X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftimeman.cpp;h=ea1e92d2aca5ca57ef0c6c2a6942ea2717d65753;hp=9fedd1ce4d2b1efc9a6a70e117f5d98270c3ff5d;hb=e10255339fc7cb54bb0466945f759646f442f4f0;hpb=c150f07291aa3205d630351e21f5b6826b6c9f12 diff --git a/src/timeman.cpp b/src/timeman.cpp index 9fedd1ce..ea1e92d2 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 @@ -18,52 +19,57 @@ */ #include -#include -#include #include "search.h" #include "timeman.h" #include "uci.h" +TimeManagement Time; // Our global time management object + namespace { 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 + int remaining(int myTime, int myInc, int moveOverhead, int movesToGo, + int moveNum, bool ponder, TimeType type) { + if (myTime <= 0) + return 0; - // 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 ratio; // Which ratio of myTime we are going to use - double move_importance(int ply) { + // Usage of increment follows quadratic distribution with the maximum at move 25 + double inc = myInc * std::max(55.0, 120 - 0.12 * (moveNum - 25) * (moveNum - 25)); - const double XScale = 9.3; - const double XShift = 59.8; - const double Skew = 0.172; + // 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); - return pow((1 + exp((ply - XShift) / XScale)), -Skew) + DBL_MIN; // Ensure non-zero - } + if (moveNum <= 40) + ratio *= 1.1 - 0.001 * (moveNum - 20) * (moveNum - 20); + else + ratio *= 1.5; - template - int remaining(int myTime, int movesToGo, int ply, int slowMover) - { - const double TMaxRatio = (T == OptimumTime ? 1 : MaxRatio); - const double TStealRatio = (T == OptimumTime ? 0 : StealRatio); + ratio *= 1 + inc / (myTime * 8.5); + } + // Otherwise we increase usage of remaining time as the game goes on + else + { + double k = 1 + 20 * moveNum / (500.0 + moveNum); + ratio = (type == OptimumTime ? 0.017 : 0.07) * (k + inc / myTime); + } - double moveImportance = (move_importance(ply) * slowMover) / 100; - double otherMovesImportance = 0; + int time = int(std::min(1.0, ratio) * std::max(0, myTime - moveOverhead)); - for (int i = 1; i < movesToGo; ++i) - otherMovesImportance += move_importance(ply + 2 * i); + if (type == OptimumTime && ponder) + time *= 1.25; - double ratio1 = (TMaxRatio * moveImportance) / (TMaxRatio * moveImportance + otherMovesImportance); - double ratio2 = (moveImportance + TStealRatio * otherMovesImportance) / (moveImportance + otherMovesImportance); + if (type == MaxTime) + time -= 10; // Keep always at least 10 millisecs on the clock - return int(myTime * std::min(ratio1, ratio2)); // Intel C++ asks an explicit cast + return std::max(0, time); } } // namespace @@ -78,39 +84,32 @@ namespace { /// 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, Color us, int ply) +void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) { - int minThinkingTime = Options["Minimum Thinking Time"]; - int moveOverhead = Options["Move Overhead"]; - 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); - - 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 (int hypMTG = 1; hypMTG <= MaxMTG; ++hypMTG) + 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) { - // Calculate thinking time for hypothetical "moves to go"-value - int hypMyTime = limits.time[us] - + limits.inc[us] * (hypMTG - 1) - - moveOverhead * (2 + std::min(hypMTG, 40)); - - hypMyTime = std::max(hypMyTime, 0); - - int t1 = minThinkingTime + remaining(hypMyTime, hypMTG, ply, slowMover); - int t2 = minThinkingTime + remaining(hypMyTime, hypMTG, ply, slowMover); + if (!availableNodes) // Only once at game start + availableNodes = npmsec * limits.time[us]; // Time is in msec - optimumSearchTime = std::min(t1, optimumSearchTime); - maximumSearchTime = std::min(t2, maximumSearchTime); + // Convert from millisecs to nodes + limits.time[us] = (int)availableNodes; + limits.inc[us] *= npmsec; + limits.npmsec = npmsec; } - if (Options["Ponder"]) - optimumSearchTime += optimumSearchTime / 4; + int moveNum = (ply + 1) / 2; - optimumSearchTime = std::min(optimumSearchTime, maximumSearchTime); + startTime = limits.startTime; + optimumTime = remaining(limits.time[us], limits.inc[us], moveOverhead, + limits.movestogo, moveNum, ponder, OptimumTime); + maximumTime = remaining(limits.time[us], limits.inc[us], moveOverhead, + limits.movestogo, moveNum, ponder, MaxTime); }