Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Performance Tuning Guide

Disk I/O Settings

ProcedureTo tune disk I/O performance for non SCSI disks

  1. Test the disk speed.

    Use this command:

    /sbin/hdparm -t /dev/hdX
  2. Enable direct memory access (DMA).

    Use this command:

    /sbin/hdparm -d1 /dev/hdX
  3. Check the speed again using the hdparm command.

    Given that DMA is not enabled by default, the transfer rate might have improved considerably. In order to do this at every reboot, add the /sbin/hdparm -d1 /dev/hdX line to /etc/conf.d/local.start, /etc/init.d/rc.local, or whatever the startup script is called.

    For information on SCSI disks, see: System Tuning for Linux Servers — SCSI.