Significance of Write References on Nonvolatile Buffer Cache and its Implication on Hit Ratio and the Optimal MIN Replacement Algorithm

Abstract

Performance studies of buffer caches have generally been done with write references ignored. In this study, we show that once we consider write references in buffer caches that include nonvolatile memory, the traditional hit ratio performance measure is no longer an accurate representation, and that the disk access ratio should be used. We also show that in regards to this measure, the MIN replacement algorithm is either non-optimal or non-applicable.