <cmath>
#include "search.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 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 1 / pow((1 + exp((ply - xshift) / xscale)), skewfactor) + 1e-3; // Ensure non-zero
+ return pow((1 + exp((ply - xshift) / xscale)), -skewfactor) + DBL_MIN; // Ensure non-zero
}
+ 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);
- /// Function Prototypes
-
- enum TimeType { OptimumTime, MaxTime };
+ double thisMoveImportance = (move_importance(currentPly) * slowMover) / 100;
+ double otherMovesImportance = 0;
- template<TimeType>
- int remaining(int myTime, int movesToGo, int fullMoveNumber, int slowMover);
-}
+ 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);
-void TimeManager::pv_instability(double bestMoveChanges) {
+ return int(myTime * std::min(ratio1, ratio2));
+ }
- unstablePVExtraTime = int(bestMoveChanges * optimumSearchTime / 1.4);
-}
+} // namespace
void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color us)
{
- /* We support four different kind of time controls:
+ /* 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:
+ Time management is adjusted by following 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
int hypMTG, hypMyTime, t1, t2;
// 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"];
+ int moveOverhead = Options["Move Overhead"];
+ int minThinkingTime = Options["Minimum Thinking Time"];
+ int slowMover = Options["Slow Mover"];
- // Initialize all to maximum values but unstablePVExtraTime that is reset
- unstablePVExtraTime = 0;
- optimumSearchTime = maximumSearchTime = limits.time[us];
+ // Initialize unstablePvFactor to 1 and search times to maximum values
+ unstablePvFactor = 1;
+ optimumSearchTime = maximumSearchTime = std::max(limits.time[us], minThinkingTime);
// 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.
// Calculate thinking time for hypothetical "moves to go"-value
hypMyTime = limits.time[us]
+ limits.inc[us] * (hypMTG - 1)
- - emergencyBaseTime
- - emergencyMoveTime * std::min(hypMTG, emergencyMoveHorizon);
+ - moveOverhead * (2 + std::min(hypMTG, 40));
hypMyTime = std::max(hypMyTime, 0);
// 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