Offset protection data in a RAID array

摘要

A system and method for offset protection data in a RAID array. A computer system comprises client computers and data storage arrays coupled to one another via a network. A data storage array utilizes solid-state drives and Flash memory cells for data storage. A storage controller within a data storage array is configured to store user data in a first page of a first storage device of the plurality of storage devices; generate intra-device protection data corresponding to the user data, and store the intra-device protection data at a first offset within the first page. The controller is further configured to generate inter-device protection data corresponding to the first page, and store the inter-device protection data at a second offset within a second page in a second storage device of the plurality of storage devices, wherein the first offset is different from the second offset.

主权项

1. A computer system comprising:
a client computer comprising hardware and configured to send read and write requests over a network; a data storage subsystem coupled to the network configured to receive the read and write requests, wherein the subsystem comprises a plurality of data storage locations on a plurality of storage devices; wherein the data storage subsystem further comprises a storage controller, wherein for a given redundant array of independent drives (RAID) stripe, the storage controller is configured to:
store user data in a first page of a first storage device of the plurality of storage devices;generate first intra-device protection data configured to protect the user data;store the first intra-device protection data at a first offset within the first page;generate second intra-device protection data configured to protect data stored in a second page of a second storage device of the plurality of storage devices;store the second intra-device protection data in the second page at a second offset within the second page, wherein the second offset is at a different position relative to the second page than the first offset is relative to the first page;generate inter-device protection data configured to protect the first intra-device protection data of the first page; andstore the inter-device protection data at a third offset within the second page, wherein the third offset is at a same position relative to the second page as the first offset relative to the first page.