Patent ID: 9239797
Filing Date: 2016-01-19
CPC Classification: G06F

Claim Text:
1. A method for implementing enhanced data caching and takeover of non-owned storage devices in a computer system comprising: providing each of a first storage device controller and a second storage device controller with a cache memory; connecting a plurality of storage devices to the first storage device controller and second storage device controller, and assigning respective ones of the storage devices assigned to the first storage device controller, and respective other ones of the storage devices assigned to the second storage device controller; during normal run-time, each storage device controller performing the steps of: writing data to its cache memory and writing a cached mirrored copy in the cache memory of the other storage device controller, and storing a cached mirrored copy in its cache memory from cached write data of the other storage device controller; validating cached write data after writing data to its cache memory by reading the write data from its cache memory; responsive to detecting any error on the read, marking the storage device controller as failed and reset the failed storage device controller; responsive to the failing of a storage device controller, a surviving storage device controller performing the steps of: queuing host read/write operations for storage devices assigned to the surviving storage device controller; and testing from the surviving storage device controller's cache memory cached mirrored copy of the failed storage device controller's cache before taking ownership of all storage devices.