FEBRE: A Fast and Efficient Bit-Flipping Reduction Technique to Extend PCM lifetime

Abstract

Minimizing flipped bits per write is an effective method to extend the lifetime of Phase Change Memory (PCM). However, there still remains the challenge of reaching the minimal flips without significantly compromising the speed of read/write operation. Toward this end, we propose a differential-write technique FEBRE: a Fast and Efficient Bit-flipping Reduction technique to Extend PCM lifetime. Its basic idea is to generate multiple encoded vectors from one writing data vector, so the vector with the minimal number of flips can be selected for writing. Specifically, we design a new scheme to rapidly generate multiple highly random encoded vectors from one writing data, and propose an innovative pipelined encoding algorithm to further accelerate this procedure. Compared to the current state-of-the-art technique Pseudo-Random Encoding Scheme (PRES), the FEBRE technique proposed in the present study can improve the encoding speed by at least 229%, reduce decoding operations by at least 45%, and reduce bit flips by at most 5.13%.