How can I tell which program is causing high iowait on Redhat?

Discussion in 'Linux Discussion' started by joe, May 16, 2008.

  1. joe Guest

    I have a Redhat enterprise 3 box that has to be rebooted sometimes several times a week because of crippling iowait (between 80% - 95%). This seems to occur randomly and suddenly, I'm running apache, mysql, mailserver. sometimes i go a month without problems, other times I'm rebooting every day, how do I track down the culprit program? top shows CPU usage is very low during iowait problem times.
  2. Similar Threads: tell program
    Forum Title Date
    Linux Discussion Unix/programming question? Jun 18, 2008
    Linux Discussion Are there any unix/linux programs that use an xsl file to convert xml and return May 27, 2008
    Linux Discussion Programming an OS [unix-like machine]? May 24, 2008
    Linux Discussion Unix shell programming question? May 4, 2008

  3. joe Guest

    Oh this is a tough one. My first guess is with the SQL or mail server. First, check the mail logs and see if you're getting mail bombed or something weird like that. Then check the DB transaction logs. Is there a lot of activity here? If neither of these turn up anything, try switching one of the services off for a day. See if you still get the problem. If you do, then turn that service back on and try another. If the problem goes away, then you've narrowed it down.

Share This Page