A system for optimizing a process of determining a location of data identified by a virtual hard drive address includes a virtual hard drive, a hypervisor, a plurality of chained files and a table. The plurality of chained files includes a first file comprising a delta of a master file and each subsequent file comprising a delta of a previous file in the plurality of chained files. The table enumerates associations between each of a plurality of virtual hard drive addresses with one of the master file and a file in the plurality of chained files. The virtual hard drive stores the master file, the plurality of chained files, and the table. The hypervisor intercepts a request to access data at a virtual hard drive address and identifies, based on the table, a file containing the requested data and responds to the request with access to the requested data.