System and method for cache replacement using access-ordering lookahead approach

A non-transitory computer-readable storage medium having instructions stored therein, which when executed by a processor, cause the processor to perform operations for cache management of a storage system, the operations comprising:

• in response to a request for accessing a file stored in a storage system, identifying and retrieving a plurality of data objects associated with the file from a storage device of the storage system, wherein the data objects constitute at least a portion of the file;
• caching the plurality of data objects of the file in a cache memory of the storage system;
• determining an access sequence of the cached data objects within the file based on metadata of the file, wherein the access sequence represents a sequential order in time of accessing the cached data objects within the file, wherein the data objects are deduplicated data objects within the file, and wherein at least one of the data objects appears more than once within the file;
• in response to a request for cache space reclamation, identifying one or more of the cached data objects whose next access is a farthest in time from a data object currently being accessed amongst the cached data objects within the file based on the access sequence of the data objects;
• and
• evicting the identified one or more data objects from the cache memory whose next access is a farthest amongst the cached data objects within the file.

A data processing system, comprising:

• a storage device to store a plurality of files;
• a cache memory to cache a plurality of data objects of a file stored in the storage device, wherein the data objects constitute at least a portion of the file, and wherein at least one of the data objects occurs more than once within the file;
• an access predictor to determine an access sequence of the cached data objects within the file based on metadata of the file, wherein the access sequence represents a sequential order in time of accessing the cached data objects within the file, wherein the data objects are deduplicated data objects within the file, and wherein at least one of the data objects appears more than once within the file;
• and
• an access manager, in response to a request for cache space reclamation, to identify a cached data object whose next access is a farthest in time from a data object currently being accessed amongst the cached data objects within the file based on the access sequence of the data objects, and to evict the identified data object from the cache memory whose next access is a farthest amongst the cached data objects within the file.