Sign up ×
Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

From time to time load on my server (centos 4)jumps to 15 or more. I need to discover what process causes this high load on server. It there any script which can handle this for me ? I think its caused by mysql so even to discover the sql query would be great help.

share|improve this question

2 Answers 2

High server load typically caused by disk I/O. There are some ways to identify which process is waiting for disk I/O:

  • iotop
  • top -b -i -n 10
  • atop and press D
  • htop -> F2 to add 2 columns IO_RBYTES and IO_WBYTES, then F6 to sort
  • ...

You should especially pay attention to the processes in D state (uninterruptible sleep):

watch "ps -eo pid,user,state,command | awk '\$3 == /D/ { print \$0 }'"
share|improve this answer

look for something with a long runtime.

then EXPLAIN to see if it's making full table scans, generating temp tables, etc.

Otherwise, you can use something like the free version of Jet ( )


share|improve this answer
Another tool to look at is Innotop ( a top clone for MySQL. Also check out the Percona Toolkit ( – slillibri Sep 29 '11 at 18:32

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.