view src/core/ngx_regex.h @ 4207:4fc91bae6f83

Better recheck of dead upstream servers. Previously nginx used to mark backend again as live as soon as fail_timeout passes (10s by default) since last failure. On the other hand, detecting dead backend takes up to 60s (proxy_connect_timeout) in typical situation "backend is down and doesn't respond to any packets". This resulted in suboptimal behaviour in the above situation (up to 23% of requests were directed to dead backend with default settings). More detailed description of the problem may be found here (in Russian): http://mailman.nginx.org/pipermail/nginx-ru/2011-August/042172.html Fix is to only allow one request after fail_timeout passes, and mark backend as "live" only if this request succeeds. Note that with new code backend will not be marked "live" unless "check" request is completed, and this may take a while in some specific workloads (e.g. streaming). This is believed to be acceptable.
author Maxim Dounin <mdounin@mdounin.ru>
date Wed, 12 Oct 2011 14:22:48 +0000
parents 42c16d8bddbe
children 005fc2d5e84f 4919fb357a5d
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/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_REGEX_H_INCLUDED_
#define _NGX_REGEX_H_INCLUDED_


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

#include <pcre.h>


#define NGX_REGEX_NO_MATCHED  PCRE_ERROR_NOMATCH   /* -1 */

#define NGX_REGEX_CASELESS    PCRE_CASELESS

typedef pcre  ngx_regex_t;


typedef struct {
    ngx_str_t     pattern;
    ngx_pool_t   *pool;
    ngx_int_t     options;

    ngx_regex_t  *regex;
    int           captures;
    int           named_captures;
    int           name_size;
    u_char       *names;
    ngx_str_t     err;
} ngx_regex_compile_t;


typedef struct {
    ngx_regex_t  *regex;
    u_char       *name;
} ngx_regex_elt_t;


void ngx_regex_init(void);
ngx_int_t ngx_regex_compile(ngx_regex_compile_t *rc);

#define ngx_regex_exec(re, s, captures, size)                                \
    pcre_exec(re, NULL, (const char *) (s)->data, (s)->len, 0, 0,            \
              captures, size)
#define ngx_regex_exec_n      "pcre_exec()"

ngx_int_t ngx_regex_exec_array(ngx_array_t *a, ngx_str_t *s, ngx_log_t *log);


#endif /* _NGX_REGEX_H_INCLUDED_ */