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AssigneeInternational Business Machines Corporation
InventorsYoshihiko Terashita, Tohru Sumiyoshi, Hiroyuki Miyoshi
Estimating the term…
When data are transferred to a cache from disk drives, through a back end I/F unit, a redundant code verifier of a data path controller compares write-history information (a Destaging Counter (DC) value) embedded in a redundant code of the data with a DC value embedded in a redundant code of a corresponding parity, thereby verifying whether the data are imprecise. In addition, in a case where the data are updated, the redundant code verifier makes a similar verification when old data to be used for creating a parity are read. When the data are not imprecise, a redundant code generator of the data path controller adds to new data and the parity a redundant code into which a new DC value has been embedded. When the data are imprecise, a controller informs a host of an occurrence of a problem through a front end I/F unit.
A device for detecting a data error in a memory, comprising:
A method to detect imprecise data, comprising:
A computer program product comprising a computer useable medium including a computer readable program, wherein the computer readable program when executed on the computer causes the computer to perform operations comprising:
A controller for a data storage system that comprises a plurality of data storage disks comprising a data storage memory and a cache, said controller comprising a first interface for coupling to the data storage memory and a second interface for coupling to a host, said controller comprising redundant code verifier circuitry, responsive to data being transferred to the cache from the data storage memory to compare a first Destaging Counter (DC) value, indicative of write-history information, that is contained in a redundant code of the data with a second DC value that is contained in a redundant code of corresponding data integrity data to thereby verify whether the data being transferred is in error.
Dependencies are inferred from the claim text.