

Stephen Bates
There can be no doubt that NAND flash based Solid State Drives (SSDs) are having a massive impact on the design and implementation of data-centers. SSDs allow data-centers to accelerate applications that are deployed as cloud services as well as providing a low latency tier of storage and reducing the Total Cost of Ownership (TCO) of the data-center infrastructure. The huge demand for flash by data-center vendors and cloud service providers is tempered only by the cost per GB for an SSD. As such, there is huge pressure on SSD vendors to produce high capacity, high endurance SSDs for less cost. One way to achieve this goal is to use smaller lithography flash to permit more bits per unit area and hence less cost per bit. However as one scales down NAND flash the endurance of the flash tends to also drop. We can compensate for this by using more advanced error correction and media management techniques and for this reason. In this talk we will look at the trends in NAND flash and SSDs with regard to keeping SSDs on this downward trend in terms of cost per bit. We will look at schemes such as LDPC error correcting codes and how they can increase the endurance of an SSD whilst also reducing the cost of the SSD.