/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
- Copyright (C) 2015-2020 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+ Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
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 "timeman.h"
#include "uci.h"
+namespace Stockfish {
+
TimeManagement Time; // Our global time management object
-/// init() is called at the beginning of the search and calculates the bounds
-/// of time allowed for the current game ply. We currently support:
-// 1) x basetime (+z increment)
-// 2) x moves in y seconds (+z increment)
+
+/// TimeManagement::init() is called at the beginning of the search and calculates
+/// the bounds of time allowed for the current game ply. We currently support:
+// 1) x basetime (+ z increment)
+// 2) x moves in y seconds (+ z increment)
void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
- TimePoint minThinkingTime = TimePoint(Options["Minimum Thinking Time"]);
TimePoint moveOverhead = TimePoint(Options["Move Overhead"]);
TimePoint slowMover = TimePoint(Options["Slow Mover"]);
TimePoint npmsec = TimePoint(Options["nodestime"]);
- // opt_scale is a percentage of available time to use for the current move.
- // max_scale is a multiplier applied to optimumTime.
- double opt_scale, max_scale;
+ // optScale is a percentage of available time to use for the current move.
+ // maxScale is a multiplier applied to optimumTime.
+ double optScale, maxScale;
// If we have to play in 'nodes as time' mode, then convert from time
// to nodes, and use resulting values in time management formulas.
startTime = limits.startTime;
- //Maximum move horizon of 50 moves
+ // Maximum move horizon of 50 moves
int mtg = limits.movestogo ? std::min(limits.movestogo, 50) : 50;
// Make sure timeLeft is > 0 since we may use it as a divisor
TimePoint timeLeft = std::max(TimePoint(1),
limits.time[us] + limits.inc[us] * (mtg - 1) - moveOverhead * (2 + mtg));
+ // Use extra time with larger increments
+ double optExtra = std::clamp(1.0 + 12.0 * limits.inc[us] / limits.time[us], 1.0, 1.12);
+
// A user may scale time usage by setting UCI option "Slow Mover"
// Default is 100 and changing this value will probably lose elo.
timeLeft = slowMover * timeLeft / 100;
// game time for the current move, so also cap to 20% of available game time.
if (limits.movestogo == 0)
{
- opt_scale = std::min(0.008 + std::pow(ply + 3.0, 0.5) / 250.0,
- 0.2 * limits.time[us] / double(timeLeft));
- max_scale = 4 + std::min(36, ply) / 12.0;
+ optScale = std::min(0.0084 + std::pow(ply + 3.0, 0.5) * 0.0042,
+ 0.2 * limits.time[us] / double(timeLeft))
+ * optExtra;
+ maxScale = std::min(7.0, 4.0 + ply / 12.0);
}
// x moves in y seconds (+ z increment)
else
{
- opt_scale = std::min((0.8 + ply / 128.0) / mtg,
- 0.8 * limits.time[us] / double(timeLeft));
- max_scale = std::min(6.3, 1.5 + 0.11 * mtg);
+ optScale = std::min((0.88 + ply / 116.4) / mtg,
+ 0.88 * limits.time[us] / double(timeLeft));
+ maxScale = std::min(6.3, 1.5 + 0.11 * mtg);
}
// Never use more than 80% of the available time for this move
- optimumTime = std::max(minThinkingTime, TimePoint(opt_scale * timeLeft));
- maximumTime = TimePoint(std::min(0.8 * limits.time[us] - moveOverhead, max_scale * optimumTime));
+ optimumTime = TimePoint(optScale * timeLeft);
+ maximumTime = TimePoint(std::min(0.8 * limits.time[us] - moveOverhead, maxScale * optimumTime));
if (Options["Ponder"])
optimumTime += optimumTime / 4;
}
+
+} // namespace Stockfish