| 摘要 |
A method for retrieving a logical block, including receiving a request to read the logical block, and obtaining metadata associated with the logical block, wherein the metadata includes a replication type used to store the logical block and physical block locations in a storage pool for each physical block associated with the logical block. The method further includes obtaining power state information including a power state for the storage devices specified in the physical block locations, selecting a first set of physical block locations using the metadata, the power state information, and a power-usage selection policy, and generating I/O requests, where each I/O request specifies one of the first set of physical block locations. The method further includes issuing the I/O requests, receiving physical blocks in response to the I/O requests, and constructing the logical block using the physical blocks. |
