Computer Hardware

Let\\\'s get technical…

How do I know which program is causing high iowait on RedHat?

I have a RedHat Enterprise 3 box must be rebooted several times a week because of the paralysis iowait (between 80% – 95%). This seems to occur randomly and suddenly I'm running Apache MySQL, mail server. Sometimes I go a month without problems, other times I reset every day, how can I find the culprit program? Top Shows CPU utilization is very low during periods of iowait problem.

Oh, this is a difficult question. My first guess is with the SQL or mail server. First, check e-mail records and see if mail bombed or something weird like that. Then check the DB transaction log. Is there much activity here? If any of these turn up anything, try to change a service for a day. Let's see If the problem still appears. If it does, then the service again and try another. If the problem disappears, then you've reduced.

Tags: cpu, cpu iowait high, iowait, linux, linux cpu iowait, performance, tips

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