International Business Machines Corporation

James A O'Conner

Karl Allen Nielsen

Robert Akira Kubo

Carl Evan Jones

James Lee Hafner

David Frank Mannenbach

David Ray Kahler

Krishnakumar S Rao

Krishnakumar Rao Surugucchi

A RAID system is provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a 'new data, unconfirmed' state. The state of written data is periodically checked, such as with a timer. If the data is in the 'new data, unconfirmed' state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a &#x201c;single dropped write confirmed&#x201d; state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a &#x201c;confirmed good&#x201d; state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an &#x201c;unquantifiable&#x201d; state.

Detection and correction of dropped write errors in a data storage system

Methods are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a 'new data, unconfirmed' state. The state of written data is periodically checked, such as with a timer. If the data is in the 'new data, unconfirmed' state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a &#x201c;single dropped write confirmed&#x201d; state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a &#x201c;confirmed good&#x201d; state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an &#x201c;unquantifiable&#x201d; state.

Method, system and computer program product are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a 'new data, unconfirmed' state. The state of written data is periodically checked, such as with a timer. If the data is in the 'new data, unconfirmed' state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a &#x201c;single dropped write confirmed&#x201d; state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a &#x201c;confirmed good&#x201d; state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an &#x201c;unquantifiable&#x201d; state.

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Ulster Park, NY, United States of America

James A O'Conner