Patent ID: 7930496
Filing Date: 2011-04-19
Classification: G06F

Abstract:
1. A method, comprising: initiating an operation to move a logical volume from a first storage location to a second storage location; establishing a relationship between the first and second storage locations to copy data in the logical volume from the first storage location to the second storage location to implement the move of the logical volume from the first to the second storage locations; receiving a read request to data in the logical volume while moving the data in the logical volume from the first storage location to the second storage location; determining, in response to the read request, whether the requested data is at a first copy of the logical volume in the first storage location or a second copy of the logical volume at the second storage location; returning the requested data from the determined first or second copy of the logical volume while the logical volume is being copied from the first storage location to the second storage location; receiving a request to write data to the logical volume while copying the data in the logical volume from the first copy to the second copy, wherein once the relationship indicates that the requested data has been copied from the first copy of the logical volume to the second copy, all reads to the requested data are directed to the second copy; writing the write data to the second copy of the logical volume at the second storage location; removing indication of the relationship between the first and second storage locations in response to copying all the data indicated in the relationship from the first storage location to the second storage location resulting in the relocation of the logical volume to the second copy; and freeing space in the first storage location for data copied from the first storage location to the second storage location pursuant to the relationship established between the first and second storage locations to relocate the logical volume.