Efficient Management of PCM-based Swap Systems with a Small Page Size

Abstract

Due to the recent advances in non-volatile memory technologies such as PCM, a new memory hierarchy of computer systems is expected to appear. In this paper, we explore the performance of PCM- based systems and discuss how this system can be managed efficiently. Specifically, we introduce three management techniques. First, we show that the page fault handling time can be reduced by attaching PCM on DIMM slots, thereby eliminating the software stack overhead of block I/O and the context switch time. Second, we show that it is effective to reduce the page size and turn off the read-ahead option under the PCM system where the page fault handling time is sufficiently small. Third, we show that the performance is not degraded even with a DRAM memory under a PCM device; this leads to the reduction of DRAM's energy consumption significantly compared to HDD-based systems. We expect that the result of this paper will lead to the transition of the legacy system structure of large memory - slow swap to a new paradigm of small memory - fast swap.