view src/event/ngx_event_pipe.h @ 4233:aae172db7ac8

Event pipe: reduced number of file buffers used. If possible we now just extend already present file buffer in p->out chain instead of keeping ngx_buf_t for each buffer we've flushed to disk. This saves about 120 bytes of memory per buffer flushed to disk, and resolves high CPU usage observed in edge cases (due to coalescing these buffers on send).
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 31 Oct 2011 09:54:55 +0000
parents b66712cde67d
children d620f497c50f
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_EVENT_PIPE_H_INCLUDED_
#define _NGX_EVENT_PIPE_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>


typedef struct ngx_event_pipe_s  ngx_event_pipe_t;

typedef ngx_int_t (*ngx_event_pipe_input_filter_pt)(ngx_event_pipe_t *p,
                                                    ngx_buf_t *buf);
typedef ngx_int_t (*ngx_event_pipe_output_filter_pt)(void *data,
                                                     ngx_chain_t *chain);


struct ngx_event_pipe_s {
    ngx_connection_t  *upstream;
    ngx_connection_t  *downstream;

    ngx_chain_t       *free_raw_bufs;
    ngx_chain_t       *in;
    ngx_chain_t      **last_in;

    ngx_chain_t       *out;
    ngx_chain_t       *free;
    ngx_chain_t       *busy;

    /*
     * the input filter i.e. that moves HTTP/1.1 chunks
     * from the raw bufs to an incoming chain
     */

    ngx_event_pipe_input_filter_pt    input_filter;
    void                             *input_ctx;

    ngx_event_pipe_output_filter_pt   output_filter;
    void                             *output_ctx;

    unsigned           read:1;
    unsigned           cacheable:1;
    unsigned           single_buf:1;
    unsigned           free_bufs:1;
    unsigned           upstream_done:1;
    unsigned           upstream_error:1;
    unsigned           upstream_eof:1;
    unsigned           upstream_blocked:1;
    unsigned           downstream_done:1;
    unsigned           downstream_error:1;
    unsigned           cyclic_temp_file:1;

    ngx_int_t          allocated;
    ngx_bufs_t         bufs;
    ngx_buf_tag_t      tag;

    ssize_t            busy_size;

    off_t              read_length;
    off_t              length;

    off_t              max_temp_file_size;
    ssize_t            temp_file_write_size;

    ngx_msec_t         read_timeout;
    ngx_msec_t         send_timeout;
    ssize_t            send_lowat;

    ngx_pool_t        *pool;
    ngx_log_t         *log;

    ngx_chain_t       *preread_bufs;
    size_t             preread_size;
    ngx_buf_t         *buf_to_file;

    ngx_temp_file_t   *temp_file;

    /* STUB */ int     num;
};


ngx_int_t ngx_event_pipe(ngx_event_pipe_t *p, ngx_int_t do_write);
ngx_int_t ngx_event_pipe_copy_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf);
ngx_int_t ngx_event_pipe_add_free_buf(ngx_event_pipe_t *p, ngx_buf_t *b);


#endif /* _NGX_EVENT_PIPE_H_INCLUDED_ */