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Hi there I am pretty newbie in servers, would appreciate your help. How do I set up an iostat logging? as my Disk IO spikes strange at some random time to very high levels. Thanks.

simple
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1 Answers1

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IOSTAT provides stats for individual block devices, and won't tell you which process is actually driving IO. However, it's useful for characterizing your I/O access patterns. You can generate a large log-file with this command:

iostat -x sda -c 2 -t > stats.log

This will monitor sda (-x sda) every 2 seconds (-c 2) with a timestamp (-t). The logfile is not pretty, but it'll get you there.

sysadmin1138
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  • "...which process is actually driving..." is there one which can tell me and I can log the history to find out? for seeing the pattern of io spikes I can see it in linode dashboard. But really need to find out the issue and eliminate it. thanks. – simple Jan 26 '11 at 21:34
  • @Simple For that, read this question: http://serverfault.com/questions/25032/linux-disk-io-load-breakdown-by-filesystem-path-and-or-process – sysadmin1138 Jan 26 '11 at 21:41