Patent ID: 7409512

Claim:
A method comprising: maintaining state information, wherein the state information is associated with a plurality of regions of a working volume, wherein the state information indicates which of the regions of the working volume are valid, wherein the maintaining the state information comprises updating the state information in response to the working volume being accessed, and wherein the updating the state information comprises writing to a storage device that stores the state information; delaying synchronization of data stored in a first region of the plurality of regions with associated redundant data, in response to the state information indicating that the first region is invalid, wherein the synchronization is delayed until the first region is accessed; receiving a read request for application data within a one of the regions, wherein prior to the receiving, the state information indicates that the one of the regions is invalid; and writing redundant data to the working volume, in response to the read request, wherein the redundant data corresponds to the application data in the one of the regions, and wherein the updating the state information comprises updating the state information to indicate that the one of the regions is valid, in response to the writing the redundant data.