Disclosed is a method and apparatus for incrementally baking up a data
volume. In one embodiment of the method, the data volume is created in a
first memory, and a point-in-time (PIT) copy of the data volume is
created at time T0. First data of the data volume is modified between
times T0 and T1, wherein time T1 is subsequent to time T0. Second data of
the data volume is copied to a second memory after time T1. The second
data of the data volume is modified after the second data is copied to
the second memory. Lastly, data of the PIT copy is overwritten with (1)
the copy of the second data stored in the second memory and (2) the
modified first data of the data volume.