Ok thanks. when I do TOP things looks normal to me.
I havent made any changes to httpd.conf but today apache died by itself and I see following in the logs.
Jun 26 09:30:03 2015] [crit] (22)Invalid argument: ap_queue_pop failed
[Fri Jun 26 09:30:03 2015] [crit] (22)Invalid argument: ap_queue_pop failed
[Fri Jun 26 09:30:03 2015] [crit] (22)Invalid argument: ap_queue_pop failed
[Fri Jun 26 09:30:03 2015] [crit] (22)Invalid argument: ap_queue_pop failed
[Fri Jun 26 09:30:03 2015] [emerg] (28)No space left on device: apr_proc_mutex_lock failed. Attempting to shutdown process gracefully.
[Fri Jun 26 09:30:04 2015] [emerg] (28)No space left on device: apr_proc_mutex_lock failed. Attempting to shutdown process gracefully.
[Fri Jun 26 09:30:06 2015] [emerg] (28)No space left on device: apr_proc_mutex_lock failed. Attempting to shutdown process gracefully.
[Fri Jun 26 09:31:28 2015] [alert] (11)Resource temporarily unavailable: apr_thread_create: unable to create worker thread
[Fri Jun 26 09:31:39 2015] [alert] Child 17330 returned a Fatal error...\nApache is exiting!
[Fri Jun 26 09:31:39 2015] [warn] child process 17173 still did not exit, sending a SIGTERM
[Fri Jun 26 09:31:39 2015] [warn] child process 17054 still did not exit, sending a SIGTERM
[Fri Jun 26 09:31:39 2015] [warn] child process 17310 still did not exit, sending a SIGTERM
[Fri Jun 26 09:31:39 2015] [warn] child process 17328 still did not exit, sending a SIGTERM
[Fri Jun 26 10:04:46 2015] [warn] pid file //prdbvn_ws/apache/logs/httpd.pid overwritten -- Unclean shutdown of previous Apache run?
[Fri Jun 26 10:04:47 2015] [notice] Apache configured -- resuming normal operations
I have to start it again.