Logical sector mapping in a flash storage array
AssigneePure Storage, Inc.
InventorsJohn Colgrove, John Hayes, Ethan Miller, Feng Wang
Life of this patent
Estimating the term…
Abstract
A system and method for efficiently performing user storage virtualization for data stored in a storage system including a plurality of solid-state storage devices. A data storage subsystem supports multiple mapping tables. Records within a mapping table are arranged in multiple levels. Each level stores pairs of a key value and a pointer value. The levels are sorted by time. New records are inserted in a created newest (youngest) level. No edits are performed in-place. All levels other than the youngest may be read only. The system may further include an overlay table which identifies those keys within the mapping table that are invalid.
Claims20
A computing system comprising:
- a data storage medium;
- a data storage controller coupled to the data storage medium, the controller configured to:
- identify a query value corresponding to a read request;
- select, in dependence upon the query value, from a plurality of levels within a mapping table, the youngest level associated with the query value;
- and
- search the selected youngest level for an entry that maps the query value to a value corresponding to a location within the data storage medium.
A method for use in a storage system, the method comprising:
- identifying a query value corresponding to a read request;
- selecting, in dependence upon the query value, from a plurality of levels within a mapping table, the youngest level associated with the query value;
- and
- searching the selected youngest level for an entry that maps the query value to a value corresponding to a location within the data storage medium.
A non-transitory computer readable storage medium storing program instruction executable by a processor to:
- identify a query value corresponding to a read request;
- select, in dependence upon the query value, from a plurality of levels within a mapping table, the youngest level associated with the query value;
- and
- search the selected youngest level for an entry that maps the query value to a value corresponding to a location within the data storage medium.
Dependencies are inferred from the claim text.