多个Nginx主进程

Question

当我用命令运行我的nginx服务器时：

/usr/local/nginx/sbin/nginx -c /usr/local/nginx/conf/nginx.conf

我有两个主过程

root     11632  2.6  0.1  76164  1372 ?        Ss   01:30   0:06 nginx: master process /usr/local/nginx/sbin/nginx -c /usr/local/nginx/conf/nginx.conf
www      14515  3.0 24.0 319920 245060 ?       S    01:35   0:00 nginx: worker process
www      14516  3.0 24.0 319920 245060 ?       S    01:35   0:00 nginx: worker process
www      14517  3.0 24.0 319920 245232 ?       S    01:35   0:00 nginx: worker process
www      14518  0.0  6.5 319920 66544 ?        R    01:35   0:00 nginx: master process /usr/local/nginx/sbin/nginx -c /usr/local/nginx/conf/nginx.conf

我的nginx.conf的一部分：

user  www www;

worker_processes 4;
error_log  /data/logs/nginx_error.log  crit;
pid        /usr/local/nginx/logs/nginx.pid;

worker_rlimit_nofile 600000;

events
{
  use epoll;
  worker_connections 600000;
}

当worker_processes小于4时，ps aux | grep nginx | grep -v grep看起来很好。如果worker_process为4，则它将有两个主进程。