PID PPID %CPU VSZ WCHAN COMMAND 1867 1 0.0 14248 rt_sig nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf 22231 1867 0.2 18704 - nginx: worker process 22232 1867 0.2 27852 - nginx: worker process 32653 32619 0.0 1932 pipe_w egrep (nginx|PID) Thanks Igor. Posted at Nginx Forum: http://forum.nginx.org/read.php?2,191227,191456#msg-191456