CA-Dedupe: content-aware deduplication in SSDs

Flash memories have been around for many years because of their high performance compared to HDDs. But flash memories have a limited lifespan, and they will wear prematurely if used in write-intensive usages. Solutions such as wear leveling, compression and deduplication have been proposed to address this issue. Deduplication is a proper way to improve flash memories’ lifespan, but deduplication methods proposed in previous works usually impose a significant delay on write operations. This paper provides an intelligent method for data deduplication on flash memories which works by categorizing write requests based on their contents and types. In this scheme, calculated metadata for write requests is placed in separate categories and during deduplication procedure, the search operation is performed in one category. As a result, the proposed method improves the search delay and the deduplication rate significantly. Simulation results show that the proposed method improves delay of write operations by 32%, when compared to other methods, and achieves the deduplication rate of 69.8%.