Mercurial > hg > nginx
view src/http/ngx_http_copy_filter_module.c @ 6250:0256738454dc
Increased the default number of output buffers.
Since an output buffer can only be used for either reading or sending, small
amounts of data left from the previous operation (due to some limits) must be
sent before nginx will be able to read further into the buffer. Using only
one output buffer can result in suboptimal behavior that manifests itself in
forming and sending too small chunks of data. This is particularly painful
with SPDY (or HTTP/2) where each such chunk needs to be prefixed with some
header.
The default flow-control window in HTTP/2 is 64k minus one bytes. With one
32k output buffer this results is one byte left after exhausting the window.
With two 32k buffers the data will be read into the second free buffer before
sending, thus the minimum output is increased to 32k + 1 bytes which is much
better.
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Tue, 15 Sep 2015 17:49:15 +0300 |
parents | 1fdba317ee6d |
children | c5f81dcf97a7 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_bufs_t bufs; } ngx_http_copy_filter_conf_t; #if (NGX_HAVE_FILE_AIO) static void ngx_http_copy_aio_handler(ngx_output_chain_ctx_t *ctx, ngx_file_t *file); static void ngx_http_copy_aio_event_handler(ngx_event_t *ev); #if (NGX_HAVE_AIO_SENDFILE) static ssize_t ngx_http_copy_aio_sendfile_preload(ngx_buf_t *file); static void ngx_http_copy_aio_sendfile_event_handler(ngx_event_t *ev); #endif #endif #if (NGX_THREADS) static ngx_int_t ngx_http_copy_thread_handler(ngx_thread_task_t *task, ngx_file_t *file); static void ngx_http_copy_thread_event_handler(ngx_event_t *ev); #endif static void *ngx_http_copy_filter_create_conf(ngx_conf_t *cf); static char *ngx_http_copy_filter_merge_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_int_t ngx_http_copy_filter_init(ngx_conf_t *cf); static ngx_command_t ngx_http_copy_filter_commands[] = { { ngx_string("output_buffers"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE2, ngx_conf_set_bufs_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_copy_filter_conf_t, bufs), NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_copy_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_copy_filter_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_copy_filter_create_conf, /* create location configuration */ ngx_http_copy_filter_merge_conf /* merge location configuration */ }; ngx_module_t ngx_http_copy_filter_module = { NGX_MODULE_V1, &ngx_http_copy_filter_module_ctx, /* module context */ ngx_http_copy_filter_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_http_output_body_filter_pt ngx_http_next_body_filter; static ngx_int_t ngx_http_copy_filter(ngx_http_request_t *r, ngx_chain_t *in) { ngx_int_t rc; ngx_connection_t *c; ngx_output_chain_ctx_t *ctx; ngx_http_core_loc_conf_t *clcf; ngx_http_copy_filter_conf_t *conf; c = r->connection; ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "http copy filter: \"%V?%V\"", &r->uri, &r->args); ctx = ngx_http_get_module_ctx(r, ngx_http_copy_filter_module); if (ctx == NULL) { ctx = ngx_pcalloc(r->pool, sizeof(ngx_output_chain_ctx_t)); if (ctx == NULL) { return NGX_ERROR; } ngx_http_set_ctx(r, ctx, ngx_http_copy_filter_module); conf = ngx_http_get_module_loc_conf(r, ngx_http_copy_filter_module); clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); ctx->sendfile = c->sendfile; ctx->need_in_memory = r->main_filter_need_in_memory || r->filter_need_in_memory; ctx->need_in_temp = r->filter_need_temporary; ctx->alignment = clcf->directio_alignment; ctx->pool = r->pool; ctx->bufs = conf->bufs; ctx->tag = (ngx_buf_tag_t) &ngx_http_copy_filter_module; ctx->output_filter = (ngx_output_chain_filter_pt) ngx_http_next_body_filter; ctx->filter_ctx = r; #if (NGX_HAVE_FILE_AIO) if (ngx_file_aio && clcf->aio == NGX_HTTP_AIO_ON) { ctx->aio_handler = ngx_http_copy_aio_handler; #if (NGX_HAVE_AIO_SENDFILE) ctx->aio_preload = ngx_http_copy_aio_sendfile_preload; #endif } #endif #if (NGX_THREADS) if (clcf->aio == NGX_HTTP_AIO_THREADS) { ctx->thread_handler = ngx_http_copy_thread_handler; } #endif if (in && in->buf && ngx_buf_size(in->buf)) { r->request_output = 1; } } #if (NGX_HAVE_FILE_AIO || NGX_THREADS) ctx->aio = r->aio; #endif rc = ngx_output_chain(ctx, in); if (ctx->in == NULL) { r->buffered &= ~NGX_HTTP_COPY_BUFFERED; } else { r->buffered |= NGX_HTTP_COPY_BUFFERED; } ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0, "http copy filter: %i \"%V?%V\"", rc, &r->uri, &r->args); return rc; } #if (NGX_HAVE_FILE_AIO) static void ngx_http_copy_aio_handler(ngx_output_chain_ctx_t *ctx, ngx_file_t *file) { ngx_http_request_t *r; r = ctx->filter_ctx; file->aio->data = r; file->aio->handler = ngx_http_copy_aio_event_handler; r->main->blocked++; r->aio = 1; ctx->aio = 1; } static void ngx_http_copy_aio_event_handler(ngx_event_t *ev) { ngx_event_aio_t *aio; ngx_http_request_t *r; aio = ev->data; r = aio->data; r->main->blocked--; r->aio = 0; r->connection->write->handler(r->connection->write); } #if (NGX_HAVE_AIO_SENDFILE) static ssize_t ngx_http_copy_aio_sendfile_preload(ngx_buf_t *file) { ssize_t n; static u_char buf[1]; ngx_event_aio_t *aio; ngx_http_request_t *r; n = ngx_file_aio_read(file->file, buf, 1, file->file_pos, NULL); if (n == NGX_AGAIN) { aio = file->file->aio; aio->handler = ngx_http_copy_aio_sendfile_event_handler; r = aio->data; r->main->blocked++; r->aio = 1; } return n; } static void ngx_http_copy_aio_sendfile_event_handler(ngx_event_t *ev) { ngx_event_aio_t *aio; ngx_http_request_t *r; aio = ev->data; r = aio->data; r->main->blocked--; r->aio = 0; ev->complete = 0; r->connection->write->handler(r->connection->write); } #endif #endif #if (NGX_THREADS) static ngx_int_t ngx_http_copy_thread_handler(ngx_thread_task_t *task, ngx_file_t *file) { ngx_str_t name; ngx_thread_pool_t *tp; ngx_http_request_t *r; ngx_http_core_loc_conf_t *clcf; r = file->thread_ctx; clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); tp = clcf->thread_pool; if (tp == NULL) { if (ngx_http_complex_value(r, clcf->thread_pool_value, &name) != NGX_OK) { return NGX_ERROR; } tp = ngx_thread_pool_get((ngx_cycle_t *) ngx_cycle, &name); if (tp == NULL) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "thread pool \"%V\" not found", &name); return NGX_ERROR; } } task->event.data = r; task->event.handler = ngx_http_copy_thread_event_handler; if (ngx_thread_task_post(tp, task) != NGX_OK) { return NGX_ERROR; } r->main->blocked++; r->aio = 1; return NGX_OK; } static void ngx_http_copy_thread_event_handler(ngx_event_t *ev) { ngx_http_request_t *r; r = ev->data; r->main->blocked--; r->aio = 0; r->connection->write->handler(r->connection->write); } #endif static void * ngx_http_copy_filter_create_conf(ngx_conf_t *cf) { ngx_http_copy_filter_conf_t *conf; conf = ngx_palloc(cf->pool, sizeof(ngx_http_copy_filter_conf_t)); if (conf == NULL) { return NULL; } conf->bufs.num = 0; return conf; } static char * ngx_http_copy_filter_merge_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_copy_filter_conf_t *prev = parent; ngx_http_copy_filter_conf_t *conf = child; ngx_conf_merge_bufs_value(conf->bufs, prev->bufs, 2, 32768); return NULL; } static ngx_int_t ngx_http_copy_filter_init(ngx_conf_t *cf) { ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_copy_filter; return NGX_OK; }