view src/core/ngx_radix_tree.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 45a460f82aec
children 62be1c4edfba d620f497c50f
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/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_RADIX_TREE_H_INCLUDED_
#define _NGX_RADIX_TREE_H_INCLUDED_


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


#define NGX_RADIX_NO_VALUE   (uintptr_t) -1

typedef struct ngx_radix_node_s  ngx_radix_node_t;

struct ngx_radix_node_s {
    ngx_radix_node_t  *right;
    ngx_radix_node_t  *left;
    ngx_radix_node_t  *parent;
    uintptr_t          value;
};


typedef struct {
    ngx_radix_node_t  *root;
    ngx_pool_t        *pool;
    ngx_radix_node_t  *free;
    char              *start;
    size_t             size;
} ngx_radix_tree_t;


ngx_radix_tree_t *ngx_radix_tree_create(ngx_pool_t *pool,
    ngx_int_t preallocate);
ngx_int_t ngx_radix32tree_insert(ngx_radix_tree_t *tree,
    uint32_t key, uint32_t mask, uintptr_t value);
ngx_int_t ngx_radix32tree_delete(ngx_radix_tree_t *tree,
    uint32_t key, uint32_t mask);
uintptr_t ngx_radix32tree_find(ngx_radix_tree_t *tree, uint32_t key);


#endif /* _NGX_RADIX_TREE_H_INCLUDED_ */