1 /* This is a master for the "distributed" engine. It receives connections
2 * from slave machines, sends them gtp commands, then aggregates the
3 * results. It can also act as a proxy for the logs of all slave machines.
4 * The slave machines must run with engine "uct" (not "distributed").
5 * The master sends pachi-genmoves gtp commands regularly to each slave,
6 * gets as replies a list of nodes, their number of playouts
7 * and their value. The master then picks the most popular move
8 * among the top level nodes. */
10 /* With time control, the master waits for all slaves, except
11 * when the allowed time is already passed. In this case the
12 * master picks among the available replies, or waits for just
13 * one reply if there is none yet.
14 * Without time control, the master waits until the desired
15 * number of games have been simulated. In this case the -t
16 * parameter for the master should be the sum of the parameters
19 /* The master sends updated statistics for the best nodes in each
20 * genmoves command. They are incremental updates from all other
21 * slaves (so they exclude contributions from the target slave).
22 * The slaves reply with just their own stats. So both master and
23 * slave remember what was previously sent. A slave remembers in
24 * the tree ("pu" field), which is stable across moves. The slave
25 * also has a temporary hash table to map received coord paths
26 * to tree nodes; the hash table is cleared at each new move.
27 * The master remembers stats in a queue of received buffers that
28 * are merged together, plus one hash table per slave. The master
29 * queue and the hash tables are cleared at each new move. */
31 /* To allow the master to select the best move, slaves also send
32 * absolute playout counts for the best top level nodes (children
33 * of the root node), including contributions from other slaves.
34 * The master sums these counts and picks the best sum, which is
35 * equivalent to picking the best average. (The master cannot
36 * use the incremental stats sent in binary form because they
37 * are not maintained across moves, so playouts from previous
38 * moves would be lost.) */
40 /* The master-slave protocol has fault tolerance. If a slave is
41 * out of sync, the master sends it the appropriate command history. */
43 /* Pass me arguments like a=b,c=d,...
44 * Supported arguments:
45 * slave_port=SLAVE_PORT slaves connect to this port; this parameter is mandatory.
46 * max_slaves=MAX_SLAVES default 24
47 * shared_nodes=SHARED_NODES default 10K
48 * stats_hbits=STATS_HBITS default 21. 2^stats_bits = hash table size
49 * slaves_quit=0|1 quit gtp command also sent to slaves, default false.
50 * proxy_port=PROXY_PORT slaves optionally send their logs to this port.
51 * Warning: with proxy_port, the master stderr mixes the logs of all
52 * machines but you can separate them again:
53 * slave logs: sed -n '/< .*:/s/.*< /< /p' logfile
54 * master logs: perl -0777 -pe 's/<[ <].*:.*\n//g' logfile
57 /* A configuration without proxy would have one master run on masterhost as:
58 * zzgo -e distributed slave_port=1234
59 * and N slaves running as:
60 * zzgo -e uct -g masterhost:1234 slave
62 * zzgo -e distributed slave_port=1234,proxy_port=1235
63 * zzgo -e uct -g masterhost:1234 -l masterhost:1235 slave
64 * If the master itself runs on a machine other than that running gogui,
65 * gogui-twogtp, kgsGtp or cgosGtp, it can redirect its gtp port:
66 * zzgo -e distributed -g 10000 slave_port=1234,proxy_port=1235
75 #include <sys/types.h>
86 #include "distributed/distributed.h"
87 #include "distributed/merge.h"
89 /* Internal engine state. */
97 struct move my_last_move
;
98 struct move_stats my_last_stats
;
101 /* Default number of simulations to perform per move.
102 * Note that this is in total over all slaves! */
103 #define DIST_GAMES 80000
104 static const struct time_info default_ti
= {
107 .len
= { .games
= DIST_GAMES
},
110 #define get_value(value, color) \
111 ((color) == S_BLACK ? (value) : 1 - (value))
114 /* Maximum time (seconds) to wait for answers to fast gtp commands
115 * (all commands except pachi-genmoves and final_status_list). */
116 #define MAX_FAST_CMD_WAIT 1.0
118 /* Maximum time (seconds) to wait for answers to genmoves. */
119 #define MAX_GENMOVES_WAIT 0.1 /* 100 ms */
121 /* Minimum time (seconds) to wait before we stop early. This should
122 * ensure that most slaves have replied at least once. */
123 #define MIN_EARLY_STOP_WAIT 0.3 /* 300 ms */
125 /* Display a path as leaf<parent<grandparent...
126 * Returns the path string in a static buffer; it is NOT safe for
127 * anything but debugging - in particular, it is NOT thread-safe! */
129 path2sstr(path_t path
, struct board
*b
)
131 /* Special case for pass and resign. */
132 if (path
< 0) return coord2sstr((coord_t
)path
, b
);
134 static char buf
[16][64];
142 while ((leaf
= leaf_coord(path
, b
)) != 0) {
143 s
+= snprintf(s
, end
- s
, "%s<", coord2sstr(leaf
, b
));
144 path
= parent_path(path
, b
);
146 if (s
!= b2
) s
[-1] = '\0';
150 /* Dispatch a new gtp command to all slaves.
151 * The slave lock must not be held upon entry and is released upon return.
152 * args is empty or ends with '\n' */
153 static enum parse_code
154 distributed_notify(struct engine
*e
, struct board
*b
, int id
, char *cmd
, char *args
, char **reply
)
156 struct distributed
*dist
= e
->data
;
158 /* Commands that should not be sent to slaves.
159 * time_left will be part of next pachi-genmoves,
160 * we reduce latency by not forwarding it here. */
161 if ((!strcasecmp(cmd
, "quit") && !dist
->slaves_quit
)
162 || !strcasecmp(cmd
, "uct_gentbook")
163 || !strcasecmp(cmd
, "uct_dumptbook")
164 || !strcasecmp(cmd
, "kgs-chat")
165 || !strcasecmp(cmd
, "time_left")
167 /* and commands that will be sent to slaves later */
168 || !strcasecmp(cmd
, "genmove")
169 || !strcasecmp(cmd
, "kgs-genmove_cleanup")
170 || !strcasecmp(cmd
, "final_score")
171 || !strcasecmp(cmd
, "final_status_list"))
176 // Create a new command to be sent by the slave threads.
177 new_cmd(b
, cmd
, args
);
179 /* Wait for replies here. If we don't wait, we run the
180 * risk of getting out of sync with most slaves and
181 * sending command history too frequently. */
182 get_replies(time_now() + MAX_FAST_CMD_WAIT
, active_slaves
);
188 /* genmoves returns "=id played_own total_playouts threads keep_looking @size"
189 * then a list of lines "coord playouts value" with absolute counts for
190 * children of the root node, then a binary array of incr_stats structs.
191 * To simplify the code, we assume that master and slave have the same architecture
192 * (store values identically).
193 * Return the move with most playouts, and additional stats.
194 * keep_looking is set from a majority vote of the slaves seen so far for this
195 * move but should not be trusted if too few slaves have been seen.
196 * Keep this code in sync with uct/slave.c:report_stats().
197 * slave_lock is held on entry and on return. */
199 select_best_move(struct board
*b
, struct move_stats
*stats
, int *played
,
200 int *total_playouts
, int *total_threads
, bool *keep_looking
)
202 assert(reply_count
> 0);
204 /* +2 for pass and resign */
205 memset(stats
-2, 0, (board_size2(b
)+2) * sizeof(*stats
));
207 coord_t best_move
= pass
;
208 int best_playouts
= -1;
214 for (int reply
= 0; reply
< reply_count
; reply
++) {
215 char *r
= gtp_replies
[reply
];
217 if (sscanf(r
, "=%d %d %d %d %d", &id
, &o
, &p
, &t
, &k
) != 5) continue;
219 *total_playouts
+= p
;
222 // Skip the rest of the firt line in particular @size
227 while (r
&& sscanf(++r
, "%63s %d " PRIfloating
, move
, &s
.playouts
, &s
.value
) == 3) {
228 coord_t c
= str2scoord(move
, board_size(b
));
229 assert (c
>= resign
&& c
< board_size2(b
) && s
.playouts
>= 0);
231 stats_add_result(&stats
[c
], s
.value
, s
.playouts
);
233 if (stats
[c
].playouts
> best_playouts
) {
234 best_playouts
= stats
[c
].playouts
;
240 *keep_looking
= keep
> reply_count
/ 2;
244 /* Set the args for the genmoves command. If binary_args is set,
245 * each slave thred will add the correct binary size when sending
246 * (see get_binary_arg()). args must have CMDS_SIZE bytes and
247 * upon return ends with a single \n.
248 * Keep this code in sync with uct/slave.c:uct_genmoves().
249 * slave_lock is held on entry and on return but we don't
250 * rely on the lock here. */
252 genmoves_args(char *args
, enum stone color
, int played
,
253 struct time_info
*ti
, bool binary_args
)
255 char *end
= args
+ CMDS_SIZE
;
256 char *s
= args
+ snprintf(args
, CMDS_SIZE
, "%s %d", stone2str(color
), played
);
258 if (ti
->dim
== TD_WALLTIME
) {
259 s
+= snprintf(s
, end
- s
, " %.3f %.3f %d %d",
260 ti
->len
.t
.main_time
, ti
->len
.t
.byoyomi_time
,
261 ti
->len
.t
.byoyomi_periods
, ti
->len
.t
.byoyomi_stones
);
263 s
+= snprintf(s
, end
- s
, binary_args
? " @0\n" : "\n");
266 /* Time control is mostly done by the slaves, so we use default values here. */
267 #define FUSEKI_END 20
268 #define YOSE_START 40
269 #define MAX_MAINTIME_RATIO 3.0
271 /* In the ascii reply to genmoves, each slave sends absolute counts
272 * including contributions from other slaves. For human display
273 * reduce the sum to an average. */
274 #define stats_average(playouts) ((playouts) / reply_count)
276 /* Regularly send genmoves command to the slaves, and select the best move. */
278 distributed_genmove(struct engine
*e
, struct board
*b
, struct time_info
*ti
,
279 enum stone color
, bool pass_all_alive
)
281 struct distributed
*dist
= e
->data
;
282 double now
= time_now();
284 char buf
[BSIZE
]; // debug only
286 char *cmd
= pass_all_alive
? "pachi-genmoves_cleanup" : "pachi-genmoves";
287 char args
[CMDS_SIZE
];
290 int played
, playouts
, threads
;
292 if (ti
->period
== TT_NULL
) *ti
= default_ti
;
293 struct time_stop stop
;
294 time_stop_conditions(ti
, b
, FUSEKI_END
, YOSE_START
, MAX_MAINTIME_RATIO
, &stop
);
295 struct time_info saved_ti
= *ti
;
297 /* Combined move stats from all slaves, only for children
298 * of the root node, plus 2 for pass and resign. */
299 struct move_stats
*stats
= alloca((board_size2(b
)+2) * sizeof(struct move_stats
));
303 clear_receive_queue();
305 /* Send the first genmoves without stats. */
306 genmoves_args(args
, color
, 0, ti
, false);
307 new_cmd(b
, cmd
, args
);
309 /* Loop until most slaves want to quit or time elapsed. */
311 for (iterations
= 1; ; iterations
++) {
313 /* Wait for just one slave to get stats as fresh as possible,
314 * or at most 100ms to check if we run out of time. */
315 get_replies(now
+ MAX_GENMOVES_WAIT
, 1);
317 if (ti
->dim
== TD_WALLTIME
)
318 time_sub(ti
, now
- start
, false);
321 best
= select_best_move(b
, stats
, &played
, &playouts
, &threads
, &keep_looking
);
323 if (ti
->dim
== TD_WALLTIME
) {
324 if (now
- ti
->len
.t
.timer_start
>= stop
.worst
.time
) break;
325 if (!keep_looking
&& now
- first
>= MIN_EARLY_STOP_WAIT
) break;
327 if (!keep_looking
|| played
>= stop
.worst
.playouts
) break;
330 char *coord
= coord2sstr(best
, b
);
331 snprintf(buf
, sizeof(buf
),
332 "temp winner is %s %s with score %1.4f (%d/%d games)"
333 " %d slaves %d threads\n",
334 stone2str(color
), coord
, get_value(stats
[best
].value
, color
),
335 stats_average(stats
[best
].playouts
), playouts
, reply_count
, threads
);
336 logline(NULL
, "* ", buf
);
338 /* Send the command with the same gtp id, to avoid discarding
339 * a reply to a previous genmoves at the same move. */
340 genmoves_args(args
, color
, played
, ti
, true);
341 update_cmd(b
, cmd
, args
, false);
343 int replies
= reply_count
;
345 /* Do not subtract time spent twice (see gtp_parse). */
348 dist
->my_last_move
.color
= color
;
349 dist
->my_last_move
.coord
= best
;
350 dist
->my_last_stats
.value
= stats
[best
].value
;
351 dist
->my_last_stats
.playouts
= stats_average(stats
[best
].playouts
);
353 /* Tell the slaves to commit to the selected move, overwriting
354 * the last "pachi-genmoves" in the command history. */
355 clear_receive_queue();
357 char *coord
= coord2bstr(coordbuf
, best
, b
);
358 snprintf(args
, sizeof(args
), "%s %s\n", stone2str(color
), coord
);
359 update_cmd(b
, "play", args
, true);
363 double time
= now
- first
+ 0.000001; /* avoid divide by zero */
364 snprintf(buf
, sizeof(buf
),
365 "GLOBAL WINNER is %s %s with score %1.4f (%d/%d games)\n"
366 "genmove %d games in %0.2fs %d slaves %d threads (%d games/s,"
367 " %d games/s/slave, %d games/s/thread, %.3f ms/iter)\n",
368 stone2str(color
), coord
, get_value(stats
[best
].value
, color
),
369 stats
[best
].playouts
, playouts
, played
, time
, replies
, threads
,
370 (int)(played
/time
), (int)(played
/time
/replies
),
371 (int)(played
/time
/threads
), 1000*time
/iterations
);
372 logline(NULL
, "* ", buf
);
375 int total_hnodes
= replies
* (1 << dist
->stats_hbits
);
376 merge_print_stats(total_hnodes
);
378 return coord_copy(best
);
382 distributed_chat(struct engine
*e
, struct board
*b
, char *cmd
)
384 struct distributed
*dist
= e
->data
;
385 static char reply
[BSIZE
];
387 cmd
+= strspn(cmd
, " \n\t");
388 if (!strncasecmp(cmd
, "winrate", 7)) {
389 enum stone color
= dist
->my_last_move
.color
;
390 snprintf(reply
, BSIZE
, "In %d playouts at %d machines, %s %s can win with %.2f%% probability.",
391 dist
->my_last_stats
.playouts
, active_slaves
, stone2str(color
),
392 coord2sstr(dist
->my_last_move
.coord
, b
),
393 100 * get_value(dist
->my_last_stats
.value
, color
));
400 scmp(const void *p1
, const void *p2
)
402 return strcasecmp(*(char * const *)p1
, *(char * const *)p2
);
406 distributed_dead_group_list(struct engine
*e
, struct board
*b
, struct move_queue
*mq
)
410 new_cmd(b
, "final_status_list", "dead\n");
411 get_replies(time_now() + MAX_FAST_CMD_WAIT
, active_slaves
);
413 /* Find the most popular reply. */
414 qsort(gtp_replies
, reply_count
, sizeof(char *), scmp
);
418 for (int reply
= 1; reply
< reply_count
; reply
++) {
419 if (!strcmp(gtp_replies
[reply
], gtp_replies
[reply
-1])) {
424 if (count
> best_count
) {
430 /* Pick the first move of each line as group. */
431 char *dead
= gtp_replies
[best_reply
];
432 dead
= strchr(dead
, ' '); // skip "id "
433 while (dead
&& *++dead
!= '\n') {
434 mq_add(mq
, str2scoord(dead
, board_size(b
)), 0);
435 dead
= strchr(dead
, '\n');
440 static struct distributed
*
441 distributed_state_init(char *arg
, struct board
*b
)
443 struct distributed
*dist
= calloc2(1, sizeof(struct distributed
));
445 dist
->stats_hbits
= DEFAULT_STATS_HBITS
;
446 dist
->max_slaves
= DEFAULT_MAX_SLAVES
;
447 dist
->shared_nodes
= DEFAULT_SHARED_NODES
;
449 char *optspec
, *next
= arg
;
452 next
+= strcspn(next
, ",");
453 if (*next
) { *next
++ = 0; } else { *next
= 0; }
455 char *optname
= optspec
;
456 char *optval
= strchr(optspec
, '=');
457 if (optval
) *optval
++ = 0;
459 if (!strcasecmp(optname
, "slave_port") && optval
) {
460 dist
->slave_port
= strdup(optval
);
461 } else if (!strcasecmp(optname
, "proxy_port") && optval
) {
462 dist
->proxy_port
= strdup(optval
);
463 } else if (!strcasecmp(optname
, "max_slaves") && optval
) {
464 dist
->max_slaves
= atoi(optval
);
465 } else if (!strcasecmp(optname
, "shared_nodes") && optval
) {
466 /* Share at most shared_nodes between master and slave at each genmoves.
467 * Must use the same value in master and slaves. */
468 dist
->shared_nodes
= atoi(optval
);
469 } else if (!strcasecmp(optname
, "stats_hbits") && optval
) {
470 /* Set hash table size to 2^stats_hbits for the shared stats. */
471 dist
->stats_hbits
= atoi(optval
);
472 } else if (!strcasecmp(optname
, "slaves_quit")) {
473 dist
->slaves_quit
= !optval
|| atoi(optval
);
475 fprintf(stderr
, "distributed: Invalid engine argument %s or missing value\n", optname
);
480 gtp_replies
= calloc2(dist
->max_slaves
, sizeof(char *));
482 if (!dist
->slave_port
) {
483 fprintf(stderr
, "distributed: missing slave_port\n");
487 merge_init(&default_sstate
, dist
->shared_nodes
, dist
->stats_hbits
, dist
->max_slaves
);
488 protocol_init(dist
->slave_port
, dist
->proxy_port
, dist
->max_slaves
);
494 engine_distributed_init(char *arg
, struct board
*b
)
496 struct distributed
*dist
= distributed_state_init(arg
, b
);
497 struct engine
*e
= calloc2(1, sizeof(struct engine
));
498 e
->name
= "Distributed Engine";
499 e
->comment
= "I'm playing the distributed engine. When I'm losing, I will resign, "
500 "if I think I win, I play until you pass. "
501 "Anyone can send me 'winrate' in private chat to get my assessment of the position.";
502 e
->notify
= distributed_notify
;
503 e
->genmove
= distributed_genmove
;
504 e
->dead_group_list
= distributed_dead_group_list
;
505 e
->chat
= distributed_chat
;
507 // Keep the threads and the open socket connections:
508 e
->keep_on_clear
= true;