X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftimeman.cpp;h=b5d1a66c30b05faf1d26da029ebd42ab7bbdfe8a;hp=702f0f31eafb8f7d751552078bf12b18a889e6f9;hb=daf0fe1f57337d33f9e0af5a8aa8ef0868b20417;hpb=cabd512916f1121a254c367a9fbba7978a57b5ae diff --git a/src/timeman.cpp b/src/timeman.cpp index 702f0f31..b5d1a66c 100644 --- a/src/timeman.cpp +++ b/src/timeman.cpp @@ -1,7 +1,8 @@ /* 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 + Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -18,126 +19,99 @@ */ #include -#include -#include #include "search.h" #include "timeman.h" -#include "ucioption.h" +#include "uci.h" -namespace { - - /// Constants - - 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. - - double move_importance(int ply) { +TimeManagement Time; // Our global time management object - return pow((1 + exp((ply - xshift) / xscale)), -skewfactor) + DBL_MIN; // Ensure non-zero - } - - - /// Function Prototypes +namespace { enum TimeType { OptimumTime, MaxTime }; - template - int remaining(int myTime, int movesToGo, int fullMoveNumber, int slowMover); -} + int remaining(int myTime, int myInc, int moveOverhead, int movesToGo, + int ply, bool ponder, TimeType type) { + if (myTime <= 0) + return 0; -void TimeManager::pv_instability(double bestMoveChanges) { + int moveNumber = (ply + 1) / 2; + double ratio; // Which ratio of myTime we are going to use. It's <= 1 if not ponder + double sd = 8.5; - unstablePVExtraTime = int(bestMoveChanges * optimumSearchTime / 1.4); -} + // Usage of increment follows quadratic distribution with the maximum at move 25 + double inc = myInc * std::max(55.0, 120.0 - 0.12 * (moveNumber - 25) * (moveNumber - 25)); + // In moves-to-go we distribute time according to a quadratic function with + // the maximum around move 20 for 40 moves in y time case. + if (movesToGo) + { + ratio = (type == OptimumTime ? 1.0 : 6.0) / std::min(50, movesToGo); -void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color us) -{ - /* We support four different kinds of time controls: + if (moveNumber <= 40) + ratio *= 1.1 - 0.001 * (moveNumber - 20) * (moveNumber - 20); + else + ratio *= 1.5; + } + // Otherwise we increase usage of remaining time as the game goes on + else + { + sd = 1 + 20 * moveNumber / (500.0 + moveNumber); + ratio = (type == OptimumTime ? 0.017 : 0.07) * sd; + } - 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 + ratio = std::min(1.0, ratio * (1 + inc / (myTime * sd))); - Time management is adjusted by following UCI parameters: + assert(ratio <= 1); - 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 - */ + if (ponder && type == OptimumTime) + ratio *= 1.25; - int hypMTG, hypMyTime, t1, t2; + int time = int(ratio * (myTime - moveOverhead)); - // 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"]; + if (type == OptimumTime) + time -= 10; // Keep always at least 10 millisecs on the clock - // Initialize all to maximum values but unstablePVExtraTime that is reset - unstablePVExtraTime = 0; - 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. - for (hypMTG = 1; hypMTG <= (limits.movestogo ? std::min(limits.movestogo, MoveHorizon) : MoveHorizon); ++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); - - hypMyTime = std::max(hypMyTime, 0); - - t1 = minThinkingTime + remaining(hypMyTime, hypMTG, currentPly, slowMover); - t2 = minThinkingTime + remaining(hypMyTime, hypMTG, currentPly, slowMover); - - optimumSearchTime = std::min(optimumSearchTime, t1); - maximumSearchTime = std::min(maximumSearchTime, t2); + return std::max(0, time); } - if (Options["Ponder"]) - optimumSearchTime += optimumSearchTime / 4; +} // namespace - // Make sure that maxSearchTime is not over absoluteMaxSearchTime - optimumSearchTime = std::min(optimumSearchTime, maximumSearchTime); -} +/// 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 -namespace { - - template - int remaining(int myTime, int movesToGo, int currentPly, int slowMover) +void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) +{ + int moveOverhead = Options["Move Overhead"]; + int npmsec = Options["nodestime"]; + bool ponder = Options["Ponder"]; + + // If we have to play in 'nodes as time' mode, then convert from time + // to nodes, and use resulting values in time management formulas. + // WARNING: Given npms (nodes per millisecond) must be much lower then + // the real engine speed to avoid time losses. + if (npmsec) { - const double TMaxRatio = (T == OptimumTime ? 1 : MaxRatio); - const double TStealRatio = (T == OptimumTime ? 0 : StealRatio); - - double thisMoveImportance = (move_importance(currentPly) * slowMover) / 100; - double otherMovesImportance = 0; + if (!availableNodes) // Only once at game start + availableNodes = npmsec * limits.time[us]; // Time is in msec - 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))); + // Convert from millisecs to nodes + limits.time[us] = (int)availableNodes; + limits.inc[us] *= npmsec; + limits.npmsec = npmsec; } + + startTime = limits.startTime; + optimumTime = remaining(limits.time[us], limits.inc[us], moveOverhead, + limits.movestogo, ply, ponder, OptimumTime); + maximumTime = remaining(limits.time[us], limits.inc[us], moveOverhead, + limits.movestogo, ply, ponder, MaxTime); }