Mitigating Write Amplification of Dual-mode Flash Memory

To improve the write performance of MLC flash memory, a conventional approach is to convert MLC blocks to SLC-mode blocks. Although the SLC-mode block has better write performance, it sacrifices half storage capacity. If the SLC-mode blocks are exhausted, they must be converted back to MLC blocks, which incurs the write amplification issue. To address this issue, we proposed a novel design to mitigate write amplification with the dual-mode block allocator and low latency programming scheme. The dual-mode block allocator rethinks the block allocation strategy and redesigns the traditional programming method of MLC flash memory with a low latency programming method. The experiment results showed that the proposed design could reduce write amplification up to 55%. Furthermore, the average write response time could be reduced up to 51%.