Patent ID: 8060714

Claim:
A method to perform initialization comprising: writing I/Os received at a data protection appliance to a first delta marking stream, the first delta marking stream comprising metadata of locations and differences in the I/O data between a first volume and a second volume; marking a first point in the first delta marking stream; generating a copy of the first volume at the first point; marking a second point in the first delta marking stream after generating the copy of the first volume at the first point; providing a second delta marking on or after the second point in the first delta marking stream; determining dirty locations between the second volume and the copy; and after determining the dirty locations between the second volume and the copy: freeing I/O data from the second delta marking stream; freeing I/O data from first delta marking stream up to the first point, wherein the copy is generated from one of taking a snapshot or taking a clone of the first volume.