Patent ID: 8195978

Claim:
An apparatus to detect and replace failed data storage, the apparatus comprising: a read module that reads an error correcting code (ECC) chunk stored across a plurality of memory devices of an array of memory devices, the ECC chunk comprising both data and an error correcting code derived from the data and wherein at least one of the memory devices of the array stores parity data derived from data stored on each memory device of the plurality of memory devices storing the ECC chunk; an ECC module that determines that the ECC chunk has more errors than are correctable using the error correcting code for the ECC chunk; and an isolation module that tests individual memory devices of the plurality of memory devices to locate a failed memory device by: substituting, within the data of the ECC chunk, replacement data for data of a first one of the memory devices to form a first substitute ECC chunk, the replacement data derived from the parity data; substituting, within the data of the ECC chunk, replacement data for data of a second one of the memory devices to form a second substitute ECC chunk in response to the ECC module determining that the first substitute ECC chunk has more errors than are correctable using the error correcting code for the ECC chunk; and determining that the second one of the memory devices is the failed memory device in response to the ECC module determining that errors in the second substitute ECC chunk are correctable using the error correcting code for the ECC chunk.