MANAGING CACHE DATA AND METADATA

摘要

Techniques are provided for managing cache metadata that maps addresses on a storage medium (e.g., disk) to corresponding addresses on a cache device. Cache metadata may be stored in a hierarchical data structure. Only a subset of the levels of the hierarchy may be loaded to memory, thus reducing the cache metadata's memory "footprint" and expediting its restoration during startup. Startup may be further expedited by using cache metadata to perform operations associated with reboot. As requests to read data from storage are processed using cache metadata to identify the address(es) at which the data are stored in cache, the identified addressed may be stored in memory. When the computer is later shut down, instead of having to transfer the entirety of cache metadata from memory to storage, only the subset of the hierarchy levels and/or identified addresses may be transferred (e.g., to the cache device), expediting shutdown.