Patent ID: 8307135
Filing Date: 2012-11-06
Classification: G06F

Abstract:
1. A method for operating a storage system including a plurality of operational elements and a plurality of host interfaces, comprising: determining respective queue lengths of input/output requests to the plurality of operational elements; determining an average queue length in each of the operational elements; determining a performance benchmark for the storage system, the performance benchmark being the average queue length of the operational elements; assigning a first deviation from the performance benchmark, the first deviation comprising a first predetermined percentage above the performance benchmark that is set by a user; assigning a second deviation from the performance benchmark, the second deviation comprising a second predetermined percentage below the performance benchmark that is set by the user, wherein the first deviation and the second deviation are configured to maintain the average queue lengths within a predetermined range of queue lengths; comparing each respective queue length and the first deviation; comparing each respective queue length and the second deviation; identifying, in response to the comparison, each under-performing operational element and each over-performing operation element among the plurality of operational elements, an under-performing operational element comprising a queue length greater than the average queue length plus the first deviation and an over-performing operational element comprising a queue length less than the average queue length minus the second deviation; receiving one or more requests at one of the plurality of host interfaces for specified items of the data directed to an under-performing operational element; in response to the receiving the one or more requests, re-directing at least a portion of the one or more requests from the under-performing operational element to one or more other operational elements that are not under-performing; and re-directing one or more requests from one or more operational elements that are not over-performing to an identified over-performing operational element, wherein the first predetermined percentage and the second predetermined percentage are the same percentage.