/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2015-2018 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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-#include <cmath>
#include <algorithm>
+#include <cfloat>
+#include <cmath>
-#include "misc.h"
#include "search.h"
#include "timeman.h"
-#include "ucioption.h"
+#include "uci.h"
-namespace {
+TimeManagement Time; // Our global time management object
- /// Constants
-
- const int MoveHorizon = 50; // Plan time management at most this many moves ahead
- const float MaxRatio = 3.0f; // When in trouble, we can step over reserved time with this ratio
- const float StealRatio = 0.33f; // However we must not steal time from remaining moves over this ratio
-
-
- // MoveImportance[] is 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.
- const int MoveImportance[512] = {
- 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780, 7780,
- 7780, 7780, 7780, 7780, 7778, 7778, 7776, 7776, 7776, 7773, 7770, 7768, 7766, 7763, 7757, 7751,
- 7743, 7735, 7724, 7713, 7696, 7689, 7670, 7656, 7627, 7605, 7571, 7549, 7522, 7493, 7462, 7425,
- 7385, 7350, 7308, 7272, 7230, 7180, 7139, 7094, 7055, 7010, 6959, 6902, 6841, 6778, 6705, 6651,
- 6569, 6508, 6435, 6378, 6323, 6253, 6152, 6085, 5995, 5931, 5859, 5794, 5717, 5646, 5544, 5462,
- 5364, 5282, 5172, 5078, 4988, 4901, 4831, 4764, 4688, 4609, 4536, 4443, 4365, 4293, 4225, 4155,
- 4085, 4005, 3927, 3844, 3765, 3693, 3634, 3560, 3479, 3404, 3331, 3268, 3207, 3146, 3077, 3011,
- 2947, 2894, 2828, 2776, 2727, 2676, 2626, 2589, 2538, 2490, 2442, 2394, 2345, 2302, 2243, 2192,
- 2156, 2115, 2078, 2043, 2004, 1967, 1922, 1893, 1845, 1809, 1772, 1736, 1702, 1674, 1640, 1605,
- 1566, 1536, 1509, 1479, 1452, 1423, 1388, 1362, 1332, 1304, 1289, 1266, 1250, 1228, 1206, 1180,
- 1160, 1134, 1118, 1100, 1080, 1068, 1051, 1034, 1012, 1001, 980, 960, 945, 934, 916, 900, 888,
- 878, 865, 852, 828, 807, 787, 770, 753, 744, 731, 722, 706, 700, 683, 676, 671, 664, 652, 641,
- 634, 627, 613, 604, 591, 582, 568, 560, 552, 540, 534, 529, 519, 509, 495, 484, 474, 467, 460,
- 450, 438, 427, 419, 410, 406, 399, 394, 387, 382, 377, 372, 366, 359, 353, 348, 343, 337, 333,
- 328, 321, 315, 309, 303, 298, 293, 287, 284, 281, 277, 273, 265, 261, 255, 251, 247, 241, 240,
- 235, 229, 218, 217, 213, 212, 208, 206, 197, 193, 191, 189, 185, 184, 180, 177, 172, 170, 170,
- 170, 166, 163, 159, 158, 156, 155, 151, 146, 141, 138, 136, 132, 130, 128, 125, 123, 122, 118,
- 118, 118, 117, 115, 114, 108, 107, 105, 105, 105, 102, 97, 97, 95, 94, 93, 91, 88, 86, 83, 80,
- 80, 79, 79, 79, 78, 76, 75, 72, 72, 71, 70, 68, 65, 63, 61, 61, 59, 59, 59, 58, 56, 55, 54, 54,
- 52, 49, 48, 48, 48, 48, 45, 45, 45, 44, 43, 41, 41, 41, 41, 40, 40, 38, 37, 36, 34, 34, 34, 33,
- 31, 29, 29, 29, 28, 28, 28, 28, 28, 28, 28, 27, 27, 27, 27, 27, 24, 24, 23, 23, 22, 21, 20, 20,
- 19, 19, 19, 19, 19, 18, 18, 18, 18, 17, 17, 17, 17, 17, 16, 16, 15, 15, 14, 14, 14, 12, 12, 11,
- 9, 9, 9, 9, 9, 9, 9, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
- 8, 8, 8, 8, 7, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
- 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 3, 2, 2, 2, 2,
- 2, 1, 1, 1, 1, 1, 1, 1 };
-
- int move_importance(int ply) { return MoveImportance[std::min(ply, 511)]; }
-
-
- /// Function Prototypes
+namespace {
enum TimeType { OptimumTime, MaxTime };
- template<TimeType>
- int remaining(int myTime, int movesToGo, int fullMoveNumber);
-}
+ constexpr int MoveHorizon = 50; // Plan time management at most this many moves ahead
+ constexpr double MaxRatio = 7.3; // When in trouble, we can step over reserved time with this ratio
+ constexpr double StealRatio = 0.34; // However we must not steal time from remaining moves over this ratio
-void TimeManager::pv_instability(int curChanges, int prevChanges) {
+ // 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 the CCRL game database with some simple filtering criteria.
- unstablePVExtraTime = curChanges * (optimumSearchTime / 2)
- + prevChanges * (optimumSearchTime / 3);
-}
+ double move_importance(int ply) {
+ constexpr double XScale = 6.85;
+ constexpr double XShift = 64.5;
+ constexpr double Skew = 0.171;
-void TimeManager::init(const SearchLimits& limits, int currentPly)
-{
- /* We support four different kind of time controls:
+ return pow((1 + exp((ply - XShift) / XScale)), -Skew) + DBL_MIN; // Ensure non-zero
+ }
- 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
+ template<TimeType T>
+ TimePoint remaining(TimePoint myTime, int movesToGo, int ply, TimePoint slowMover) {
- Time management is adjusted by following UCI parameters:
+ constexpr double TMaxRatio = (T == OptimumTime ? 1.0 : MaxRatio);
+ constexpr double TStealRatio = (T == OptimumTime ? 0.0 : StealRatio);
- 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
- */
+ double moveImportance = (move_importance(ply) * slowMover) / 100.0;
+ double otherMovesImportance = 0.0;
- int hypMTG, hypMyTime, t1, t2;
+ for (int i = 1; i < movesToGo; ++i)
+ otherMovesImportance += move_importance(ply + 2 * i);
- // Read uci parameters
- int emergencyMoveHorizon = Options["Emergency Move Horizon"].value<int>();
- int emergencyBaseTime = Options["Emergency Base Time"].value<int>();
- int emergencyMoveTime = Options["Emergency Move Time"].value<int>();
- int minThinkingTime = Options["Minimum Thinking Time"].value<int>();
+ double ratio1 = (TMaxRatio * moveImportance) / (TMaxRatio * moveImportance + otherMovesImportance);
+ double ratio2 = (moveImportance + TStealRatio * otherMovesImportance) / (moveImportance + otherMovesImportance);
- // Initialize to maximum values but unstablePVExtraTime that is reset
- unstablePVExtraTime = 0;
- optimumSearchTime = maximumSearchTime = limits.time;
+ return TimePoint(myTime * std::min(ratio1, ratio2)); // Intel C++ asks for an explicit cast
+ }
- // We calculate optimum time usage for different hypothetic "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 hypothetic "moves to go"-value
- hypMyTime = limits.time
- + limits.increment * (hypMTG - 1)
- - emergencyBaseTime
- - emergencyMoveTime * std::min(hypMTG, emergencyMoveHorizon);
+} // namespace
- hypMyTime = std::max(hypMyTime, 0);
- t1 = minThinkingTime + remaining<OptimumTime>(hypMyTime, hypMTG, currentPly);
- t2 = minThinkingTime + remaining<MaxTime>(hypMyTime, hypMTG, currentPly);
+/// 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
- optimumSearchTime = std::min(optimumSearchTime, t1);
- maximumSearchTime = std::min(maximumSearchTime, t2);
- }
+void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
- if (Options["Ponder"].value<bool>())
- optimumSearchTime += optimumSearchTime / 4;
+ TimePoint minThinkingTime = Options["Minimum Thinking Time"];
+ TimePoint moveOverhead = Options["Move Overhead"];
+ TimePoint slowMover = Options["Slow Mover"];
+ TimePoint npmsec = Options["nodestime"];
+ TimePoint hypMyTime;
- // Make sure that maxSearchTime is not over absoluteMaxSearchTime
- optimumSearchTime = std::min(optimumSearchTime, maximumSearchTime);
-}
+ // 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: to avoid time losses, the given npmsec (nodes per millisecond)
+ // must be much lower than the real engine speed.
+ if (npmsec)
+ {
+ if (!availableNodes) // Only once at game start
+ availableNodes = npmsec * limits.time[us]; // Time is in msec
+ // Convert from milliseconds to nodes
+ limits.time[us] = TimePoint(availableNodes);
+ limits.inc[us] *= npmsec;
+ limits.npmsec = npmsec;
+ }
-namespace {
+ startTime = limits.startTime;
+ optimumTime = maximumTime = std::max(limits.time[us], minThinkingTime);
- template<TimeType T>
- int remaining(int myTime, int movesToGo, int currentPly)
- {
- const float TMaxRatio = (T == OptimumTime ? 1 : MaxRatio);
- const float TStealRatio = (T == OptimumTime ? 0 : StealRatio);
+ const int maxMTG = limits.movestogo ? std::min(limits.movestogo, MoveHorizon) : MoveHorizon;
- int thisMoveImportance = move_importance(currentPly);
- int otherMovesImportance = 0;
+ // 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)
+ - moveOverhead * (2 + std::min(hypMTG, 40));
- for (int i = 1; i < movesToGo; i++)
- otherMovesImportance += move_importance(currentPly + 2 * i);
+ hypMyTime = std::max(hypMyTime, TimePoint(0));
- float ratio1 = (TMaxRatio * thisMoveImportance) / float(TMaxRatio * thisMoveImportance + otherMovesImportance);
- float ratio2 = (thisMoveImportance + TStealRatio * otherMovesImportance) / float(thisMoveImportance + otherMovesImportance);
+ TimePoint t1 = minThinkingTime + remaining<OptimumTime>(hypMyTime, hypMTG, ply, slowMover);
+ TimePoint t2 = minThinkingTime + remaining<MaxTime >(hypMyTime, hypMTG, ply, slowMover);
- return int(floor(myTime * std::min(ratio1, ratio2)));
+ optimumTime = std::min(t1, optimumTime);
+ maximumTime = std::min(t2, maximumTime);
}
+
+ if (Options["Ponder"])
+ optimumTime += optimumTime / 4;
}
projects / stockfish / blobdiff