Monitoring performance

You can monitor system performance using Performance Monitor. For more information, see the Performance Guide.

You can monitor information about pools and DP-VOLs using Command Control Interface (CCI). For more information, see the Command Control Interface User and Reference Guide.

The following activities help you to monitor and control performance of DP-VOLs. Collecting monitor information and subsequent tuning may increase throughput and the operating rates.

• Collecting monitor information:

  Collecting the following monitor information helps you determine the pool load (including the access frequency, and the access load upon data drives) and DP-VOL load (including the access frequency). You can then use this monitor information to tune the appropriate allocation.

  • Access frequency of DP-VOL, read hit rates, and write hit rates (using Performance Monitor)
  • Usage rates of parity groups of pools (using Performance Monitor)
  • Pool usage (using Device Manager - Storage Navigator)
  • DP-VOL usage (using Device Manager - Storage Navigator)
  • Dynamic Tiering performance monitoring of pool storage
• Possible tuning actions (without Dynamic Tiering):

  The following techniques using ShadowImage or Tiered Storage Manager will move a DP-VOL:

  • The DP-VOL is copied using ShadowImage from a pool with an I/O bottleneck. For more information, see the ShadowImage User Guide.
  • When normal volumes exist in the same parity group as the pool-VOL, Tiered Storage Manager can be used to move the normal volume to another parity group that is not shared with a pool-VOL.
  • ShadowImage copies a DP-VOL with a high I/O load to a pool with a lower access level to adjust the pool load.