我有几个nginx网络服务器作为反向代理。
我发现一些服务器（不是全部）的活动连接（包括阅读写和等待，从http_stub_status模块看到）从3000一直增长到5000、10000 ...... 10k ...... 50k，即使在深夜也不会减少。
同时，我从netstat得到了一个更可靠的数字

netstat -nap | grep 80 | grep EST  | wc -l
2743

keepalive_timeout是10秒
所有工作进程同时启动

5265 nginx: master process         6-19:18:55 May19

24498  \_ nginx: worker process         59:34 19:16

24499  \_ nginx: worker process         59:34 19:16

24500  \_ nginx: worker process         59:34 19:16

24501  \_ nginx: worker process         59:34 19:16

24502  \_ nginx: cache manager pr       59:34 19:16

我发现了一个类似的问题：
http://markmail.org/search/?q=Upload+module+%2B+PHP+causes+active+connections+to+continually#query:Upload%20module%20%2B%20PHP%20causes%20active%20connections%20to%20continually+page:1+mid:fdgyk6v32lnvaxul+state:results
但对我来说好像不一样
error.log中没有相关错误
该系统

cat /etc/issue
CentOS release 5.3 (Final)
Kernel \r on an \m

uname -a
Linux 2.6.18-128.el5xen #1 SMP Wed Jan 21 11:12:42 EST 2009 x86_64 x86_64 x86_64 GNU/Linux

nginx版本：

nginx -V
nginx version: Nginx/1.0.14
built by gcc 4.1.2 20080704 (Red Hat 4.1.2-44)
TLS SNI support disabled
configure arguments: --prefix=/home/web/nginx/ --user=nobody --group=nobody 
--with-    http_ssl_module --with-http_sub_module --with-http_dav_module 
--with-http_flv_module --    with-http_gzip_static_module 
--with-http_stub_status_module --http-proxy-temp-path=/home/web/nginx/data/proxy 
--http-fastcgi-temp-path=/home/web/nginx/data/fastcgi 
--http-client-body-temp-path=/home/web/nginx/data/client --with-pcre=../pcre-7.9 
--add-module=../ngx_http_upstream_keepalive-d7643c291ef0 
--add-module=../hmux/ --add-module=../nginx-sticky-module-1.0/ 
--with-google_perftools_module --add-module=../nginx_upstream_check_module-660183a

这些单元是：

1: for cookie sticky
nginx-sticky-module.googlecode.com
2: hmux module for resin
code.google.com/p/nginx-hmux-module/
3: upstream check module
github.com/yaoweibin/nginx_upstream_check_module
4: upstream keepalive
mdounin.ru/hg/ngx_http_upstream_keepalive/

所有补丁都应用于nginx源代码。

nginx配置文件：

user  nobody;
worker_processes  4;
worker_cpu_affinity 0001 0010 0100 1000;
google_perftools_profiles /home/web/nginx/tcmalloc/tc;

events {
    worker_connections 51200;
    use epoll;
    epoll_events 4096;
    multi_accept on;
    accept_mutex off;   }

http {
    include       mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] '
                  '$status $body_bytes_sent ';

    access_log  logs/access.log  main;

    sendfile        on;
    keepalive_timeout  10;

    server_tokens off;

    gzip  on;
    gzip_types  text/plain text/css application/x-javascript text/xml application/json application/xml application/xml+rss text/javascript;
    gzip_vary on;

    server_names_hash_max_size 4096;
    proxy_buffer_size   64k;
    proxy_buffers       8 64k;
    proxy_busy_buffers_size     64k;
    client_header_buffer_size 64k;
    large_client_header_buffers 4 64k;
    proxy_headers_hash_max_size 1024;
    proxy_headers_hash_bucket_size 128;
    client_max_body_size 25m;

upstream backend{
    check interval=5000 fall=3 rise=2 timeout=2000 default_down=false type=tcp;
    keepalive 1024;
    server server1:80;
    server server2:80;
 }
server {
    listen       80;
    server_name  xxx;

    location / {
         proxy_pass http://backend;
    }

    error_page   500 502 503 504  /50x.html;

    location = /50x.html {
        root   html;
    }
}  

}