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                         if (ti->period == TT_TOTAL) {
  38                                 ti->len.t.main_time = atof(s);
  39                                 ti->len.t.byoyomi_time = 0.0;
  40                                 ti->len.t.byoyomi_periods = 0;
  41                                 ti->len.t.byoyomi_stones = 0;
  42                         } else { assert(ti->period == TT_MOVE);
  43                                 ti->len.t.main_time = 0.0;
  44                                 ti->len.t.byoyomi_time = atof(s);
  45                                 ti->len.t.byoyomi_periods = 1;
  46                                 ti->len.t.byoyomi_stones = 1;
  47                         }
  48                         ti->len.t.timer_start = 0;
  49                         break;
  50         }
  51         return true;
  52 }
  53
  54 /* Update time settings according to gtp time_settings or kgs-time_settings command. */
  55 void
  56 time_settings(struct time_info *ti, int main_time, int byoyomi_time, int byoyomi_stones, int byoyomi_periods)
  57 {
  58         if (byoyomi_time > 0 && byoyomi_stones == 0) {
  59                 ti->period = TT_NULL; // no time limit, rely on engine default
  60         } else {
  61                 ti->period = TT_TOTAL;
  62                 ti->dim = TD_WALLTIME;
  63                 ti->len.t.main_time = (double) main_time;
  64                 ti->len.t.byoyomi_time = (double) byoyomi_time;
  65                 ti->len.t.byoyomi_periods = byoyomi_periods > 1 ? byoyomi_periods : 1;
  66                 ti->len.t.byoyomi_stones = byoyomi_stones > 1 ? byoyomi_stones : 1;
  67                 ti->len.t.canadian = byoyomi_stones > 0;
  68                 ti->len.t.timer_start = 0;
  69         }
  70 }
  71
  72 /* Update time information according to gtp time_left command.
  73  * kgs doesn't give time_left for the first move, so make sure
  74  * that just time_settings + time_stop_conditions still work. */
  75 void
  76 time_left(struct time_info *ti, int time_left, int stones_left)
  77 {
  78         assert(ti->period != TT_NULL);
  79         ti->dim = TD_WALLTIME;
  80
  81         if (stones_left == 0) {
  82                 /* Main time */
  83                 ti->period = TT_TOTAL;
  84                 ti->len.t.main_time = time_left;
  85                 /* byoyomi_time kept fully charged. */
  86         } else {
  87                 /* Byoyomi */
  88                 ti->period = TT_MOVE;
  89                 ti->len.t.main_time = 0;
  90                 ti->len.t.byoyomi_time = time_left;
  91                 if (ti->len.t.canadian) {
  92                         ti->len.t.byoyomi_stones = stones_left;
  93                 } else {
  94                         // field misused by kgs
  95                         ti->len.t.byoyomi_periods = stones_left;
  96                 }
  97         }
  98 }
  99
 100 /* Returns true if we are in byoyomi (or should play as if in byo yomi
 101  * because remaining time per move in main time is less than byoyomi time
 102  * per move). */
 103 bool
 104 time_in_byoyomi(struct time_info *ti) {
 105         assert(ti->dim == TD_WALLTIME);
 106         if (!ti->len.t.byoyomi_time)
 107                 return false; // there is no byoyomi!
 108         assert(ti->len.t.byoyomi_stones > 0);
 109         if (!ti->len.t.main_time)
 110                 return true; // we _are_ in byoyomi
 111         if (ti->len.t.main_time <= ti->len.t.byoyomi_time / ti->len.t.byoyomi_stones + 0.001)
 112                 return true; // our basic time left is less than byoyomi time per move
 113         return false;
 114 }
 115
 116 /* Start our timer. kgs does this (correctly) on "play" not "genmove"
 117  * unless we are making the first move of the game. */
 118 void
 119 time_start_timer(struct time_info *ti)
 120 {
 121         if (ti->period != TT_NULL && ti->dim == TD_WALLTIME)
 122                 ti->len.t.timer_start = time_now();
 123 }
 124
 125 /* Returns the current time. */
 126 double
 127 time_now(void)
 128 {
 129         struct timespec now;
 130         clock_gettime(CLOCK_REALTIME, &now);
 131         return now.tv_sec + now.tv_nsec/1000000000.0;
 132 }
 133
 134 /* Sleep for a given interval (in seconds). Return immediately if interval < 0. */
 135 void
 136 time_sleep(double interval)
 137 {
 138         struct timespec ts;
 139         double sec;
 140         ts.tv_nsec = (int)(modf(interval, &sec)*1000000000.0);
 141         ts.tv_sec = (int)sec;
 142         nanosleep(&ts, NULL); /* ignore error if interval was < 0 */
 143 }
 144
 145
 146 /* Pre-process time_info for search control and sets the desired stopping conditions. */
 147 void
 148 time_stop_conditions(struct time_info *ti, struct board *b, int fuseki_end, int yose_start, struct time_stop *stop)
 149 {
 150         /* We must have _some_ limits by now, be it random default values! */
 151         assert(ti->period != TT_NULL);
 152
 153         /* Special-case limit by number of simulations. */
 154         if (ti->dim == TD_GAMES) {
 155                 if (ti->period == TT_TOTAL) {
 156                         ti->period = TT_MOVE;
 157                         ti->len.games /= board_estimated_moves_left(b);
 158                 }
 159
 160                 stop->desired.playouts = ti->len.games;
 161                 /* We force worst == desired, so note that we will NOT loop
 162                  * until best == winner. */
 163                 stop->worst.playouts = ti->len.games;
 164                 return;
 165         }
 166
 167         assert(ti->dim == TD_WALLTIME);
 168
 169
 170         /*** Transform @ti to TT_MOVE and set up recommended/max time and
 171          * net lag information. */
 172
 173
 174         /* Minimum net lag (seconds) to be reserved in the time for move. */
 175         double net_lag = MAX_NET_LAG;
 176         /* Make sure timer_start is set up, adjust net_lag. */
 177         if (!ti->len.t.timer_start) {
 178                 ti->len.t.timer_start = time_now(); // we're playing the first game move
 179         } else {
 180                 net_lag += time_now() - ti->len.t.timer_start;
 181                 // TODO: keep statistics to get good estimate of lag not just current move
 182         }
 183
 184         /* Absolute maximum time possible to spend on the move. */
 185         double max_time;
 186         /* Ideal/reasonable time to spend on the move. */
 187         double recommended_time;
 188         /* Set up initial recommendations. */
 189         if (!ti->len.t.main_time) {
 190                 max_time = ti->len.t.byoyomi_time;
 191                 assert(ti->len.t.byoyomi_stones > 0);
 192                 recommended_time = ti->len.t.byoyomi_time / ti->len.t.byoyomi_stones;
 193         } else {
 194                 max_time = recommended_time = ti->len.t.main_time;
 195         }
 196
 197         if (ti->period == TT_TOTAL) {
 198                 int moves_left = board_estimated_moves_left(b);
 199                 if (ti->len.t.byoyomi_time > 0) {
 200                         assert(ti->len.t.byoyomi_stones > 0);
 201                         /* Time for one move in byoyomi. */
 202                         double move_time = ti->len.t.byoyomi_time / ti->len.t.byoyomi_stones;
 203
 204                         /* For Japanese byoyomi with N>1 periods, we use N-1 periods as main time,
 205                          * keeping the last one as insurance against unexpected net lag. */
 206                         if (ti->len.t.byoyomi_periods > 2) {
 207                                 max_time += (ti->len.t.byoyomi_periods - 2) * move_time;
 208                                 // Will add 1 more byoyomi_time just below
 209                         }
 210                         max_time += move_time;
 211                         recommended_time = max_time;
 212
 213                         /* Maximize the number of moves played uniformly in main time, while
 214                          * not playing faster in main time than in byoyomi. At this point,
 215                          * the main time remaining is ti->len.t.max_time and already includes
 216                          * the first (canadian) or N-1 byoyomi periods.
 217                          *    main_speed = max_time / main_moves >= move_time
 218                          * => main_moves <= max_time / move_time */
 219                         double actual_byoyomi = move_time - net_lag;
 220                         if (actual_byoyomi > 0) {
 221                                 int main_moves = (int)(max_time / actual_byoyomi);
 222                                 if (moves_left > main_moves)
 223                                         moves_left = main_moves; // will do the rest in byoyomi
 224                                 if (moves_left <= 0) // possible if too much lag
 225                                         moves_left = 1;
 226                         }
 227                 }
 228                 ti->period = TT_MOVE;
 229                 recommended_time /= moves_left;
 230         }
 231         // To simplify the engine code, do not leave negative times:
 232         if (recommended_time < 0)
 233                 recommended_time = 0;
 234         if (max_time < 0)
 235                 max_time = 0;
 236         assert(recommended_time <= max_time + 0.001);
 237
 238         /* Use a larger safety margin if we risk losing on time on this move: */
 239         double safe_margin = RESERVED_BYOYOMI_PERCENT * ti->len.t.byoyomi_time/100;
 240         if (safe_margin > 0) {
 241                 assert(ti->len.t.byoyomi_stones > 0);
 242                 safe_margin /= ti->len.t.byoyomi_stones;
 243         }
 244         if (safe_margin > MAX_NET_LAG && recommended_time >= max_time - net_lag) {
 245                 net_lag = safe_margin;
 246         }
 247
 248         if (DEBUGL(1))
 249                 fprintf(stderr, "recommended_time %0.2f, max_time %0.2f, byoyomi %0.2f/%d, lag %0.2f\n",
 250                         recommended_time, max_time,
 251                         ti->len.t.byoyomi_time, ti->len.t.byoyomi_stones,
 252                         net_lag);
 253
 254
 255         /*** Setup desired/worst time limits based on recommended/max time. */
 256
 257         assert(ti->period == TT_MOVE);
 258
 259         double desired_time = recommended_time;
 260         double worst_time;
 261         if (time_in_byoyomi(ti)) {
 262                 // make recommended == average(desired, worst)
 263                 worst_time = desired_time * MAX_BYOYOMI_TIME_EXTENSION;
 264                 desired_time *= (2 - MAX_BYOYOMI_TIME_EXTENSION);
 265
 266         } else {
 267                 int bsize = (board_size(b)-2)*(board_size(b)-2);
 268                 fuseki_end = fuseki_end * bsize / 100; // move nb at fuseki end
 269                 yose_start = yose_start * bsize / 100; // move nb at yose start
 270                 assert(fuseki_end < yose_start);
 271
 272                 /* Before yose, spend some extra. */
 273                 if (b->moves < yose_start) {
 274                         int moves_to_yose = (yose_start - b->moves) / 2;
 275                         // ^- /2 because we only consider the moves we have to play ourselves
 276                         int left_at_yose_start = board_estimated_moves_left(b) - moves_to_yose;
 277                         if (left_at_yose_start < MIN_MOVES_LEFT)
 278                                 left_at_yose_start = MIN_MOVES_LEFT;
 279                         double longest_time = max_time / left_at_yose_start;
 280                         if (longest_time < desired_time) {
 281                                 // Should rarely happen, but keep desired_time anyway
 282                         } else if (b->moves < fuseki_end) {
 283                                 assert(fuseki_end > 0);
 284                                 desired_time += ((longest_time - desired_time) * b->moves) / fuseki_end;
 285                         } else { assert(b->moves < yose_start);
 286                                 desired_time = longest_time;
 287                         }
 288                 }
 289                 worst_time = desired_time * MAX_MAIN_TIME_EXTENSION;
 290         }
 291         if (worst_time > max_time)
 292                 worst_time = max_time;
 293         if (desired_time > worst_time)
 294                 desired_time = worst_time;
 295
 296         stop->desired.time = ti->len.t.timer_start + desired_time - net_lag;
 297         stop->worst.time = ti->len.t.timer_start + worst_time - net_lag;
 298         // Both stop points may be in the past if too much lag.
 299
 300         if (DEBUGL(2))
 301                 fprintf(stderr, "desired time %.02f, worst %.02f\n", desired_time, worst_time);
 302 }