The Truth About MapReduce Performance on SSDs.

Solid-state drives (SSDs) are increasingly being considered as a viable alternative to rotational hard-disk drives (HDDs). In this paper, we investigate if SSDs improve the performance of MapReduce workloads and evaluate the economics of using PCIe SSDs either in place of or in addition to HDDs. Our contributions are (1) a method of benchmarking MapReduce performance on SSDs and HDDs under constant-bandwidth constraints, (2) identifying cost-per-performance as a more pertinent metric than cost-per-capacity when evaluating SSDs versus HDDs for performance, and (3) quantifying that SSDs can achieve up to 70% higher performance for 2.5× higher cost-per-performance.