Memory systems including a duplicate removing filter module that is separate from a cache module

摘要

A memory system includes a cache module configured to store data. A duplicate removing filter module is separate from the cache module. The duplicate removing filter module is configured to receive read requests and write requests for data blocks to be read from or written to the cache module, selectively generate fingerprints for the data blocks associated with the write requests, selectively store at least one of the fingerprints as stored fingerprints and compare a fingerprint of a write request to the stored fingerprints.

主权项

1. A memory system comprising:
a cache memory configured to store data; a backend data store; a duplicate removing filter separate from the cache memory and configured to: receive read requests and write requests for data blocks to be read from or written to the cache memory; generate fingerprints for the data blocks associated with the write requests and store at least one of the fingerprints in the duplicate removing filter; determine a match between a fingerprint of a data block of a write request and the at least one stored fingerprints; send a logical block address of the write request and a cache reference corresponding to the matched fingerprint to the cache memory in response to a single condition indicating that the fingerprint of the data block matches the at least one stored fingerprints; in response to receiving a write request as a write-back operation, send the logical block address of the write request, the fingerprint of the write request and the data block to the cache memory; and in response to identifying a write request as a write-thru operation, the duplicate removing filter is configured to send the data block to the backend data store without performing duplicate removal.