TURBONFS: turbo nand flash search.

ABSTRACTNAND flash memories are popular due to their density and lower cost. However, due to serial access, NAND flash memories have slow read and write speeds. As the flash sizes increase to 64GB and beyond, searches through flash memories become painfully slow. In this paper, we present a hardware design enhancement to speed-up search through flash memories. The basic idea is to generate a small signature for every memory block and store them in a signature block(s). When a search is initiated, signature block is searched which produces reference of possible blocks where data might be contained, reducing the total number of read operations. The additional hardware has no impact on read access times or sequential write times. The additional step of signature generation increases the random write times by an average of 8-9%. Simulation experiments were performed for flash memory of size up to 16Gb. Simulation results show that the performance of searches improve by 4000X by using the proposed technique. The area overhead is estimated to be 5% of the memory area. The approach is easily extendible to NOR flashes and SSDs.