Storage virtualization apparatus causing access request process to be delayed based on incomplete count and storage virtualization method

摘要

A storage virtualization apparatus includes: a first storing unit to store, with respect to each storage port, a process incomplete command count defined as number of commands not yet processed by the storage device having each storage port; a control unit to obtain process incomplete command counts accumulated by other storage virtualization apparatuses, and stores into a second storing unit a process incomplete command total count that is a total of the process incomplete command counts obtained from the other storage virtualization apparatuses and the first storing unit; and an access request responding unit to, when receiving an access request, obtain the process incomplete command total count about a storage port corresponding to the received access request, and to, when the obtained process incomplete command total count is larger than a prescribed number, cause completion timing of an access responding process to the access request to be delayed.

主权项

1. A storage virtualization apparatus that controls access to one or more storage devices with a second storage virtualization apparatus, the storage virtualization apparatus comprising:
a controller; a memory; a first interface; and a second interface, wherein the storage devices include a storage port connected to the storage virtualization apparatus via the first interface, the storage port being connected to the second storage virtualization apparatus via a first interface of the second storage virtualization apparatus, the controller executes processes comprising: storing in the memory, a process incomplete command count calculated from a number of received access requests and a number of completed access requests; obtaining, via the second interface, from the second storage virtualization apparatus connected to the storage port, a process incomplete command count with respect to the storage port calculated by the second storage virtualization apparatus; storing in the memory, a process incomplete command total count to be obtained based on the process incomplete command count obtained from the second storage virtualization apparatus and the process incomplete command count obtained from the memory; notifying, via the second interface, the second storage virtualization apparatus of the obtained process incomplete command total count so as to update a process incomplete command total count in the second storage virtualization apparatus; and causing, upon receiving an access request to any one of the storage devices, when the obtained process incomplete command total count with respect to the storage port corresponding to the received access request is larger than a prescribed number, completion timing of an access responding process to the access request to be delayed.