2 * PgBouncer - Lightweight connection pooler for PostgreSQL.
4 * Copyright (c) 2007-2009 Marko Kreen, Skype Technologies OÜ
6 * Permission to use, copy, modify, and/or distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 * Periodic maintenance.
25 /* do full maintenance 3x per second */
26 static struct timeval full_maint_period = {0, USEC / 3};
27 static struct event full_maint_ev;
29 /* close all sockets in server list */
30 static void close_server_list(StatList *sk_list, const char *reason)
35 statlist_for_each_safe(item, sk_list, tmp) {
36 server = container_of(item, PgSocket, head);
37 disconnect_server(server, true, reason);
41 static void close_client_list(StatList *sk_list, const char *reason)
46 statlist_for_each_safe(item, sk_list, tmp) {
47 client = container_of(item, PgSocket, head);
48 disconnect_client(client, true, reason);
52 bool suspend_socket(PgSocket *sk, bool force_suspend)
57 if (sbuf_is_empty(&sk->sbuf)) {
58 if (sbuf_pause(&sk->sbuf))
62 if (sk->suspended || !force_suspend)
65 if (is_server_socket(sk))
66 disconnect_server(sk, true, "suspend_timeout");
68 disconnect_client(sk, true, "suspend_timeout");
72 /* suspend all sockets in socket list */
73 static int suspend_socket_list(StatList *list, bool force_suspend)
79 statlist_for_each_safe(item, list, tmp) {
80 sk = container_of(item, PgSocket, head);
81 if (!suspend_socket(sk, force_suspend))
87 /* resume all suspended sockets in socket list */
88 static void resume_socket_list(StatList *list)
93 statlist_for_each_safe(item, list, tmp) {
94 sk = container_of(item, PgSocket, head);
97 sbuf_continue(&sk->sbuf);
102 /* resume all suspended sockets in all pools */
103 static void resume_sockets(void)
108 statlist_for_each(item, &pool_list) {
109 pool = container_of(item, PgPool, head);
112 resume_socket_list(&pool->active_client_list);
113 resume_socket_list(&pool->active_server_list);
114 resume_socket_list(&pool->idle_server_list);
115 resume_socket_list(&pool->used_server_list);
119 /* resume pools and listen sockets */
120 void resume_all(void)
127 * send test/reset query to server if needed
129 static void launch_recheck(PgPool *pool)
131 const char *q = cf_server_check_query;
132 bool need_check = true;
136 /* find clean server */
138 server = first_socket(&pool->used_server_list);
143 disconnect_server(server, true, "idle server got dirty");
146 /* is the check needed? */
147 if (q == NULL || q[0] == 0)
149 else if (cf_server_check_delay > 0) {
150 usec_t now = get_cached_time();
151 if (now - server->request_time < cf_server_check_delay)
156 /* send test query, wait for result */
157 slog_debug(server, "P: Checking: %s", q);
158 change_server_state(server, SV_TESTED);
159 SEND_generic(res, server, 'Q', "s", q);
161 disconnect_server(server, false, "test query failed");
163 /* make immediately available */
164 release_server(server);
168 * make servers available
170 static void per_loop_activate(PgPool *pool)
175 /* see if any server have been freed */
176 statlist_for_each_safe(item, &pool->waiting_client_list, tmp) {
177 client = container_of(item, PgSocket, head);
178 if (!statlist_empty(&pool->idle_server_list)) {
180 /* db not fully initialized after reboot */
181 if (client->wait_for_welcome && !pool->welcome_msg_ready) {
182 launch_new_connection(pool);
186 /* there is a ready server already */
187 activate_client(client);
188 } else if (!statlist_empty(&pool->tested_server_list)) {
189 /* some connections are in testing process */
191 } else if (!statlist_empty(&pool->used_server_list)) {
192 /* ask for more connections to be tested */
193 launch_recheck(pool);
196 /* not enough connections */
197 launch_new_connection(pool);
204 * pause active clients
206 static int per_loop_pause(PgPool *pool)
213 close_server_list(&pool->idle_server_list, "pause mode");
214 close_server_list(&pool->used_server_list, "pause mode");
215 close_server_list(&pool->new_server_list, "pause mode");
217 active += statlist_count(&pool->active_server_list);
218 active += statlist_count(&pool->tested_server_list);
224 * suspend active clients and servers
226 static int per_loop_suspend(PgPool *pool, bool force_suspend)
233 active += suspend_socket_list(&pool->active_client_list, force_suspend);
235 /* this list is unsuspendable, but still need force_suspend and counting */
236 active += suspend_socket_list(&pool->waiting_client_list, force_suspend);
238 per_loop_activate(pool);
241 active += suspend_socket_list(&pool->active_server_list, force_suspend);
242 active += suspend_socket_list(&pool->idle_server_list, force_suspend);
244 /* as all clients are done, no need for them */
245 close_server_list(&pool->tested_server_list, "close unsafe file descriptors on suspend");
246 close_server_list(&pool->used_server_list, "close unsafe file descriptors on suspend");
253 * this function is called for each event loop.
255 void per_loop_maint(void)
260 int partial_pause = 0;
261 bool force_suspend = false;
263 if (cf_pause_mode == P_SUSPEND && cf_suspend_timeout > 0) {
264 usec_t stime = get_cached_time() - g_suspend_start;
265 if (stime >= cf_suspend_timeout)
266 force_suspend = true;
269 statlist_for_each(item, &pool_list) {
270 pool = container_of(item, PgPool, head);
273 switch (cf_pause_mode) {
275 if (pool->db->db_paused) {
277 active += per_loop_pause(pool);
279 per_loop_activate(pool);
282 active += per_loop_pause(pool);
285 active += per_loop_suspend(pool, force_suspend);
290 switch (cf_pause_mode) {
293 close_client_list(&login_client_list, "suspend_timeout");
295 active += statlist_count(&login_client_list);
301 if (partial_pause && !active)
307 /* maintaining clients in pool */
308 static void pool_client_maint(PgPool *pool)
311 usec_t now = get_cached_time();
315 /* force client_idle_timeout */
316 if (cf_client_idle_timeout > 0) {
317 statlist_for_each_safe(item, &pool->active_client_list, tmp) {
318 client = container_of(item, PgSocket, head);
319 Assert(client->state == CL_ACTIVE);
322 if (now - client->request_time > cf_client_idle_timeout)
323 disconnect_client(client, true, "client_idle_timeout");
327 /* force timeouts for waiting queries */
328 if (cf_query_timeout > 0 || cf_query_wait_timeout > 0) {
329 statlist_for_each_safe(item, &pool->waiting_client_list, tmp) {
330 client = container_of(item, PgSocket, head);
331 Assert(client->state == CL_WAITING);
332 if (client->query_start == 0) {
333 age = now - client->request_time;
334 //log_warning("query_start==0");
336 age = now - client->query_start;
338 if (cf_query_timeout > 0 && age > cf_query_timeout)
339 disconnect_client(client, true, "query_timeout");
340 else if (cf_query_wait_timeout > 0 && age > cf_query_wait_timeout)
341 disconnect_client(client, true, "query_wait_timeout");
345 /* apply client_login_timeout to clients waiting for welcome pkt */
346 if (cf_client_login_timeout > 0 && !pool->welcome_msg_ready) {
347 statlist_for_each_safe(item, &pool->waiting_client_list, tmp) {
348 client = container_of(item, PgSocket, head);
349 age = now - client->connect_time;
350 if (age > cf_client_login_timeout)
351 disconnect_client(client, true, "client_login_timeout (server down)");
356 static void check_unused_servers(PgPool *pool, StatList *slist, bool idle_test)
358 usec_t now = get_cached_time();
362 usec_t lifetime_kill_gap = 0;
365 * Calculate the time that disconnects because of server_lifetime
366 * must be separated. This avoids the need to re-launch lot
367 * of connections together.
369 if (pool->db->pool_size > 0)
370 lifetime_kill_gap = cf_server_lifetime / pool->db->pool_size;
372 /* disconnect idle servers if needed */
373 statlist_for_each_safe(item, slist, tmp) {
374 server = container_of(item, PgSocket, head);
376 age = now - server->connect_time;
377 idle = now - server->request_time;
379 if (server->close_needed) {
380 disconnect_server(server, true, "database configuration changed");
381 } else if (server->state == SV_IDLE && !server->ready) {
382 disconnect_server(server, true, "SV_IDLE server got dirty");
383 } else if (server->state == SV_USED && !server->ready) {
384 disconnect_server(server, true, "SV_USED server got dirty");
385 } else if (cf_server_idle_timeout > 0 && idle > cf_server_idle_timeout) {
386 disconnect_server(server, true, "server idle timeout");
387 } else if (age >= cf_server_lifetime) {
388 if (pool->last_lifetime_disconnect + lifetime_kill_gap <= now) {
389 disconnect_server(server, true, "server lifetime over");
390 pool->last_lifetime_disconnect = now;
392 } else if (cf_pause_mode == P_PAUSE) {
393 disconnect_server(server, true, "pause mode");
394 } else if (idle_test && *cf_server_check_query) {
395 if (idle > cf_server_check_delay)
396 change_server_state(server, SV_USED);
402 * Check pool size, close conns if too many. Makes pooler
403 * react faster to the case when admin decreased pool size.
405 static void check_pool_size(PgPool *pool)
408 int cur = statlist_count(&pool->active_server_list)
409 + statlist_count(&pool->idle_server_list)
410 + statlist_count(&pool->used_server_list)
411 + statlist_count(&pool->tested_server_list);
413 /* cancel pkt may create new srv conn without
414 * taking pool_size into account
416 * statlist_count(&pool->new_server_list)
419 int many = cur - (pool->db->pool_size + pool->db->res_pool_size);
421 Assert(pool->db->pool_size >= 0);
424 server = first_socket(&pool->used_server_list);
426 server = first_socket(&pool->idle_server_list);
429 disconnect_server(server, true, "too many servers in the pool");
434 * Because of fast-fail we may not have any waiting clients that would
435 * trigger server re-connect. So do it explicitly.
437 if (cur == 0 && pool->last_connect_failed)
438 launch_new_connection(pool);
441 /* maintain servers in a pool */
442 static void pool_server_maint(PgPool *pool)
445 usec_t age, now = get_cached_time();
448 /* find and disconnect idle servers */
449 check_unused_servers(pool, &pool->used_server_list, 0);
450 check_unused_servers(pool, &pool->tested_server_list, 0);
451 check_unused_servers(pool, &pool->idle_server_list, 1);
453 /* where query got did not get answer in query_timeout */
454 if (cf_query_timeout > 0) {
455 statlist_for_each_safe(item, &pool->active_server_list, tmp) {
456 server = container_of(item, PgSocket, head);
457 Assert(server->state == SV_ACTIVE);
460 age = now - server->link->request_time;
461 if (age > cf_query_timeout)
462 disconnect_server(server, true, "query timeout");
466 /* find connections that got connect, but could not log in */
467 if (cf_server_connect_timeout > 0) {
468 statlist_for_each_safe(item, &pool->new_server_list, tmp) {
469 server = container_of(item, PgSocket, head);
470 Assert(server->state == SV_LOGIN);
472 age = now - server->connect_time;
473 if (age > cf_server_connect_timeout)
474 disconnect_server(server, true, "connect timeout");
478 check_pool_size(pool);
481 static void cleanup_client_logins(void)
486 usec_t now = get_cached_time();
488 if (cf_client_login_timeout <= 0)
491 statlist_for_each_safe(item, &login_client_list, tmp) {
492 client = container_of(item, PgSocket, head);
493 age = now - client->connect_time;
494 if (age > cf_client_login_timeout)
495 disconnect_client(client, true, "client_login_timeout");
499 static void kill_database(PgDatabase *db);
500 static void cleanup_inactive_autodatabases(void)
505 usec_t now = get_cached_time();
507 if (cf_autodb_idle_timeout <= 0)
510 statlist_for_each_safe(item, &autodatabase_idle_list, tmp) {
511 db = container_of(item, PgDatabase, head);
512 age = now - db->inactive_time;
513 if (age > cf_autodb_idle_timeout)
520 /* full-scale maintenance, done only occasionally */
521 static void do_full_maint(int sock, short flags, void *arg)
527 * Avoid doing anything that may surprise other pgbouncer.
529 if (cf_pause_mode == P_SUSPEND)
532 statlist_for_each_safe(item, &pool_list, tmp) {
533 pool = container_of(item, PgPool, head);
536 pool_server_maint(pool);
537 pool_client_maint(pool);
538 if (pool->db->db_auto && pool->db->inactive_time == 0 &&
539 pool_client_count(pool) == 0 && pool_server_count(pool) == 0 ) {
540 pool->db->inactive_time = get_cached_time();
541 statlist_remove(&pool->db->head, &database_list);
542 statlist_append(&pool->db->head, &autodatabase_idle_list);
546 cleanup_inactive_autodatabases();
548 cleanup_client_logins();
550 if (cf_shutdown == 1 && get_active_server_count() == 0) {
551 log_info("server connections dropped, exiting");
557 if (cf_auth_type >= AUTH_TRUST)
558 loader_users_check();
561 safe_evtimer_add(&full_maint_ev, &full_maint_period);
564 /* first-time initializtion */
565 void janitor_setup(void)
567 /* launch maintenance */
568 evtimer_set(&full_maint_ev, do_full_maint, NULL);
569 safe_evtimer_add(&full_maint_ev, &full_maint_period);
572 static void kill_pool(PgPool *pool)
574 const char *reason = "database removed";
576 close_client_list(&pool->active_client_list, reason);
577 close_client_list(&pool->waiting_client_list, reason);
578 close_client_list(&pool->cancel_req_list, reason);
580 close_server_list(&pool->active_server_list, reason);
581 close_server_list(&pool->idle_server_list, reason);
582 close_server_list(&pool->used_server_list, reason);
583 close_server_list(&pool->tested_server_list, reason);
584 close_server_list(&pool->new_server_list, reason);
586 list_del(&pool->map_head);
587 statlist_remove(&pool->head, &pool_list);
588 obj_free(pool_cache, pool);
591 static void kill_database(PgDatabase *db)
596 log_warning("dropping database '%s' as it does not exist anymore or inactive auto-database", db->name);
598 statlist_for_each_safe(item, &pool_list, tmp) {
599 pool = container_of(item, PgPool, head);
604 obj_free(user_cache, db->forced_user);
605 if (db->connect_query)
606 free((void *)db->connect_query);
607 if (db->inactive_time)
608 statlist_remove(&db->head, &autodatabase_idle_list);
610 statlist_remove(&db->head, &database_list);
611 obj_free(db_cache, db);
614 /* as [pgbouncer] section can be loaded after databases,
615 there's need for review */
616 void config_postprocess(void)
621 statlist_for_each_safe(item, &database_list, tmp) {
622 db = container_of(item, PgDatabase, head);
627 if (db->pool_size < 0)
628 db->pool_size = cf_default_pool_size;
629 if (db->res_pool_size < 0)
630 db->res_pool_size = cf_res_pool_size;