Mercurial > hg > nginx
view src/core/ngx_buf.h @ 5569:462ae7eedc68 stable-1.4
Fixed TCP_DEFER_ACCEPT handling (ticket #353).
Backed out 05a56ebb084a, as it turns out that kernel can return connections
without any delay if syncookies are used. This basically means we can't
assume anything about connections returned with deferred accept set.
To solve original problem the 05a56ebb084a tried to solve, i.e. to don't
wait longer than needed if a connection was accepted after deferred accept
timeout, this patch changes a timeout set with setsockopt(TCP_DEFER_ACCEPT)
to 1 second, unconditionally. This is believed to be enough for speed
improvements, and doesn't imply major changes to timeouts used.
Note that before 2.6.32 connections were dropped after a timeout. Though
it is believed that 1s is still appropriate for kernels before 2.6.32,
as previously tcp_synack_retries controlled the actual timeout and 1s results
in more than 1 minute actual timeout by default.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Tue, 28 Jan 2014 15:40:46 +0400 |
parents | d620f497c50f |
children | f9c83484d9ce |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_BUF_H_INCLUDED_ #define _NGX_BUF_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> typedef void * ngx_buf_tag_t; typedef struct ngx_buf_s ngx_buf_t; struct ngx_buf_s { u_char *pos; u_char *last; off_t file_pos; off_t file_last; u_char *start; /* start of buffer */ u_char *end; /* end of buffer */ ngx_buf_tag_t tag; ngx_file_t *file; ngx_buf_t *shadow; /* the buf's content could be changed */ unsigned temporary:1; /* * the buf's content is in a memory cache or in a read only memory * and must not be changed */ unsigned memory:1; /* the buf's content is mmap()ed and must not be changed */ unsigned mmap:1; unsigned recycled:1; unsigned in_file:1; unsigned flush:1; unsigned sync:1; unsigned last_buf:1; unsigned last_in_chain:1; unsigned last_shadow:1; unsigned temp_file:1; /* STUB */ int num; }; struct ngx_chain_s { ngx_buf_t *buf; ngx_chain_t *next; }; typedef struct { ngx_int_t num; size_t size; } ngx_bufs_t; typedef struct ngx_output_chain_ctx_s ngx_output_chain_ctx_t; typedef ngx_int_t (*ngx_output_chain_filter_pt)(void *ctx, ngx_chain_t *in); #if (NGX_HAVE_FILE_AIO) typedef void (*ngx_output_chain_aio_pt)(ngx_output_chain_ctx_t *ctx, ngx_file_t *file); #endif struct ngx_output_chain_ctx_s { ngx_buf_t *buf; ngx_chain_t *in; ngx_chain_t *free; ngx_chain_t *busy; unsigned sendfile:1; unsigned directio:1; #if (NGX_HAVE_ALIGNED_DIRECTIO) unsigned unaligned:1; #endif unsigned need_in_memory:1; unsigned need_in_temp:1; #if (NGX_HAVE_FILE_AIO) unsigned aio:1; ngx_output_chain_aio_pt aio_handler; #endif off_t alignment; ngx_pool_t *pool; ngx_int_t allocated; ngx_bufs_t bufs; ngx_buf_tag_t tag; ngx_output_chain_filter_pt output_filter; void *filter_ctx; }; typedef struct { ngx_chain_t *out; ngx_chain_t **last; ngx_connection_t *connection; ngx_pool_t *pool; off_t limit; } ngx_chain_writer_ctx_t; #define NGX_CHAIN_ERROR (ngx_chain_t *) NGX_ERROR #define ngx_buf_in_memory(b) (b->temporary || b->memory || b->mmap) #define ngx_buf_in_memory_only(b) (ngx_buf_in_memory(b) && !b->in_file) #define ngx_buf_special(b) \ ((b->flush || b->last_buf || b->sync) \ && !ngx_buf_in_memory(b) && !b->in_file) #define ngx_buf_sync_only(b) \ (b->sync \ && !ngx_buf_in_memory(b) && !b->in_file && !b->flush && !b->last_buf) #define ngx_buf_size(b) \ (ngx_buf_in_memory(b) ? (off_t) (b->last - b->pos): \ (b->file_last - b->file_pos)) ngx_buf_t *ngx_create_temp_buf(ngx_pool_t *pool, size_t size); ngx_chain_t *ngx_create_chain_of_bufs(ngx_pool_t *pool, ngx_bufs_t *bufs); #define ngx_alloc_buf(pool) ngx_palloc(pool, sizeof(ngx_buf_t)) #define ngx_calloc_buf(pool) ngx_pcalloc(pool, sizeof(ngx_buf_t)) ngx_chain_t *ngx_alloc_chain_link(ngx_pool_t *pool); #define ngx_free_chain(pool, cl) \ cl->next = pool->chain; \ pool->chain = cl ngx_int_t ngx_output_chain(ngx_output_chain_ctx_t *ctx, ngx_chain_t *in); ngx_int_t ngx_chain_writer(void *ctx, ngx_chain_t *in); ngx_int_t ngx_chain_add_copy(ngx_pool_t *pool, ngx_chain_t **chain, ngx_chain_t *in); ngx_chain_t *ngx_chain_get_free_buf(ngx_pool_t *p, ngx_chain_t **free); void ngx_chain_update_chains(ngx_pool_t *p, ngx_chain_t **free, ngx_chain_t **busy, ngx_chain_t **out, ngx_buf_tag_t tag); #endif /* _NGX_BUF_H_INCLUDED_ */