Patent ID: 7353423

Claim:
A method of improving read performance of a plurality of parity storage devices during an operation in a storage system, comprising: selecting one or more parity storage devices; designating each selected parity storage device as a replicated-parity device; writing a plurality of data elements and a plurality of parity elements to a stripe in the storage system; for each replicated-parity storage device, replicating the parity elements in the stripe to form a plurality of mirrored parity elements on the replicated-parity device; associating the replicated-parity device with the stripe; reading the mirrored parity elements from the replicated-parity device during the operation, using one IO access to the replicated-parity device; and rotating permuted stripes within the storage system with respect to a preceding permuted stripe, wherein the rotating comprises aligning at least some of the data elements with the parity elements, and further aligning at least some of the data elements with the mirrored parity elements.