Patent ID: 9195412
Filing Date: 2015-11-24
Classification: G06F

Abstract:
1. A system for transforming an in-use RAID array from a first array configuration having at least a first parameter to a second array configuration having at least a second parameter while preserving a logical data structure of the in-use RAID array, comprising: an extent reservation component configured to reserve one or more reserved extents; a data migration component configured to read unmigrated data from an area of the in-use RAID array arranged according to the first array configuration and writing the data to an area of the in-use RAID array arranged according to the second array configuration using the one or more reserved extents to store at least first migrated data and using one or more further extents to store at least second migrated data; a first I/O component configured to perform I/O operations according to the first array configuration on the unmigrated data prior to its reading by the data migration component; and a second I/O component configured to perform I/O operations according to the second array configuration on the at least first migrated data and the at least second migrated data after the data is written by the data migration component; wherein the data migration component is configured to read the unmigrated data from an end of the area of the in-use RAID array arranged according to the first array configuration in a direction towards a start of the in-use RAID array, such that data migration begins by moving data in extents at the end of the area of the in-use RAID array arranged according to the first array configuration to the area of the in-use RAID array arranged according to the second array configuration.