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.byoyomi_stones = 0;
  41                         ti->len.t.timer_start = 0;
  42                         break;
  43         }
  44         return true;
  45 }
  46
  47 /* Update time settings according to gtp time_settings or kgs-time_settings command. */
  48 void
  49 time_settings(struct time_info *ti, int main_time, int byoyomi_time, int byoyomi_stones, int byoyomi_periods)
  50 {
  51         if (byoyomi_time > 0 && byoyomi_stones == 0) {
  52                 ti->period = TT_NULL; // no time limit, rely on engine default
  53         } else {
  54                 ti->period = TT_TOTAL;
  55                 ti->dim = TD_WALLTIME;
  56                 ti->len.t.main_time = (double) main_time;
  57                 ti->len.t.byoyomi_time = (double) byoyomi_time;
  58                 ti->len.t.byoyomi_periods = byoyomi_periods > 1 ? byoyomi_periods : 1;
  59                 ti->len.t.byoyomi_stones = byoyomi_stones > 1 ? byoyomi_stones : 1;
  60                 ti->len.t.canadian = byoyomi_stones > 0;
  61                 ti->len.t.timer_start = 0;
  62         }
  63 }
  64
  65 /* Update time information according to gtp time_left command.
  66  * kgs doesn't give time_left for the first move, so make sure
  67  * that just time_settings + time_stop_conditions still work. */
  68 void
  69 time_left(struct time_info *ti, int time_left, int stones_left)
  70 {
  71         assert(ti->period != TT_NULL);
  72         ti->dim = TD_WALLTIME;
  73
  74         if (stones_left == 0) {
  75                 /* Main time */
  76                 ti->period = TT_TOTAL;
  77                 ti->len.t.main_time = time_left;
  78                 /* byoyomi_time kept fully charged. */
  79         } else {
  80                 /* Byoyomi */
  81                 ti->period = TT_MOVE;
  82                 ti->len.t.main_time = 0;
  83                 ti->len.t.byoyomi_time = time_left;
  84                 if (ti->len.t.canadian) {
  85                         ti->len.t.byoyomi_stones = stones_left;
  86                 } else {
  87                         // field misused by kgs
  88                         ti->len.t.byoyomi_periods = stones_left;
  89                 }
  90         }
  91 }
  92
  93 /* Returns true if we are in byoyomi (or should play as if in byo yomi
  94  * because remaining time per move in main time is less than byoyomi time
  95  * per move). */
  96 bool
  97 time_in_byoyomi(struct time_info *ti) {
  98         assert(ti->dim == TD_WALLTIME);
  99         if (!ti->len.t.byoyomi_time)
 100                 return false; // there is no byoyomi!
 101         assert(ti->len.t.byoyomi_stones > 0);
 102         if (!ti->len.t.main_time)
 103                 return true; // we _are_ in byoyomi
 104         if (ti->len.t.main_time <= ti->len.t.byoyomi_time / ti->len.t.byoyomi_stones + 0.001)
 105                 return true; // our basic time left is less than byoyomi time per move
 106         return false;
 107 }
 108
 109 /* Start our timer. kgs does this (correctly) on "play" not "genmove"
 110  * unless we are making the first move of the game. */
 111 void
 112 time_start_timer(struct time_info *ti)
 113 {
 114         if (ti->period != TT_NULL && ti->dim == TD_WALLTIME)
 115                 ti->len.t.timer_start = time_now();
 116 }
 117
 118 /* Returns the current time. */
 119 double
 120 time_now(void)
 121 {
 122         struct timespec now;
 123         clock_gettime(CLOCK_REALTIME, &now);
 124         return now.tv_sec + now.tv_nsec/1000000000.0;
 125 }
 126
 127 /* Sleep for a given interval (in seconds). Return immediately if interval < 0. */
 128 void
 129 time_sleep(double interval)
 130 {
 131         struct timespec ts;
 132         double sec;
 133         ts.tv_nsec = (int)(modf(interval, &sec)*1000000000.0);
 134         ts.tv_sec = (int)sec;
 135         nanosleep(&ts, NULL); /* ignore error if interval was < 0 */
 136 }
 137
 138
 139 /* Pre-process time_info for search control and sets the desired stopping conditions. */
 140 void
 141 time_stop_conditions(struct time_info *ti, struct board *b, int fuseki_end, int yose_start, struct time_stop *stop)
 142 {
 143         /* We must have _some_ limits by now, be it random default values! */
 144         assert(ti->period != TT_NULL);
 145
 146         /* Special-case limit by number of simulations. */
 147         if (ti->dim == TD_GAMES) {
 148                 if (ti->period == TT_TOTAL) {
 149                         ti->period = TT_MOVE;
 150                         ti->len.games /= board_estimated_moves_left(b);
 151                 }
 152
 153                 stop->desired.playouts = ti->len.games;
 154                 /* We force worst == desired, so note that we will NOT loop
 155                  * until best == winner. */
 156                 stop->worst.playouts = ti->len.games;
 157                 return;
 158         }
 159
 160         assert(ti->dim == TD_WALLTIME);
 161
 162
 163         /*** Transform @ti to TT_MOVE and set up recommended/max time and
 164          * net lag information. */
 165
 166
 167         /* Minimum net lag (seconds) to be reserved in the time for move. */
 168         double net_lag = MAX_NET_LAG;
 169         /* Make sure timer_start is set up, adjust net_lag. */
 170         if (!ti->len.t.timer_start) {
 171                 ti->len.t.timer_start = time_now(); // we're playing the first game move
 172         } else {
 173                 net_lag += time_now() - ti->len.t.timer_start;
 174                 // TODO: keep statistics to get good estimate of lag not just current move
 175         }
 176
 177         /* Absolute maximum time possible to spend on the move. */
 178         double max_time;
 179         /* Ideal/reasonable time to spend on the move. */
 180         double recommended_time;
 181         /* Set up initial recommendations. */
 182         if (!ti->len.t.main_time) {
 183                 max_time = ti->len.t.byoyomi_time;
 184                 assert(ti->len.t.byoyomi_stones > 0);
 185                 recommended_time = ti->len.t.byoyomi_time / ti->len.t.byoyomi_stones;
 186         } else {
 187                 max_time = recommended_time = ti->len.t.main_time;
 188         }
 189
 190         if (ti->period == TT_TOTAL) {
 191                 int moves_left = board_estimated_moves_left(b);
 192                 if (ti->len.t.byoyomi_time > 0) {
 193                         assert(ti->len.t.byoyomi_stones > 0);
 194                         /* Time for one move in byoyomi. */
 195                         double move_time = ti->len.t.byoyomi_time / ti->len.t.byoyomi_stones;
 196
 197                         /* For Japanese byoyomi with N>1 periods, we use N-1 periods as main time,
 198                          * keeping the last one as insurance against unexpected net lag. */
 199                         if (ti->len.t.byoyomi_periods > 2) {
 200                                 max_time += (ti->len.t.byoyomi_periods - 2) * move_time;
 201                                 // Will add 1 more byoyomi_time just below
 202                         }
 203                         max_time += move_time;
 204                         recommended_time = max_time;
 205
 206                         /* Maximize the number of moves played uniformly in main time, while
 207                          * not playing faster in main time than in byoyomi. At this point,
 208                          * the main time remaining is ti->len.t.max_time and already includes
 209                          * the first (canadian) or N-1 byoyomi periods.
 210                          *    main_speed = max_time / main_moves >= move_time
 211                          * => main_moves <= max_time / move_time */
 212                         double actual_byoyomi = move_time - net_lag;
 213                         if (actual_byoyomi > 0) {
 214                                 int main_moves = (int)(max_time / actual_byoyomi);
 215                                 if (moves_left > main_moves)
 216                                         moves_left = main_moves; // will do the rest in byoyomi
 217                                 if (moves_left <= 0) // possible if too much lag
 218                                         moves_left = 1;
 219                         }
 220                 }
 221                 ti->period = TT_MOVE;
 222                 recommended_time /= moves_left;
 223         }
 224         // To simplify the engine code, do not leave negative times:
 225         if (recommended_time < 0)
 226                 recommended_time = 0;
 227         if (max_time < 0)
 228                 max_time = 0;
 229         assert(recommended_time <= max_time + 0.001);
 230
 231         /* Use a larger safety margin if we risk losing on time on this move: */
 232         double safe_margin = RESERVED_BYOYOMI_PERCENT * ti->len.t.byoyomi_time/100;
 233         if (safe_margin > 0) {
 234                 assert(ti->len.t.byoyomi_stones > 0);
 235                 safe_margin /= ti->len.t.byoyomi_stones;
 236         }
 237         if (safe_margin > MAX_NET_LAG && recommended_time >= max_time - net_lag) {
 238                 net_lag = safe_margin;
 239         }
 240
 241         if (DEBUGL(1))
 242                 fprintf(stderr, "recommended_time %0.2f, max_time %0.2f, byoyomi %0.2f/%d, lag %0.2f\n",
 243                         recommended_time, max_time,
 244                         ti->len.t.byoyomi_time, ti->len.t.byoyomi_stones,
 245                         net_lag);
 246
 247
 248         /*** Setup desired/worst time limits based on recommended/max time. */
 249
 250         assert(ti->period == TT_MOVE);
 251
 252         double desired_time = recommended_time;
 253         double worst_time;
 254         if (time_in_byoyomi(ti)) {
 255                 // make recommended == average(desired, worst)
 256                 worst_time = desired_time * MAX_BYOYOMI_TIME_EXTENSION;
 257                 desired_time *= (2 - MAX_BYOYOMI_TIME_EXTENSION);
 258
 259         } else {
 260                 int bsize = (board_size(b)-2)*(board_size(b)-2);
 261                 fuseki_end = fuseki_end * bsize / 100; // move nb at fuseki end
 262                 yose_start = yose_start * bsize / 100; // move nb at yose start
 263                 assert(fuseki_end < yose_start);
 264
 265                 /* Before yose, spend some extra. */
 266                 if (b->moves < yose_start) {
 267                         int moves_to_yose = (yose_start - b->moves) / 2;
 268                         // ^- /2 because we only consider the moves we have to play ourselves
 269                         int left_at_yose_start = board_estimated_moves_left(b) - moves_to_yose;
 270                         if (left_at_yose_start < MIN_MOVES_LEFT)
 271                                 left_at_yose_start = MIN_MOVES_LEFT;
 272                         double longest_time = max_time / left_at_yose_start;
 273                         if (longest_time < desired_time) {
 274                                 // Should rarely happen, but keep desired_time anyway
 275                         } else if (b->moves < fuseki_end) {
 276                                 assert(fuseki_end > 0);
 277                                 desired_time += ((longest_time - desired_time) * b->moves) / fuseki_end;
 278                         } else { assert(b->moves < yose_start);
 279                                 desired_time = longest_time;
 280                         }
 281                 }
 282                 worst_time = desired_time * MAX_MAIN_TIME_EXTENSION;
 283         }
 284         if (worst_time > max_time)
 285                 worst_time = max_time;
 286         if (desired_time > worst_time)
 287                 desired_time = worst_time;
 288
 289         stop->desired.time = ti->len.t.timer_start + desired_time - net_lag;
 290         stop->worst.time = ti->len.t.timer_start + worst_time - net_lag;
 291         // Both stop points may be in the past if too much lag.
 292
 293         if (DEBUGL(2))
 294                 fprintf(stderr, "desired time %.02f, worst %.02f\n", desired_time, worst_time);
 295 }