Using File Systems for Non-volatile Main Memory Management

Non-volatile (NV) memory is next generation memory. It provides fast access speed comparable to DRAM and also persistently stores data without power supply. These features enable NV memory to be used as both main memory and secondary storage. While the active researches have been conducted on its use for either main memory or secondary storage, they were conducted independently. This paper proposes the integrated memory management methods, by which NV memory can be used as both main memory and secondary storage. The proposed methods use file systems as their basis for NV memory management. Such integration enables the memory allocation for processes and files from the same source, and processes can take advantage of a large amount of physical memory used for both main memory and storage. We implemented the proposed memory management methods in the Linux kernel. The evaluation results performed on a system emulator show that the memory allocation costs of the proposed methods are comparable to that of the existing DRAM and are significantly better than those of the page swapping.