Improvements in Storage Energy Efficiency via Storage Subystem Cache and Tiering

The energy efficiency of storage subsystems in terms of Idle Capacity/Watt, IOPs/Watt, and MB/s/Watt can be significantly improved through the deployment of Capacity Optimization Methods (COMs). These features affect the apparent capacity, IO rate and throughput (MB/s) and therefore also the target “green” metrics cited above. This paper describes a case study of the compound effect of two features, that of storage subsystem cache and tiered storage on the primary metrics of the SNIA Emerald Power Efficiency Specification using both the former random workloads and the recently adopted “Hot Band” Workload as the comparative test stimuli. Also described is the potential energy efficiency benefit of several additional COM types

Learning Objectives

Compare the characteristics of the Hot Band, cache friendly workload with that of a completely random stimulus
Quantify the performance benefits of adequate storage subsystem cache when exposed to a cache friendly workload
Describe the effect of cache assistance on the workload as seen by the “back end” or traditional spinning media portion of the storage
Quantify the subsequent deployment of storage tiering on the overall performance measurements and associated Emerald Power Efficiency Metrics