view src/core/ngx_inet.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 beaf94f2f265
children d620f497c50f
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_INET_H_INCLUDED_
#define _NGX_INET_H_INCLUDED_


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


/*
 * TODO: autoconfigure NGX_SOCKADDRLEN and NGX_SOCKADDR_STRLEN as
 *       sizeof(struct sockaddr_storage)
 *       sizeof(struct sockaddr_un)
 *       sizeof(struct sockaddr_in6)
 *       sizeof(struct sockaddr_in)
 */

#define NGX_INET_ADDRSTRLEN   (sizeof("255.255.255.255") - 1)
#define NGX_INET6_ADDRSTRLEN                                                 \
    (sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255") - 1)
#define NGX_UNIX_ADDRSTRLEN                                                  \
    (sizeof(struct sockaddr_un) - offsetof(struct sockaddr_un, sun_path))

#if (NGX_HAVE_UNIX_DOMAIN)
#define NGX_SOCKADDR_STRLEN   (sizeof("unix:") - 1 + NGX_UNIX_ADDRSTRLEN)
#else
#define NGX_SOCKADDR_STRLEN   (NGX_INET6_ADDRSTRLEN + sizeof(":65535") - 1)
#endif

#if (NGX_HAVE_UNIX_DOMAIN)
#define NGX_SOCKADDRLEN       sizeof(struct sockaddr_un)
#else
#define NGX_SOCKADDRLEN       512
#endif


typedef struct {
    in_addr_t                 addr;
    in_addr_t                 mask;
} ngx_in_cidr_t;


#if (NGX_HAVE_INET6)

typedef struct {
    struct in6_addr           addr;
    struct in6_addr           mask;
} ngx_in6_cidr_t;

#endif


typedef struct {
    ngx_uint_t                family;
    union {
        ngx_in_cidr_t         in;
#if (NGX_HAVE_INET6)
        ngx_in6_cidr_t        in6;
#endif
    } u;
} ngx_cidr_t;


typedef struct {
    struct sockaddr          *sockaddr;
    socklen_t                 socklen;
    ngx_str_t                 name;
} ngx_addr_t;


typedef struct {
    ngx_str_t                 url;
    ngx_str_t                 host;
    ngx_str_t                 port_text;
    ngx_str_t                 uri;

    in_port_t                 port;
    in_port_t                 default_port;
    int                       family;

    unsigned                  listen:1;
    unsigned                  uri_part:1;
    unsigned                  no_resolve:1;
    unsigned                  one_addr:1;

    unsigned                  no_port:1;
    unsigned                  wildcard:1;

    socklen_t                 socklen;
    u_char                    sockaddr[NGX_SOCKADDRLEN];

    ngx_addr_t               *addrs;
    ngx_uint_t                naddrs;

    char                     *err;
} ngx_url_t;


in_addr_t ngx_inet_addr(u_char *text, size_t len);
#if (NGX_HAVE_INET6)
ngx_int_t ngx_inet6_addr(u_char *p, size_t len, u_char *addr);
size_t ngx_inet6_ntop(u_char *p, u_char *text, size_t len);
#endif
size_t ngx_sock_ntop(struct sockaddr *sa, u_char *text, size_t len,
    ngx_uint_t port);
size_t ngx_inet_ntop(int family, void *addr, u_char *text, size_t len);
ngx_int_t ngx_ptocidr(ngx_str_t *text, ngx_cidr_t *cidr);
ngx_int_t ngx_parse_addr(ngx_pool_t *pool, ngx_addr_t *addr, u_char *text,
    size_t len);
ngx_int_t ngx_parse_url(ngx_pool_t *pool, ngx_url_t *u);
ngx_int_t ngx_inet_resolve_host(ngx_pool_t *pool, ngx_url_t *u);


#endif /* _NGX_INET_H_INCLUDED_ */