General adaptive replacement policies

Abstract

We propose a general scheme for creating adaptive replacement policies with good performance and strong theoretical guarantees. Specifically, we show how to combine any two existing replacement policies so that the resulting policy provably can never perform worse than either of the original policies by more than a small factor. To show that our scheme performs very well with real application data, we derive a virtual memory replacement policy that adapts between LRU, loop detection, LFU, and MRU-like replacement. The resulting policy often performs better than all of the policies it adapts over, as well as two other hand-tuned adaptive policies from the recent literature.