Storage system
AssigneeHitachi, Ltd.
InventorsTakahiro Yamamoto, Akira Yamamoto, Masakuni Agetsuma, Yoshinori Ohira, Hiroto Ebara
Life of this patent
Estimating the term…
Abstract
This invention provides a storage system enabling it to properly rebuild a storage device involved in failure. In the storage system, a controller repairs data for which an access request has been issued, returns a reply to the source of the access request, and stores the repaired data. As regards data for which access is not requested, the controller executes rebuilding of storage regions corresponding to rebuild management units in priority-based order and changes priority for executing the rebuilding, based on access frequencies for a first period and access frequencies for a second period that is shorter than the first period.
Claims7
A storage system adapted to perform rebuilding, comprising multiple storage devices to store data and a controller to process data that is input to or output from the storage devices,
- wherein, when failure has occurred in one of the storage devices, the controller repairs data stored in a storage device in which the failure has occurred, based on data and redundant data stored in other multiple storage devices
- wherein:
- the controller repairs data for which an access request has been issued, returns a reply to the source of the access request, and stores the repaired data;
- as regards data for which access is not requested, the controller executes rebuilding of storage regions corresponding to rebuild management units in priority-based order;
- and
- the controller changes priority for executing the rebuilding, based on access frequencies for a first period and access frequencies for a second period that is shorter than the first period.
A data processing method for use in a storage device adapted to perform rebuilding, comprising multiple storage devices to store data and a controller to process data that is input to or output from the storage devices,
- wherein, when failure has occurred in one of the storage devices, the controller repairs data stored in a storage device in which the failure has occurred, based on data and redundant data stored in other multiple storage devices,
- wherein:
- the controller repairs data for which an access request has been issued, returns a reply to the source of the access request, and stores the repaired data;
- as regards data for which access is not requested, the controller executes rebuilding of storage regions corresponding to rebuild management units in priority-based order;
- and
- the controller changes priority for executing the rebuilding, based on access frequencies for a first period and access frequencies for a second period that is shorter than the first period.
Dependencies are inferred from the claim text.