1. A computer-implemented system for backing up data, the system comprising: at least one processor and an operatively associated storage device, wherein the at least one processor is programmed to: execute a tracking application; execute a file system driver; and execute a file system filter driver, wherein the file system filter driver is programmed to: receive a start tracking request; receive a plurality of write input/output (I/O) requests from the application; record a set of current changes to an address of a block to be modified by the write I/O request for each of the plurality of I/O requests; forward the write I/O request to the file system driver; receive a lock request; determine that the lock request is the first lock request received since receipt of the start tracking request; and in response to receiving the second lock request after the first lock request, copy the current changes to frozen changes, clear the current changes, receive a second lock request, and discard current changes after initiating a merger of the current changes.