Two methods are available for zero data page reclaim: 1) using the Write Same or Unmap command from the host, and 2) using a REST API, CLI, or VSP One SDS Block Administrator. In both cases, pages are reclaimed when the storage controller receives the commands.
For zero data page reclaim by using a REST API, CLI, or VSP One SDS Block Administrator, the execution status can be referenced from volume information.
Zero data page reclaim can be performed when the applicable volume meets all of the following conditions.
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The status is "Normal", "Expanding", "Updating", or "DiscardZeroPageFailed."
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volumeType is "Normal" or "Snapshot."
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discardZeroDataPageStatus is "None" or "DiscardZeroDataPageFailed."
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Zero data page reclaim is processed one volume at a time within the same storage controller. In contrast, multiple jobs of zero data page reclaim are processed concurrently across different storage controllers.
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The maximum number of zero data page reclaim jobs that can be performed simultaneously is 800. Performing 801 or more zero data page reclaim jobs simultaneously results in failure.
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While zero data page reclaim is executed, the I/O performance of volume might be affected.
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When zero data page reclaim is being performed by using the Write Same command or Unmap command, if you perform zero data page reclaim for the same or other volumes simultaneously by using a REST API, CLI, or VSP One SDS Block Administrator, zero data page reclaim by using a REST API, CLI, or VSP One SDS Block Administrator is prioritized.
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If you perform a high-priority job (that cannot run with other jobs) such as storage cluster stoppage, zero data page reclaim is automatically stopped.
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For NVMe/TCP connections, pages are not reclaimed even if the storage controller receives the Dataset Management command from the host.
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Required role: VpsStorage