Abstract: A method for caching data in a storage system involves receiving a request for a first datum stored on a storage disk, retrieving the first datum from the storage disk when a copy of the first datum is not stored on an asymmetric cache device (ACD), storing a first copy of the first datum in a main memory, updating a list of data to include the first datum, storing, prior to any data being evicted from the main memory, a second copy of the first datum on the ACD, and evicting the first copy of the first datum from the main memory when a first copy of a second datum is designated for storing in the main memory and the main memory is full and the first datum is at the tail of the list of data.

Abstract: A system configured to receive a first request for a first datum, query the cache metadata to determine whether the first datum is present in the main memory or the asymmetric cache device (ACD), retrieve the first datum from the main memory when the first datum is present in the main memory, retrieve the first datum from the ACD when the first datum is present in the ACD and not present in the main memory, store a copy of the first datum in the main memory when the first datum is present in the ACD and not present in the main memory, update the cache metadata to indicate that the copy of the first datum is stored in the main memory when the first datum is present in the ACD and not present in the main memory, and retrieve the first datum from the disk when the first datum is not present in the ACD and is not present in the main memory.

Abstract: A method for caching data in a storage system involves receiving a request for a first datum stored on a storage disk, retrieving the first datum from the storage disk when a copy of the first datum is not stored in a main memory and when a copy of the first datum is not stored on an asymmetric cache device (ACD), storing a first copy of the first datum in the main memory, updating a list of data to include the first datum, where each datum in the list of data is a datum for which a copy is stored in the main memory, where the list of data is sorted using a scheme such that a datum at a head of the list of data is most favored by the scheme and a datum at a tail of the list of data is least favored by the scheme, storing, prior to any data being evicted from the main memory, a second copy of the first datum on the ACD, where the first datum is one of a first group of data selected using a head-first search of the list of data, and evicting the first copy of the first datum from the main memory when a first co

Abstract: A system configured to receive a first request for a first datum, query the cache metadata to determine whether the first datum is present in the main memory or the asymmetric cache device (ACD), retrieve the first datum from the main memory when the first datum is present in the main memory, retrieve the first datum from the ACD when the first datum is present in the ACD and not present in the main memory, store a copy of the first datum in the main memory when the first datum is present in the ACD and not present in the main memory, update the cache metadata to indicate that the copy of the first datum is stored in the main memory when the first datum is present in the ACD and not present in the main memory, and retrieve the first datum from the disk when the first datum is not present in the ACD and is not present in the main memory.