Post by George Crump (thank you)
Cloud Providers and enterprises must be able to guarantee performance to specific applications or groups of applications. They also need ways to distribute some of their storage management workload directly to the users or ‘interests’ they support. In the cloud provider use case this is typically divided up by subscriber. In the enterprise this may be divided up by line of business (finance) or by service type (Exchange group). In both cases the overall goal is to drive down the cost by making storage self-serviceable while assuring predictable application performance.
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Storage CH Blog 