Mercurial > hg > nginx
view src/os/win32/ngx_process.c @ 7583:efd71d49bde0
Events: available bytes calculation via ioctl(FIONREAD).
This makes it possible to avoid looping for a long time while working
with a fast enough peer when data are added to the socket buffer faster
than we are able to read and process them (ticket #1431). This is
basically what we already do on FreeBSD with kqueue, where information
about the number of bytes in the socket buffer is returned by
the kevent() call.
With other event methods rev->available is now set to -1 when the socket
is ready for reading. Later in ngx_recv() and ngx_recv_chain(), if
full buffer is received, real number of bytes in the socket buffer is
retrieved using ioctl(FIONREAD). Reading more than this number of bytes
ensures that even with edge-triggered event methods the event will be
triggered again, so it is safe to stop processing of the socket and
switch to other connections.
Using ioctl(FIONREAD) only after reading a full buffer is an optimization.
With this approach we only call ioctl(FIONREAD) when there are at least
two recv()/readv() calls.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 17 Oct 2019 16:02:19 +0300 |
parents | 7640d6c213e1 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> int ngx_argc; char **ngx_argv; char **ngx_os_argv; ngx_int_t ngx_last_process; ngx_process_t ngx_processes[NGX_MAX_PROCESSES]; ngx_pid_t ngx_spawn_process(ngx_cycle_t *cycle, char *name, ngx_int_t respawn) { u_long rc, n, code; ngx_int_t s; ngx_pid_t pid; ngx_exec_ctx_t ctx; HANDLE events[2]; char file[MAX_PATH + 1]; if (respawn >= 0) { s = respawn; } else { for (s = 0; s < ngx_last_process; s++) { if (ngx_processes[s].handle == NULL) { break; } } if (s == NGX_MAX_PROCESSES) { ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "no more than %d processes can be spawned", NGX_MAX_PROCESSES); return NGX_INVALID_PID; } } n = GetModuleFileName(NULL, file, MAX_PATH); if (n == 0) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "GetModuleFileName() failed"); return NGX_INVALID_PID; } file[n] = '\0'; ngx_log_debug1(NGX_LOG_DEBUG_CORE, cycle->log, 0, "GetModuleFileName: \"%s\"", file); ctx.path = file; ctx.name = name; ctx.args = GetCommandLine(); ctx.argv = NULL; ctx.envp = NULL; pid = ngx_execute(cycle, &ctx); if (pid == NGX_INVALID_PID) { return pid; } ngx_memzero(&ngx_processes[s], sizeof(ngx_process_t)); ngx_processes[s].handle = ctx.child; ngx_processes[s].pid = pid; ngx_processes[s].name = name; ngx_sprintf(ngx_processes[s].term_event, "ngx_%s_term_%P%Z", name, pid); ngx_sprintf(ngx_processes[s].quit_event, "ngx_%s_quit_%P%Z", name, pid); ngx_sprintf(ngx_processes[s].reopen_event, "ngx_%s_reopen_%P%Z", name, pid); events[0] = ngx_master_process_event; events[1] = ctx.child; rc = WaitForMultipleObjects(2, events, 0, 5000); ngx_time_update(); ngx_log_debug1(NGX_LOG_DEBUG_CORE, cycle->log, 0, "WaitForMultipleObjects: %ul", rc); switch (rc) { case WAIT_OBJECT_0: ngx_processes[s].term = OpenEvent(EVENT_MODIFY_STATE, 0, (char *) ngx_processes[s].term_event); if (ngx_processes[s].term == NULL) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "OpenEvent(\"%s\") failed", ngx_processes[s].term_event); goto failed; } ngx_processes[s].quit = OpenEvent(EVENT_MODIFY_STATE, 0, (char *) ngx_processes[s].quit_event); if (ngx_processes[s].quit == NULL) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "OpenEvent(\"%s\") failed", ngx_processes[s].quit_event); goto failed; } ngx_processes[s].reopen = OpenEvent(EVENT_MODIFY_STATE, 0, (char *) ngx_processes[s].reopen_event); if (ngx_processes[s].reopen == NULL) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "OpenEvent(\"%s\") failed", ngx_processes[s].reopen_event); goto failed; } if (ResetEvent(ngx_master_process_event) == 0) { ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "ResetEvent(\"%s\") failed", ngx_master_process_event_name); goto failed; } break; case WAIT_OBJECT_0 + 1: if (GetExitCodeProcess(ctx.child, &code) == 0) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "GetExitCodeProcess(%P) failed", pid); } ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "%s process %P exited with code %Xl", name, pid, code); goto failed; case WAIT_TIMEOUT: ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "the event \"%s\" was not signaled for 5s", ngx_master_process_event_name); goto failed; case WAIT_FAILED: ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "WaitForSingleObject(\"%s\") failed", ngx_master_process_event_name); goto failed; } if (respawn >= 0) { return pid; } switch (respawn) { case NGX_PROCESS_RESPAWN: ngx_processes[s].just_spawn = 0; break; case NGX_PROCESS_JUST_RESPAWN: ngx_processes[s].just_spawn = 1; break; } if (s == ngx_last_process) { ngx_last_process++; } return pid; failed: if (ngx_processes[s].reopen) { ngx_close_handle(ngx_processes[s].reopen); } if (ngx_processes[s].quit) { ngx_close_handle(ngx_processes[s].quit); } if (ngx_processes[s].term) { ngx_close_handle(ngx_processes[s].term); } TerminateProcess(ngx_processes[s].handle, 2); if (ngx_processes[s].handle) { ngx_close_handle(ngx_processes[s].handle); ngx_processes[s].handle = NULL; } return NGX_INVALID_PID; } ngx_pid_t ngx_execute(ngx_cycle_t *cycle, ngx_exec_ctx_t *ctx) { STARTUPINFO si; PROCESS_INFORMATION pi; ngx_memzero(&si, sizeof(STARTUPINFO)); si.cb = sizeof(STARTUPINFO); ngx_memzero(&pi, sizeof(PROCESS_INFORMATION)); if (CreateProcess(ctx->path, ctx->args, NULL, NULL, 0, CREATE_NO_WINDOW, NULL, NULL, &si, &pi) == 0) { ngx_log_error(NGX_LOG_CRIT, cycle->log, ngx_errno, "CreateProcess(\"%s\") failed", ngx_argv[0]); return 0; } ctx->child = pi.hProcess; if (CloseHandle(pi.hThread) == 0) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "CloseHandle(pi.hThread) failed"); } ngx_log_error(NGX_LOG_NOTICE, cycle->log, 0, "start %s process %P", ctx->name, pi.dwProcessId); return pi.dwProcessId; }