Patent ID: 9021191
Filing Date: 2015-04-28
Classification: G06F

Abstract:
1. A computer program product for managing Input/Output (I/O) requests to a storage device, the computer program product comprising a computer readable storage medium having computer readable program code embodied therein that executes to perform operations, the operations comprising: receiving a write request having write data for a logical address, wherein data for the logical address is at a first physical location in the storage device and has an indicated version number; writing the write data to a second physical location in the storage device; determining whether a preserve mode, which indicates whether previous versions of data are to be maintained, is enabled in response to writing the data to the second physical location; in response to determining that the preserve mode is enabled, indicating the second physical location as having a current version number of the logical address and indicating the first physical location to have a previous version number of the logical address.