Mercurial > hg > nginx
view src/misc/ngx_google_perftools_module.c @ 9138:a90f79792b5d
QUIC: optimized ACK delay.
Previously ACK was not generated if max_ack_delay was not yet expired and the
number of unacknowledged ack-eliciting packets was less than two, as allowed by
RFC 9000 13.2.1-13.2.2. However this only makes sense to avoid sending ACK-only
packets, as explained by the RFC:
On the other hand, reducing the frequency of packets that carry only
acknowledgments reduces packet transmission and processing cost at both
endpoints.
Now ACK is delayed only if output frame queue is empty. Otherwise ACK is sent
immediately, which significantly improves QUIC performance with certain tests.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Thu, 27 Jul 2023 16:37:17 +0400 |
parents | a27e0c7e198c |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> /* * declare Profiler interface here because * <google/profiler.h> is C++ header file */ int ProfilerStart(u_char* fname); void ProfilerStop(void); void ProfilerRegisterThread(void); static void *ngx_google_perftools_create_conf(ngx_cycle_t *cycle); static ngx_int_t ngx_google_perftools_worker(ngx_cycle_t *cycle); typedef struct { ngx_str_t profiles; } ngx_google_perftools_conf_t; static ngx_command_t ngx_google_perftools_commands[] = { { ngx_string("google_perftools_profiles"), NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE1, ngx_conf_set_str_slot, 0, offsetof(ngx_google_perftools_conf_t, profiles), NULL }, ngx_null_command }; static ngx_core_module_t ngx_google_perftools_module_ctx = { ngx_string("google_perftools"), ngx_google_perftools_create_conf, NULL }; ngx_module_t ngx_google_perftools_module = { NGX_MODULE_V1, &ngx_google_perftools_module_ctx, /* module context */ ngx_google_perftools_commands, /* module directives */ NGX_CORE_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ ngx_google_perftools_worker, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static void * ngx_google_perftools_create_conf(ngx_cycle_t *cycle) { ngx_google_perftools_conf_t *gptcf; gptcf = ngx_pcalloc(cycle->pool, sizeof(ngx_google_perftools_conf_t)); if (gptcf == NULL) { return NULL; } /* * set by ngx_pcalloc() * * gptcf->profiles = { 0, NULL }; */ return gptcf; } static ngx_int_t ngx_google_perftools_worker(ngx_cycle_t *cycle) { u_char *profile; ngx_google_perftools_conf_t *gptcf; gptcf = (ngx_google_perftools_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_google_perftools_module); if (gptcf->profiles.len == 0) { return NGX_OK; } profile = ngx_alloc(gptcf->profiles.len + NGX_INT_T_LEN + 2, cycle->log); if (profile == NULL) { return NGX_OK; } if (getenv("CPUPROFILE")) { /* disable inherited Profiler enabled in master process */ ProfilerStop(); } ngx_sprintf(profile, "%V.%d%Z", &gptcf->profiles, ngx_pid); if (ProfilerStart(profile)) { /* start ITIMER_PROF timer */ ProfilerRegisterThread(); } else { ngx_log_error(NGX_LOG_CRIT, cycle->log, ngx_errno, "ProfilerStart(%s) failed", profile); } ngx_free(profile); return NGX_OK; } /* ProfilerStop() is called on Profiler destruction */