Patent ID: 7970996

Claim:
A method for constructing an array of storage devices, comprising: establishing a selected number of storage devices in the array of storage devices, each selected storage device storing data in blocks; establishing a selected number of data storage blocks for a parity block; establishing a plurality of parity sets, a parity set having the number of data blocks and having a set parity block, the parity sets chosen so that each data storage block is in more than one parity set; computing the set parity block for each parity set; and storing each set parity block on a storage device of the array selected to store parity blocks (hereinafter a parity storage device for each of the plurality of parity sets), to store more than one parity block on each parity storage device, with an exception that two parity blocks for a same data storage location are precluded from being stored on the same is parity storage device.