The ability to guarantee performance to thousands of applications at once has garnered praise from analysts and enterprises alike. Without this guarantee, cloud providers will not be able to meet the rising performance requirements of enterprise customers. Given the compelling advantages for performance isolation and guaranteed storage QoS, it’s no wonder that storage vendors are adding QoS features to their products. We recently discussed some of the simplistic approaches to QoS offered by storage systems, however the ability to guarantee performance to applications is not as simple as adding a new bullet point to a lengthy feature list.
Being able to guarantee application performance in all situations – including failure scenarios, system overload, variable workloads, and elastic demand – requires an architecture built from the ground up specifically to guarantee storage Quality of Service. Trying to bolt Quality of Service onto an architecture that was never designed to deliver performance guarantees is like strapping a jet engine to a VW Beetle. The wheels will come off just when you get up to speed.