Garbage collection in a storage system

摘要

A system and method for performing garbage collection. A system includes a storage medium, a first table including entries which map a virtual address to locations in the storage medium, and a second table with entries which include a reverse mapping of a physical address in a data storage medium to one or more virtual addresses. A storage controller is configured to perform garbage collection. During garbage collection, the controller is configured to identify one or more entries in the second table which correspond to a segment to be garbage collected. In response to determining the first table includes a valid mapping for a virtual address included in an entry of the one of the one or more entries, the controller is configured to copy data from a first location identified in the entry to a second location in the data storage medium, and reclaim the first storage location.

主权项

1. A computing system comprising:
a data storage medium; a first table comprising a plurality of entries, each of which includes a mapping of a virtual address to a physical location in the data storage medium; a second table comprising a plurality of entries, each of which includes a reverse mapping of a physical address in the data storage medium to one or more virtual addresses; and a data storage controller configured to perform a garbage collection process, wherein as part of the garbage collection process, the data storage controller is configured to:
identify one or more entries in the second table;in response to determining the first table includes a valid mapping for a virtual address included in an entry of the one of the one or more entries:
copy data from a first location identified in the entry to a second location in the data storage medium; andreclaim the first storage location.