Write-aware random page initialization for non-volatile memory systems

Due to the high scalability and low power leakage, emerging non-volatile memories (NVMs) are promising to be integrated into memory hierarchy. However, NVMs have write issues, such as limited write endurance and high write energy. This paper observes that a large fraction of writes are caused by memory page initialization in the OS kernel stack. Thus, this paper proposes a write-aware random page initialization technique (WRPI) to reduce writes without sacrificing system security. Instead of initializing all bits of an allocated page, WRPI randomly initializes part bits. Moreover, WRPI sets the values of initialized bits to zeros or ones that require writing the least number of bits. The evaluation results show that WRPI can reduce writing bits to NVM memory by up to 21.0% and 11.3% on average, compared to the conventional page initialization. WRPI can also reduce the write energy consumption and the total energy consumption of NVM memory system by 14.0% and 5.8% on average, respectively.