A method, system, computer system, and computer-readable medium that
enable a copy of data to be converted from a full-data snapshot to a
space-saving snapshot, or vice versa, while retaining all the contents of
the snapshot. Full-data snapshots can be used for efficient read
operations and off-host processing operations. Space-saving snapshots can
be used to store multiple copies of primary data in a minimum amount of
storage space without consuming unnecessary storage space to store
duplicate copies of data that are not changing. The ability to convert
between full-data and space-saving snapshots enables organizational
storage, backup, and recovery needs to be met using the best type of
snapshot for a given operation.