Red: An efficient replacement algorithm based on REsident Distance for exclusive storage caches

This paper presents our replacement algorithm named RED for storage caches. RED is exclusive. It can eliminate the duplications between a storage cache and its client cache. RED is high performance. A new criterion Resident Distance is proposed for making an efficient replacement decision instead of Recency and Frequency. Moreover, RED is non-intrusive to a storage client. It does not need to change client software and could be used in a real-life system. Previous work on the management of a storage cache can attain one or two of above benefits, but not all of them. We have evaluated the performance of RED by using simulations with both synthetic and real-life traces. The simulation results show that RED significantly outperforms LRU, ARC, MQ, and is better than DEMOTE, PROMOTE for a wide range of cache sizes.