Recovery Rate Control

Configure the global minimum array rebuild rate for single or multiple drive failures

Use this feature to configure the global minimum array rebuild rate (speed) for single or multiple drive failures.

Recommendation: Do not set minimum rebuild rates lower than 1,000 KB/sec or greater than 200,000 KB/sec. Values higher than 200,000 KB/sec are not likely to provide faster overall rebuild time, but IO performance will be impacted. Values lower than 1,000 are not likely to show an increase in IO performance during rebuilds. A value of zero (0) is permitted, but this will halt rebuild activity, which increases the risk to stored data.

Single drive failures are serious but not as critical as multiple drive failures, since an array being rebuilt because of a single drive failure could sustain another drive failure and remain operational. Therefore, the minimum rebuild rate setting for single-drive failures should typically be lower than for multiple-drive failures.

Multiple-drive failures are critical conditions and need as much speed as possible allocated to the rebuild process. This helps minimize the exposure of another drive failing while the array is being rebuilt. For this reason, Hewlett Packard Enterprise recommends setting the minimum rebuild rate for multiple drive failures to the maximum value of 200,000 KB/sec.

Minimum rebuild rates may also be configured for selected individual nodes, from the Node Control tab. For the selected nodes only, this will override the global minimum rebuild rate that is set in the following steps. For more information, see the Configure Minimum Rebuild Rates Per Node topic.

To set the global minimum rebuild rates:

  1. Navigate to the Configure tab.
  2. Click RAID Settings in the list of features on the left side of the screen.
    Also see the Global Recovery Rate Control section.
  3. Enter minimum rebuild rates (KB/sec) for single drive failures in the Single drive failure reconstruction rate field and in the Single drive failure reblance rate field.
    The default setting is 50,000 KB/sec.
  4. Enter the minimum rebuild rate for multiple drive failures in the Multiple drive failures (all rates) field.
    The default setting is 80,000 KB/sec.
  5. To save the changes, click the Apply button.