Consideration for effectively handling parallel workloads on public cloud system

Abstract: We retrieved and analyzed parallel storage workloads of the FUJITSU K5 cloud service to clarify how to build cost-effective hybrid storage systems. A hybrid storage system consists of fast but low-capacity tier (first tier) and slow but high-capacity tier (second tier). And, it typically consists of either SSDs and HDDs or NVMs and SSDs. As a result, we found that 1) regions for first tier should be assigned only if a workload includes large number of IO accesses for a whole day, 2) the regions that include a large number of IO accesses should be dynamically chosen and moved from second tier to first tier for a short interval, and 3) if a cache hit ratio is regularly low, use of the cache for the workload should be cancelled, and the whole workload region should be assigned to the region for first tier. These workloads already have been released from the SNIA web site.