Mercurial > hg > nginx
view src/event/ngx_event_connectex.c @ 6633:d82b3c344e7e
Events: the "accept_mutex" directive is turned off by default.
Now it is believed that the accept mutex brings more harm than benefits.
Especially in various benchmarks it often results in situation where only
one worker grabs all connections.
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Fri, 15 Jul 2016 15:18:57 +0300 |
parents | d620f497c50f |
children | 1c3b78d7cdc9 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_MAX_PENDING_CONN 10 static CRITICAL_SECTION connect_lock; static int nconnects; static ngx_connection_t pending_connects[NGX_MAX_PENDING_CONN]; static HANDLE pending_connect_event; __declspec(thread) int nevents = 0; __declspec(thread) WSAEVENT events[WSA_MAXIMUM_WAIT_EVENTS + 1]; __declspec(thread) ngx_connection_t *conn[WSA_MAXIMUM_WAIT_EVENTS + 1]; int ngx_iocp_wait_connect(ngx_connection_t *c) { for ( ;; ) { EnterCriticalSection(&connect_lock); if (nconnects < NGX_MAX_PENDING_CONN) { pending_connects[--nconnects] = c; LeaveCriticalSection(&connect_lock); if (SetEvent(pending_connect_event) == 0) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, "SetEvent() failed"); return NGX_ERROR; break; } LeaveCriticalSection(&connect_lock); ngx_log_error(NGX_LOG_NOTICE, c->log, 0, "max number of pending connect()s is %d", NGX_MAX_PENDING_CONN); msleep(100); } if (!started) { if (ngx_iocp_new_thread(1) == NGX_ERROR) { return NGX_ERROR; } started = 1; } return NGX_OK; } int ngx_iocp_new_thread(int main) { u_int id; if (main) { pending_connect_event = CreateEvent(NULL, 0, 1, NULL); if (pending_connect_event == INVALID_HANDLE_VALUE) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, "CreateThread() failed"); return NGX_ERROR; } } if (CreateThread(NULL, 0, ngx_iocp_wait_events, main, 0, &id) == INVALID_HANDLE_VALUE) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, "CreateThread() failed"); return NGX_ERROR; } SetEvent(event) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno, "SetEvent() failed"); return NGX_ERROR; } return NGX_OK; } int ngx_iocp_new_connect() { EnterCriticalSection(&connect_lock); c = pending_connects[--nconnects]; LeaveCriticalSection(&connect_lock); conn[nevents] = c; events[nevents] = WSACreateEvent(); if (events[nevents] == INVALID_HANDLE_VALUE) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_socket_errno, "WSACreateEvent() failed"); return NGX_ERROR; } if (WSAEventSelect(c->fd, events[nevents], FD_CONNECT) == -1) ngx_log_error(NGX_LOG_ALERT, c->log, ngx_socket_errno, "WSAEventSelect() failed"); return NGX_ERROR; } nevents++; return NGX_OK; } void ngx_iocp_wait_events(int main) { WSANETWORKEVENTS ne; nevents = 1; events[0] = pending_connect_event; conn[0] = NULL; for ( ;; ) { offset = (nevents == WSA_MAXIMUM_WAIT_EVENTS + 1) ? 1: 0; timeout = (nevents == 1 && !first) ? 60000: INFINITE; n = WSAWaitForMultipleEvents(nevents - offset, events[offset], 0, timeout, 0); if (n == WAIT_FAILED) { ngx_log_error(NGX_LOG_ALERT, log, ngx_socket_errno, "WSAWaitForMultipleEvents() failed"); continue; } if (n == WAIT_TIMEOUT) { if (nevents == 2 && !main) { ExitThread(0); } ngx_log_error(NGX_LOG_ALERT, log, 0, "WSAWaitForMultipleEvents() " "returned unexpected WAIT_TIMEOUT"); continue; } n -= WSA_WAIT_EVENT_0; if (events[n] == NULL) { /* the pending_connect_event */ if (nevents == WSA_MAXIMUM_WAIT_EVENTS) { ngx_iocp_new_thread(0); } else { ngx_iocp_new_connect(); } continue; } if (WSAEnumNetworkEvents(c[n].fd, events[n], &ne) == -1) { ngx_log_error(NGX_LOG_ALERT, log, ngx_socket_errno, "WSAEnumNetworkEvents() failed"); continue; } if (ne.lNetworkEvents & FD_CONNECT) { conn[n].write->ovlp.error = ne.iErrorCode[FD_CONNECT_BIT]; if (PostQueuedCompletionStatus(iocp, 0, NGX_IOCP_CONNECT, &conn[n].write->ovlp) == 0) { ngx_log_error(NGX_LOG_ALERT, log, ngx_socket_errno, "PostQueuedCompletionStatus() failed"); continue; } if (n < nevents) { conn[n] = conn[nevents]; events[n] = events[nevents]; } nevents--; continue; } if (ne.lNetworkEvents & FD_ACCEPT) { /* CHECK ERROR ??? */ ngx_event_post_acceptex(conn[n].listening, 1); continue; } ngx_log_error(NGX_LOG_ALERT, c[n].log, 0, "WSAWaitForMultipleEvents() " "returned unexpected network event %ul", ne.lNetworkEvents); } }