Mercurial > hg > nginx
view src/http/ngx_http_upstream_round_robin.c @ 7011:5e05118678af
Fixed background requests with asynchronous operations.
If the main request was finalized while a background request performed an
asynchronous operation, the main request ended up in ngx_http_writer() and was
not finalized until a network event or a timeout. For example, cache
background update with aio enabled made nginx unable to process further client
requests or close the connection, keeping it open until client closes it.
Now regular finalization of the main request is not suspended because of an
asynchronous operation in another request.
If a background request was terminated while an asynchronous operation was in
progress, background request's write event handler was changed to
ngx_http_request_finalizer() and never called again.
Now, whenever a request is terminated while an asynchronous operation is in
progress, connection error flag is set to make further finalizations of any
request with this connection lead to termination.
These issues appeared in 1aeaae6e9446 (not yet released).
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 29 May 2017 23:33:38 +0300 |
parents | d1d0dd69a419 |
children | 696df3ac27ac |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #define ngx_http_upstream_tries(p) ((p)->number \ + ((p)->next ? (p)->next->number : 0)) static ngx_http_upstream_rr_peer_t *ngx_http_upstream_get_peer( ngx_http_upstream_rr_peer_data_t *rrp); #if (NGX_HTTP_SSL) static ngx_int_t ngx_http_upstream_empty_set_session(ngx_peer_connection_t *pc, void *data); static void ngx_http_upstream_empty_save_session(ngx_peer_connection_t *pc, void *data); #endif ngx_int_t ngx_http_upstream_init_round_robin(ngx_conf_t *cf, ngx_http_upstream_srv_conf_t *us) { ngx_url_t u; ngx_uint_t i, j, n, w; ngx_http_upstream_server_t *server; ngx_http_upstream_rr_peer_t *peer, **peerp; ngx_http_upstream_rr_peers_t *peers, *backup; us->peer.init = ngx_http_upstream_init_round_robin_peer; if (us->servers) { server = us->servers->elts; n = 0; w = 0; for (i = 0; i < us->servers->nelts; i++) { if (server[i].backup) { continue; } n += server[i].naddrs; w += server[i].naddrs * server[i].weight; } if (n == 0) { ngx_log_error(NGX_LOG_EMERG, cf->log, 0, "no servers in upstream \"%V\" in %s:%ui", &us->host, us->file_name, us->line); return NGX_ERROR; } peers = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peers_t)); if (peers == NULL) { return NGX_ERROR; } peer = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peer_t) * n); if (peer == NULL) { return NGX_ERROR; } peers->single = (n == 1); peers->number = n; peers->weighted = (w != n); peers->total_weight = w; peers->name = &us->host; n = 0; peerp = &peers->peer; for (i = 0; i < us->servers->nelts; i++) { if (server[i].backup) { continue; } for (j = 0; j < server[i].naddrs; j++) { peer[n].sockaddr = server[i].addrs[j].sockaddr; peer[n].socklen = server[i].addrs[j].socklen; peer[n].name = server[i].addrs[j].name; peer[n].weight = server[i].weight; peer[n].effective_weight = server[i].weight; peer[n].current_weight = 0; peer[n].max_conns = server[i].max_conns; peer[n].max_fails = server[i].max_fails; peer[n].fail_timeout = server[i].fail_timeout; peer[n].down = server[i].down; peer[n].server = server[i].name; *peerp = &peer[n]; peerp = &peer[n].next; n++; } } us->peer.data = peers; /* backup servers */ n = 0; w = 0; for (i = 0; i < us->servers->nelts; i++) { if (!server[i].backup) { continue; } n += server[i].naddrs; w += server[i].naddrs * server[i].weight; } if (n == 0) { return NGX_OK; } backup = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peers_t)); if (backup == NULL) { return NGX_ERROR; } peer = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peer_t) * n); if (peer == NULL) { return NGX_ERROR; } peers->single = 0; backup->single = 0; backup->number = n; backup->weighted = (w != n); backup->total_weight = w; backup->name = &us->host; n = 0; peerp = &backup->peer; for (i = 0; i < us->servers->nelts; i++) { if (!server[i].backup) { continue; } for (j = 0; j < server[i].naddrs; j++) { peer[n].sockaddr = server[i].addrs[j].sockaddr; peer[n].socklen = server[i].addrs[j].socklen; peer[n].name = server[i].addrs[j].name; peer[n].weight = server[i].weight; peer[n].effective_weight = server[i].weight; peer[n].current_weight = 0; peer[n].max_conns = server[i].max_conns; peer[n].max_fails = server[i].max_fails; peer[n].fail_timeout = server[i].fail_timeout; peer[n].down = server[i].down; peer[n].server = server[i].name; *peerp = &peer[n]; peerp = &peer[n].next; n++; } } peers->next = backup; return NGX_OK; } /* an upstream implicitly defined by proxy_pass, etc. */ if (us->port == 0) { ngx_log_error(NGX_LOG_EMERG, cf->log, 0, "no port in upstream \"%V\" in %s:%ui", &us->host, us->file_name, us->line); return NGX_ERROR; } ngx_memzero(&u, sizeof(ngx_url_t)); u.host = us->host; u.port = us->port; if (ngx_inet_resolve_host(cf->pool, &u) != NGX_OK) { if (u.err) { ngx_log_error(NGX_LOG_EMERG, cf->log, 0, "%s in upstream \"%V\" in %s:%ui", u.err, &us->host, us->file_name, us->line); } return NGX_ERROR; } n = u.naddrs; peers = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peers_t)); if (peers == NULL) { return NGX_ERROR; } peer = ngx_pcalloc(cf->pool, sizeof(ngx_http_upstream_rr_peer_t) * n); if (peer == NULL) { return NGX_ERROR; } peers->single = (n == 1); peers->number = n; peers->weighted = 0; peers->total_weight = n; peers->name = &us->host; peerp = &peers->peer; for (i = 0; i < u.naddrs; i++) { peer[i].sockaddr = u.addrs[i].sockaddr; peer[i].socklen = u.addrs[i].socklen; peer[i].name = u.addrs[i].name; peer[i].weight = 1; peer[i].effective_weight = 1; peer[i].current_weight = 0; peer[i].max_conns = 0; peer[i].max_fails = 1; peer[i].fail_timeout = 10; *peerp = &peer[i]; peerp = &peer[i].next; } us->peer.data = peers; /* implicitly defined upstream has no backup servers */ return NGX_OK; } ngx_int_t ngx_http_upstream_init_round_robin_peer(ngx_http_request_t *r, ngx_http_upstream_srv_conf_t *us) { ngx_uint_t n; ngx_http_upstream_rr_peer_data_t *rrp; rrp = r->upstream->peer.data; if (rrp == NULL) { rrp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_rr_peer_data_t)); if (rrp == NULL) { return NGX_ERROR; } r->upstream->peer.data = rrp; } rrp->peers = us->peer.data; rrp->current = NULL; rrp->config = 0; n = rrp->peers->number; if (rrp->peers->next && rrp->peers->next->number > n) { n = rrp->peers->next->number; } if (n <= 8 * sizeof(uintptr_t)) { rrp->tried = &rrp->data; rrp->data = 0; } else { n = (n + (8 * sizeof(uintptr_t) - 1)) / (8 * sizeof(uintptr_t)); rrp->tried = ngx_pcalloc(r->pool, n * sizeof(uintptr_t)); if (rrp->tried == NULL) { return NGX_ERROR; } } r->upstream->peer.get = ngx_http_upstream_get_round_robin_peer; r->upstream->peer.free = ngx_http_upstream_free_round_robin_peer; r->upstream->peer.tries = ngx_http_upstream_tries(rrp->peers); #if (NGX_HTTP_SSL) r->upstream->peer.set_session = ngx_http_upstream_set_round_robin_peer_session; r->upstream->peer.save_session = ngx_http_upstream_save_round_robin_peer_session; #endif return NGX_OK; } ngx_int_t ngx_http_upstream_create_round_robin_peer(ngx_http_request_t *r, ngx_http_upstream_resolved_t *ur) { u_char *p; size_t len; socklen_t socklen; ngx_uint_t i, n; struct sockaddr *sockaddr; ngx_http_upstream_rr_peer_t *peer, **peerp; ngx_http_upstream_rr_peers_t *peers; ngx_http_upstream_rr_peer_data_t *rrp; rrp = r->upstream->peer.data; if (rrp == NULL) { rrp = ngx_palloc(r->pool, sizeof(ngx_http_upstream_rr_peer_data_t)); if (rrp == NULL) { return NGX_ERROR; } r->upstream->peer.data = rrp; } peers = ngx_pcalloc(r->pool, sizeof(ngx_http_upstream_rr_peers_t)); if (peers == NULL) { return NGX_ERROR; } peer = ngx_pcalloc(r->pool, sizeof(ngx_http_upstream_rr_peer_t) * ur->naddrs); if (peer == NULL) { return NGX_ERROR; } peers->single = (ur->naddrs == 1); peers->number = ur->naddrs; peers->name = &ur->host; if (ur->sockaddr) { peer[0].sockaddr = ur->sockaddr; peer[0].socklen = ur->socklen; peer[0].name = ur->name.data ? ur->name : ur->host; peer[0].weight = 1; peer[0].effective_weight = 1; peer[0].current_weight = 0; peer[0].max_conns = 0; peer[0].max_fails = 1; peer[0].fail_timeout = 10; peers->peer = peer; } else { peerp = &peers->peer; for (i = 0; i < ur->naddrs; i++) { socklen = ur->addrs[i].socklen; sockaddr = ngx_palloc(r->pool, socklen); if (sockaddr == NULL) { return NGX_ERROR; } ngx_memcpy(sockaddr, ur->addrs[i].sockaddr, socklen); ngx_inet_set_port(sockaddr, ur->port); p = ngx_pnalloc(r->pool, NGX_SOCKADDR_STRLEN); if (p == NULL) { return NGX_ERROR; } len = ngx_sock_ntop(sockaddr, socklen, p, NGX_SOCKADDR_STRLEN, 1); peer[i].sockaddr = sockaddr; peer[i].socklen = socklen; peer[i].name.len = len; peer[i].name.data = p; peer[i].weight = 1; peer[i].effective_weight = 1; peer[i].current_weight = 0; peer[i].max_conns = 0; peer[i].max_fails = 1; peer[i].fail_timeout = 10; *peerp = &peer[i]; peerp = &peer[i].next; } } rrp->peers = peers; rrp->current = NULL; rrp->config = 0; if (rrp->peers->number <= 8 * sizeof(uintptr_t)) { rrp->tried = &rrp->data; rrp->data = 0; } else { n = (rrp->peers->number + (8 * sizeof(uintptr_t) - 1)) / (8 * sizeof(uintptr_t)); rrp->tried = ngx_pcalloc(r->pool, n * sizeof(uintptr_t)); if (rrp->tried == NULL) { return NGX_ERROR; } } r->upstream->peer.get = ngx_http_upstream_get_round_robin_peer; r->upstream->peer.free = ngx_http_upstream_free_round_robin_peer; r->upstream->peer.tries = ngx_http_upstream_tries(rrp->peers); #if (NGX_HTTP_SSL) r->upstream->peer.set_session = ngx_http_upstream_empty_set_session; r->upstream->peer.save_session = ngx_http_upstream_empty_save_session; #endif return NGX_OK; } ngx_int_t ngx_http_upstream_get_round_robin_peer(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_rr_peer_data_t *rrp = data; ngx_int_t rc; ngx_uint_t i, n; ngx_http_upstream_rr_peer_t *peer; ngx_http_upstream_rr_peers_t *peers; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get rr peer, try: %ui", pc->tries); pc->cached = 0; pc->connection = NULL; peers = rrp->peers; ngx_http_upstream_rr_peers_wlock(peers); if (peers->single) { peer = peers->peer; if (peer->down) { goto failed; } if (peer->max_conns && peer->conns >= peer->max_conns) { goto failed; } rrp->current = peer; } else { /* there are several peers */ peer = ngx_http_upstream_get_peer(rrp); if (peer == NULL) { goto failed; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, pc->log, 0, "get rr peer, current: %p %i", peer, peer->current_weight); } pc->sockaddr = peer->sockaddr; pc->socklen = peer->socklen; pc->name = &peer->name; peer->conns++; ngx_http_upstream_rr_peers_unlock(peers); return NGX_OK; failed: if (peers->next) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, pc->log, 0, "backup servers"); rrp->peers = peers->next; n = (rrp->peers->number + (8 * sizeof(uintptr_t) - 1)) / (8 * sizeof(uintptr_t)); for (i = 0; i < n; i++) { rrp->tried[i] = 0; } ngx_http_upstream_rr_peers_unlock(peers); rc = ngx_http_upstream_get_round_robin_peer(pc, rrp); if (rc != NGX_BUSY) { return rc; } ngx_http_upstream_rr_peers_wlock(peers); } ngx_http_upstream_rr_peers_unlock(peers); pc->name = peers->name; return NGX_BUSY; } static ngx_http_upstream_rr_peer_t * ngx_http_upstream_get_peer(ngx_http_upstream_rr_peer_data_t *rrp) { time_t now; uintptr_t m; ngx_int_t total; ngx_uint_t i, n, p; ngx_http_upstream_rr_peer_t *peer, *best; now = ngx_time(); best = NULL; total = 0; #if (NGX_SUPPRESS_WARN) p = 0; #endif for (peer = rrp->peers->peer, i = 0; peer; peer = peer->next, i++) { n = i / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << i % (8 * sizeof(uintptr_t)); if (rrp->tried[n] & m) { continue; } if (peer->down) { continue; } if (peer->max_fails && peer->fails >= peer->max_fails && now - peer->checked <= peer->fail_timeout) { continue; } if (peer->max_conns && peer->conns >= peer->max_conns) { continue; } peer->current_weight += peer->effective_weight; total += peer->effective_weight; if (peer->effective_weight < peer->weight) { peer->effective_weight++; } if (best == NULL || peer->current_weight > best->current_weight) { best = peer; p = i; } } if (best == NULL) { return NULL; } rrp->current = best; n = p / (8 * sizeof(uintptr_t)); m = (uintptr_t) 1 << p % (8 * sizeof(uintptr_t)); rrp->tried[n] |= m; best->current_weight -= total; if (now - best->checked > best->fail_timeout) { best->checked = now; } return best; } void ngx_http_upstream_free_round_robin_peer(ngx_peer_connection_t *pc, void *data, ngx_uint_t state) { ngx_http_upstream_rr_peer_data_t *rrp = data; time_t now; ngx_http_upstream_rr_peer_t *peer; ngx_log_debug2(NGX_LOG_DEBUG_HTTP, pc->log, 0, "free rr peer %ui %ui", pc->tries, state); /* TODO: NGX_PEER_KEEPALIVE */ peer = rrp->current; ngx_http_upstream_rr_peers_rlock(rrp->peers); ngx_http_upstream_rr_peer_lock(rrp->peers, peer); if (rrp->peers->single) { peer->conns--; ngx_http_upstream_rr_peer_unlock(rrp->peers, peer); ngx_http_upstream_rr_peers_unlock(rrp->peers); pc->tries = 0; return; } if (state & NGX_PEER_FAILED) { now = ngx_time(); peer->fails++; peer->accessed = now; peer->checked = now; if (peer->max_fails) { peer->effective_weight -= peer->weight / peer->max_fails; if (peer->fails >= peer->max_fails) { ngx_log_error(NGX_LOG_WARN, pc->log, 0, "upstream server temporarily disabled"); } } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, pc->log, 0, "free rr peer failed: %p %i", peer, peer->effective_weight); if (peer->effective_weight < 0) { peer->effective_weight = 0; } } else { /* mark peer live if check passed */ if (peer->accessed < peer->checked) { peer->fails = 0; } } peer->conns--; ngx_http_upstream_rr_peer_unlock(rrp->peers, peer); ngx_http_upstream_rr_peers_unlock(rrp->peers); if (pc->tries) { pc->tries--; } } #if (NGX_HTTP_SSL) ngx_int_t ngx_http_upstream_set_round_robin_peer_session(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_rr_peer_data_t *rrp = data; ngx_int_t rc; ngx_ssl_session_t *ssl_session; ngx_http_upstream_rr_peer_t *peer; #if (NGX_HTTP_UPSTREAM_ZONE) int len; #if OPENSSL_VERSION_NUMBER >= 0x0090707fL const #endif u_char *p; ngx_http_upstream_rr_peers_t *peers; u_char buf[NGX_SSL_MAX_SESSION_SIZE]; #endif peer = rrp->current; #if (NGX_HTTP_UPSTREAM_ZONE) peers = rrp->peers; if (peers->shpool) { ngx_http_upstream_rr_peers_rlock(peers); ngx_http_upstream_rr_peer_lock(peers, peer); if (peer->ssl_session == NULL) { ngx_http_upstream_rr_peer_unlock(peers, peer); ngx_http_upstream_rr_peers_unlock(peers); return NGX_OK; } len = peer->ssl_session_len; ngx_memcpy(buf, peer->ssl_session, len); ngx_http_upstream_rr_peer_unlock(peers, peer); ngx_http_upstream_rr_peers_unlock(peers); p = buf; ssl_session = d2i_SSL_SESSION(NULL, &p, len); rc = ngx_ssl_set_session(pc->connection, ssl_session); ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "set session: %p", ssl_session); ngx_ssl_free_session(ssl_session); return rc; } #endif ssl_session = peer->ssl_session; rc = ngx_ssl_set_session(pc->connection, ssl_session); ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "set session: %p", ssl_session); return rc; } void ngx_http_upstream_save_round_robin_peer_session(ngx_peer_connection_t *pc, void *data) { ngx_http_upstream_rr_peer_data_t *rrp = data; ngx_ssl_session_t *old_ssl_session, *ssl_session; ngx_http_upstream_rr_peer_t *peer; #if (NGX_HTTP_UPSTREAM_ZONE) int len; u_char *p; ngx_http_upstream_rr_peers_t *peers; u_char buf[NGX_SSL_MAX_SESSION_SIZE]; #endif #if (NGX_HTTP_UPSTREAM_ZONE) peers = rrp->peers; if (peers->shpool) { ssl_session = SSL_get0_session(pc->connection->ssl->connection); if (ssl_session == NULL) { return; } ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "save session: %p", ssl_session); len = i2d_SSL_SESSION(ssl_session, NULL); /* do not cache too big session */ if (len > NGX_SSL_MAX_SESSION_SIZE) { return; } p = buf; (void) i2d_SSL_SESSION(ssl_session, &p); peer = rrp->current; ngx_http_upstream_rr_peers_rlock(peers); ngx_http_upstream_rr_peer_lock(peers, peer); if (len > peer->ssl_session_len) { ngx_shmtx_lock(&peers->shpool->mutex); if (peer->ssl_session) { ngx_slab_free_locked(peers->shpool, peer->ssl_session); } peer->ssl_session = ngx_slab_alloc_locked(peers->shpool, len); ngx_shmtx_unlock(&peers->shpool->mutex); if (peer->ssl_session == NULL) { peer->ssl_session_len = 0; ngx_http_upstream_rr_peer_unlock(peers, peer); ngx_http_upstream_rr_peers_unlock(peers); return; } peer->ssl_session_len = len; } ngx_memcpy(peer->ssl_session, buf, len); ngx_http_upstream_rr_peer_unlock(peers, peer); ngx_http_upstream_rr_peers_unlock(peers); return; } #endif ssl_session = ngx_ssl_get_session(pc->connection); if (ssl_session == NULL) { return; } ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "save session: %p", ssl_session); peer = rrp->current; old_ssl_session = peer->ssl_session; peer->ssl_session = ssl_session; if (old_ssl_session) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0, "old session: %p", old_ssl_session); /* TODO: may block */ ngx_ssl_free_session(old_ssl_session); } } static ngx_int_t ngx_http_upstream_empty_set_session(ngx_peer_connection_t *pc, void *data) { return NGX_OK; } static void ngx_http_upstream_empty_save_session(ngx_peer_connection_t *pc, void *data) { return; } #endif