Mercurial > hg > nginx
view src/http/modules/ngx_http_upstream_least_conn_module.c @ 5438:f817f9d1cded
Configure: call "make clean" for OpenSSL only if Makefile exists.
This change allows to build nginx against git checkout of OpenSSL.
Signed-off-by: Piotr Sikora <piotr@cloudflare.com>
author | Piotr Sikora <piotr@cloudflare.com> |
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date | Mon, 04 Nov 2013 17:00:25 -0800 |
parents | 1d68b502088c |
children | 575175ebf4b4 |
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/* * Copyright (C) Maxim Dounin * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_uint_t *conns; } ngx_http_upstream_least_conn_conf_t; typedef struct { /* the round robin data must be first */ ngx_http_upstream_rr_peer_data_t rrp; ngx_uint_t *conns; ngx_event_get_peer_pt get_rr_peer; ngx_event_free_peer_pt free_rr_peer; } ngx_http_upstream_lc_peer_data_t; static ngx_int_t ngx_http_upstream_init_least_conn_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us); static ngx_int_t ngx_http_upstream_get_least_conn_peer( ngx_peer_connection_t *pc, void *data); static void ngx_http_upstream_free_least_conn_peer(ngx_peer_connection_t *pc, void *data, ngx_uint_t state); static void *ngx_http_upstream_least_conn_create_conf(ngx_conf_t *cf); static char *ngx_http_upstream_least_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_http_upstream_least_conn_commands[] = { { ngx_string("least_conn"), NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS, ngx_http_upstream_least_conn, 0, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_upstream_least_conn_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_http_upstream_least_conn_create_conf, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_upstream_least_conn_module = { NGX_MODULE_V1, &ngx_http_upstream_least_conn_module_ctx, /* module context */ ngx_http_upstream_least_conn_commands, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_int_t ngx_http_upstream_init_least_conn(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us) { ngx_uint_t n; ngx_http_upstream_rr_peers_t *peers; ngx_http_upstream_least_conn_conf_t *lcf; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, cf->log, 0, "init least conn"); if (ngx_http_upstream_init_round_robin(cf, us) != NGX_OK) { return NGX_ERROR; } peers = us->peer.data; n = peers->number; if (peers->next) { n += peers->next->number; } lcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_least_conn_module); lcf->conns = ngx_pcalloc(cf->pool, sizeof(ngx_uint_t) * n); if (lcf->conns == NULL) { return NGX_ERROR; } us->peer.init = ngx_http_upstream_init_least_conn_peer; return NGX_OK; } static ngx_int_t ngx_http_upstream_init_least_conn_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us) { ngx_http_upstream_lc_peer_data_t *lcp; ngx_http_upstream_least_conn_conf_t *lcf; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "init least conn peer"); lcf = ngx_http_conf_upstream_srv_conf(us, ngx_http_upstream_least_conn_module); lcp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_lc_peer_data_t)); if (lcp == NULL) { return NGX_ERROR; } lcp->conns = lcf->conns; r->upstream->peer.data = &lcp->rrp; if (ngx_http_upstream_init_round_robin_peer(r, us) != NGX_OK) { return NGX_ERROR; } r->upstream->peer.get = ngx_http_upstream_get_least_conn_peer; r->upstream->peer.free = ngx_http_upstream_free_least_conn_peer; lcp->get_rr_peer = ngx_http_upstream_get_round_robin_peer; lcp->free_rr_peer = ngx_http_upstream_free_round_robin_peer; return NGX_OK; } static ngx_int_t ngx_http_upstream_get_least_conn_peer(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_lc_peer_data_t *lcp = data; time_t now; uintptr_t m; ngx_int_t rc, total; ngx_uint_t i, n, p, many; ngx_http_upstream_rr_peer_t *peer, *best; ngx_http_upstream_rr_peers_t *peers; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get least conn peer, try: %ui", pc->tries); if (lcp->rrp.peers->single) { return lcp->get_rr_peer(pc, &lcp->rrp); } pc->cached = 0; pc->connection = NULL; now = ngx_time(); peers = lcp->rrp.peers; best = NULL; total = 0; #if (NGX_SUPPRESS_WARN) many = 0; p = 0; #endif for (i = 0; i < peers->number; i++) { n = i / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t)); if (lcp->rrp.tried[n] & m) { continue; } peer = &peers->peer[i]; if (peer->down) { continue; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { continue; } /* * select peer with least number of connections; if there are * multiple peers with the same number of connections, select * based on round-robin */ if (best == NULL || lcp->conns[i] * best->weight < lcp->conns[p] * peer->weight) { best = peer; many = 0; p = i; } else if (lcp->conns[i] * best->weight == lcp->conns[p] * peer->weight) { many = 1; } } if (best == NULL) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get least conn peer, no peer found"); goto failed; } if (many) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get least conn peer, many"); for (i = p; i < peers->number; i++) { n = i / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t)); if (lcp->rrp.tried[n] & m) { continue; } peer = &peers->peer[i]; if (peer->down) { continue; } if (lcp->conns[i] * best->weight != lcp->conns[p] * peer->weight) { continue; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { continue; } peer->current_weight += peer->effective_weight; total += peer->effective_weight; if (peer->effective_weight < peer->weight) { peer->effective_weight++; } if (peer->current_weight > best->current_weight) { best = peer; p = i; } } } best->current_weight -= total; if (now - best->checked > best->fail_timeout) { best->checked = now; } pc->sockaddr = best->sockaddr; pc->socklen = best->socklen; pc->name = &best->name; lcp->rrp.current = p; n = p / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t)); lcp->rrp.tried[n] |= m; lcp->conns[p]++; if (pc->tries == 1 && peers->next) { pc->tries += peers->next->number; } return NGX_OK; failed: if (peers->next) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get least conn peer, backup servers"); lcp->conns += peers->number; lcp->rrp.peers = peers->next; pc->tries = lcp->rrp.peers->number; n = (lcp->rrp.peers->number + (8 * sizeof(uintptr_t) - 1)) / (8 * sizeof(uintptr_t)); for (i = 0; i < n; i++) { lcp->rrp.tried[i] = 0; } rc = ngx_http_upstream_get_least_conn_peer(pc, lcp); if (rc != NGX_BUSY) { return rc; } } /* all peers failed, mark them as live for quick recovery */ for (i = 0; i < peers->number; i++) { peers->peer[i].fails = 0; } pc->name = peers->name; return NGX_BUSY; } static void ngx_http_upstream_free_least_conn_peer(ngx_peer_connection_t *pc, void *data, ngx_uint_t state) { ngx_http_upstream_lc_peer_data_t *lcp = data; ngx_log_debug2(NGX_LOG_DEBUG_HTTP, pc->log, 0, "free least conn peer %ui %ui", pc->tries, state); if (lcp->rrp.peers->single) { lcp->free_rr_peer(pc, &lcp->rrp, state); return; } lcp->conns[lcp->rrp.current]--; lcp->free_rr_peer(pc, &lcp->rrp, state); } static void * ngx_http_upstream_least_conn_create_conf(ngx_conf_t *cf) { ngx_http_upstream_least_conn_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_least_conn_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->conns = NULL; */ return conf; } static char * ngx_http_upstream_least_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_upstream_srv_conf_t *uscf; uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module); if (uscf->peer.init_upstream) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "load balancing method redefined"); } uscf->peer.init_upstream = ngx_http_upstream_init_least_conn; uscf->flags = NGX_HTTP_UPSTREAM_CREATE |NGX_HTTP_UPSTREAM_WEIGHT |NGX_HTTP_UPSTREAM_MAX_FAILS |NGX_HTTP_UPSTREAM_FAIL_TIMEOUT |NGX_HTTP_UPSTREAM_DOWN |NGX_HTTP_UPSTREAM_BACKUP; return NGX_CONF_OK; }