timeinfo.c

   1 #include <assert.h>
   2 #include <ctype.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <math.h>
   6 #include <time.h>
   7
   8 #define DEBUG
   9
  10 #include "debug.h"
  11 #include "timeinfo.h"
  12
  13 #define MAX_NET_LAG 2.0 /* Max net lag in seconds. TODO: estimate dynamically. */
  14 #define RESERVED_BYOYOMI_PERCENT 15 /* Reserve 15% of byoyomi time as safety margin if risk of losing on time */
  15
  16 /* For safety, use at most 3 times the desired time on a single move
  17  * in main time, and 1.1 times in byoyomi. */
  18 #define MAX_MAIN_TIME_EXTENSION 3.0
  19 #define MAX_BYOYOMI_TIME_EXTENSION 1.1
  20
  21 bool
  22 time_parse(struct time_info *ti, char *s)
  23 {
  24         switch (s[0]) {
  25                 case '_': ti->period = TT_TOTAL; s++; break;
  26                 default: ti->period = TT_MOVE; break;
  27         }
  28         switch (s[0]) {
  29                 case '=':
  30                         ti->dim = TD_GAMES;
  31                         ti->len.games = atoi(++s);
  32                         break;
  33                 default:
  34                         if (!isdigit(s[0]))
  35                                 return false;
  36                         ti->dim = TD_WALLTIME;
  37                         ti->len.t.main_time = atof(s);
  38                         ti->len.t.byoyomi_time = 0.0;
  39                         ti->len.t.byoyomi_periods = 0;
  40                         ti->len.t.timer_start = 0;
  41                         break;
  42         }
  43         return true;
  44 }
  45
  46 /* Update time settings according to gtp time_settings or kgs-time_settings command. */
  47 void
  48 time_settings(struct time_info *ti, int main_time, int byoyomi_time, int byoyomi_stones, int byoyomi_periods)
  49 {
  50         if (byoyomi_time > 0 && byoyomi_stones == 0) {
  51                 ti->period = TT_NULL; // no time limit, rely on engine default
  52         } else {
  53                 ti->period = TT_TOTAL;
  54                 ti->dim = TD_WALLTIME;
  55                 ti->len.t.main_time = (double) main_time;
  56                 ti->len.t.byoyomi_time = (double) byoyomi_time;
  57                 if (byoyomi_stones > 0)
  58                         ti->len.t.byoyomi_time /= byoyomi_stones;
  59                 ti->len.t.byoyomi_periods = byoyomi_periods;
  60                 ti->len.t.timer_start = 0;
  61         }
  62 }
  63
  64 /* Update time information according to gtp time_left command.
  65  * kgs doesn't give time_left for the first move, so make sure
  66  * that just time_settings + time_stop_conditions still work. */
  67 void
  68 time_left(struct time_info *ti, int time_left, int stones_left)
  69 {
  70         assert(ti->period != TT_NULL);
  71         ti->dim = TD_WALLTIME;
  72
  73         if (ti->len.t.byoyomi_periods > 0 && stones_left > 0) {
  74                 ti->len.t.byoyomi_periods = stones_left; // field misused by kgs
  75                 stones_left = 1;
  76         }
  77         if (stones_left == 0) {
  78                 /* Main time */
  79                 ti->period = TT_TOTAL;
  80                 ti->len.t.main_time = time_left;
  81                 /* byoyomi_time kept fully charged. */
  82         } else {
  83                 /* Byoyomi */
  84                 ti->period = TT_MOVE;
  85                 ti->len.t.main_time = 0;
  86                 ti->len.t.byoyomi_time = ((double)time_left)/stones_left;
  87                 /* XXX: We need to keep stones_left info in time_info
  88                  * to be able to deduce this in stop_conditions() instead. */
  89                 ti->len.t.max_time = time_left;
  90                 ti->len.t.recommended_time = ti->len.t.byoyomi_time;
  91         }
  92 }
  93
  94 /* Returns true if we are in byoyomi (or should play as if in byo yomi
  95  * because remaining time per move in main time is less than byoyomi time
  96  * per move). */
  97 bool
  98 time_in_byoyomi(struct time_info *ti) {
  99         return ti->period == TT_MOVE && ti->dim == TD_WALLTIME && ti->len.t.byoyomi_time > 0
 100                && ti->len.t.recommended_time <= ti->len.t.byoyomi_time + 0.001;
 101 }
 102
 103 /* Start our timer. kgs does this (correctly) on "play" not "genmove"
 104  * unless we are making the first move of the game. */
 105 void
 106 time_start_timer(struct time_info *ti)
 107 {
 108         if (ti->period != TT_NULL && ti->dim == TD_WALLTIME)
 109                 ti->len.t.timer_start = time_now();
 110 }
 111
 112 /* Returns the current time. */
 113 double
 114 time_now(void)
 115 {
 116         struct timespec now;
 117         clock_gettime(CLOCK_REALTIME, &now);
 118         return now.tv_sec + now.tv_nsec/1000000000.0;
 119 }
 120
 121 /* Sleep for a given interval (in seconds). Return immediately if interval < 0. */
 122 void
 123 time_sleep(double interval)
 124 {
 125         struct timespec ts;
 126         double sec;
 127         ts.tv_nsec = (int)(modf(interval, &sec)*1000000000.0);
 128         ts.tv_sec = (int)sec;
 129         nanosleep(&ts, NULL); /* ignore error if interval was < 0 */
 130 }
 131
 132
 133 /* Pre-process time_info for search control and sets the desired stopping conditions. */
 134 void
 135 time_stop_conditions(struct time_info *ti, struct board *b, int fuseki_end, int yose_start, struct time_stop *stop)
 136 {
 137         /* We must have _some_ limits by now, be it random default values! */
 138         assert(ti->period != TT_NULL);
 139
 140         /* Minimum net lag (seconds) to be reserved in the time for move. */
 141         double net_lag = MAX_NET_LAG;
 142
 143         /* Special-case limit by number of simulations. */
 144         if (ti->dim == TD_GAMES) {
 145                 if (ti->period == TT_TOTAL) {
 146                         ti->period = TT_MOVE;
 147                         ti->len.games /= board_estimated_moves_left(b);
 148                 }
 149
 150                 stop->desired.playouts = ti->len.games;
 151                 /* We force worst == desired, so note that we will NOT loop
 152                  * until best == winner. */
 153                 stop->worst.playouts = ti->len.games;
 154                 return;
 155         }
 156
 157         assert(ti->dim == TD_WALLTIME);
 158
 159
 160         /*** Transform @ti to TT_MOVE and set up recommended/max time and
 161          * net lag information. */
 162
 163         /* Make sure timer_start is set up, adjust net_lag. */
 164         double now = time_now();
 165         if (!ti->len.t.timer_start) {
 166                 ti->len.t.timer_start = now; // we're playing the first game move
 167         } else {
 168                 net_lag += now - ti->len.t.timer_start;
 169                 // TODO: keep statistics to get good estimate of lag not just current move
 170         }
 171
 172         /* Set up initial recommendations. */
 173         if (ti->len.t.main_time) {
 174                 ti->len.t.max_time = ti->len.t.recommended_time = ti->len.t.main_time;
 175         } // otherwise we have already set up max_, recommended_ in time_left().
 176
 177         if (ti->period == TT_TOTAL) {
 178                 int moves_left = board_estimated_moves_left(b);
 179                 if (ti->len.t.byoyomi_time > 0) {
 180                         /* For non-canadian byoyomi with N>1 periods, we use N-1 periods as main time,
 181                          * keeping the last one as insurance against unexpected net lag. */
 182                         if (ti->len.t.byoyomi_periods > 2) {
 183                                 ti->len.t.max_time += (ti->len.t.byoyomi_periods - 2) * ti->len.t.byoyomi_time;
 184                                 // Will add 1 more byoyomi_time just below
 185                         }
 186                         ti->len.t.max_time += ti->len.t.byoyomi_time;
 187                         ti->len.t.recommended_time = ti->len.t.max_time;
 188
 189                         /* Maximize the number of moves played uniformly in main time, while
 190                          * not playing faster in main time than in byoyomi. At this point,
 191                          * the main time remaining is ti->len.t.max_time and already includes
 192                          * the first (canadian) or N-1 byoyomi periods.
 193                          *    main_speed = max_time / main_moves >= byoyomi_time
 194                          * => main_moves <= max_time / byoyomi_time */
 195                         double actual_byoyomi = ti->len.t.byoyomi_time - net_lag;
 196                         if (actual_byoyomi > 0) {
 197                                 int main_moves = (int)(ti->len.t.max_time / actual_byoyomi);
 198                                 if (moves_left > main_moves)
 199                                         moves_left = main_moves; // will do the rest in byoyomi
 200                                 if (moves_left <= 0) // possible if too much lag
 201                                         moves_left = 1;
 202                         }
 203                 }
 204                 ti->period = TT_MOVE;
 205                 ti->len.t.recommended_time /= moves_left;
 206         }
 207         // To simplify the engine code, do not leave negative times:
 208         if (ti->len.t.recommended_time < 0)
 209                 ti->len.t.recommended_time = 0;
 210         if (ti->len.t.max_time < 0)
 211                 ti->len.t.max_time = 0;
 212         assert(ti->len.t.recommended_time <= ti->len.t.max_time + 0.001);
 213
 214         /* Use a larger safety margin if we risk losing on time on this move: */
 215         double safe_margin = RESERVED_BYOYOMI_PERCENT * ti->len.t.byoyomi_time/100;
 216         if (safe_margin > MAX_NET_LAG && ti->len.t.recommended_time >= ti->len.t.max_time - net_lag) {
 217                 net_lag = safe_margin;
 218         }
 219
 220         if (DEBUGL(1))
 221                 fprintf(stderr, "recommended_time %0.2f, max_time %0.2f, byoyomi %0.2f, lag %0.2f max %0.2f\n",
 222                         ti->len.t.recommended_time, ti->len.t.max_time, ti->len.t.byoyomi_time, net_lag,
 223                         net_lag);
 224
 225
 226         /*** Setup desired/worst time limits based on recommended/max time. */
 227
 228         assert(ti->period == TT_MOVE);
 229
 230         double desired_time = ti->len.t.recommended_time;
 231         double worst_time;
 232         if (time_in_byoyomi(ti)) {
 233                 // make recommended == average(desired, worst)
 234                 worst_time = desired_time * MAX_BYOYOMI_TIME_EXTENSION;
 235                 desired_time *= (2 - MAX_BYOYOMI_TIME_EXTENSION);
 236
 237         } else {
 238                 int bsize = (board_size(b)-2)*(board_size(b)-2);
 239                 fuseki_end = fuseki_end * bsize / 100; // move nb at fuseki end
 240                 yose_start = yose_start * bsize / 100; // move nb at yose start
 241                 assert(fuseki_end < yose_start);
 242
 243                 /* Before yose, spend some extra. */
 244                 if (b->moves < yose_start) {
 245                         int moves_to_yose = (yose_start - b->moves) / 2;
 246                         // ^- /2 because we only consider the moves we have to play ourselves
 247                         int left_at_yose_start = board_estimated_moves_left(b) - moves_to_yose;
 248                         if (left_at_yose_start < MIN_MOVES_LEFT)
 249                                 left_at_yose_start = MIN_MOVES_LEFT;
 250                         double longest_time = ti->len.t.max_time / left_at_yose_start;
 251                         if (longest_time < desired_time) {
 252                                 // Should rarely happen, but keep desired_time anyway
 253                         } else if (b->moves < fuseki_end) {
 254                                 assert(fuseki_end > 0);
 255                                 desired_time += ((longest_time - desired_time) * b->moves) / fuseki_end;
 256                         } else { assert(b->moves < yose_start);
 257                                 desired_time = longest_time;
 258                         }
 259                 }
 260                 worst_time = desired_time * MAX_MAIN_TIME_EXTENSION;
 261         }
 262         if (worst_time > ti->len.t.max_time)
 263                 worst_time = ti->len.t.max_time;
 264         if (desired_time > worst_time)
 265                 desired_time = worst_time;
 266
 267         stop->desired.time = ti->len.t.timer_start + desired_time - net_lag;
 268         stop->worst.time = ti->len.t.timer_start + worst_time - net_lag;
 269         // Both stop points may be in the past if too much lag.
 270
 271         if (DEBUGL(2))
 272                 fprintf(stderr, "desired time %.02f, worst %.02f\n", desired_time, worst_time);
 273 }