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How to prevent high disk I/O?

Discussion in 'General Discussion' started by thewebhosting, Jul 17, 2009.

  1. thewebhosting

    thewebhosting Well-Known Member

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    I found high disk I/O when i use iostat -xtc command.

    Can anyone let me know what steps I need to follow in order to prevent this high I/O?

    Thanks!
     
  2. serversignature

    serversignature Well-Known Member

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    can you post the output of the following command below during your system's peak workload period.

    iostat 5 3 > io.out
     
  3. eth00

    eth00 Well-Known Member
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    Well the disk IO is the transfer, so stop the transfer and disk io drops ;)

    You could try noatime

    Are you swapping? That can kill the disk (IO wise)

    The below are not to lower it but divert and hopefully speed the machine up:

    Busy SQL server? Move SQL to another drive

    Move home to another drive perhaps?

    You could go RAID

    Really a lot of things you can do to help out, mor then just this.
     
  4. chirpy

    chirpy Well-Known Member

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    In addition to John's suggestions, you should probably check that you don't have actual disk IO subsystem problems by checking the disks read stats:

    hdparm -tT /dev/sda

    Where /dev/sda is the disk to check (check each of them). I've certainly seen it where there have been BIOS or build issues (or just slow disks) causing excessive IOWAIT.
     
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