Latency-aware strategy for static list caching in flash-based web search engines

Caching is a widely used technique to boost the performance of search engines. Based on the observation that the speed gap between the random access of flash-based solid state drive and its sequential access is much inapparent than that of magnetic hard disk drive, we introduce a new static list caching algorithm which takes the block-level access latency into consideration. The experimental results show that the proposed policy can reduce the average disk access latency per query by up to 14\% over the state-of-the-art algorithms in the SSD-based infrastructure. Besides, the results also reveal that our new strategy outperforms other existing algorithms even on HDD-based architecture.