W-Buddy: Wear-out-aware memory allocator for SCRAM-based low power mobile systems

Abstract

Since recently emerging storage class RAM (SCRAM) devices are power-efficient, byte-addressable, and non-volatile, they are expected to replace the power-hungry DRAM in mobile consumer devices. However, SCRAM has a limited number of program and erase cycling, requiring a wear-leveling technique. Since the locality in memory access pattern may intensify the discriminated wearing of memory blocks, it is required to change the operating systems such that memory accesses are distributed evenly over all memory space for wear-leveling. We propose a novel memory allocator, called W-Buddy, which selects a free memory chunk to be allocated considering the wear-outs of memory chunks. Our experimental results show that the proposed W-Buddy achieves fourteen time longer lifetime compared with the conventional buddy memory allocator.