US Patent 11836052 Data backup and recovery management using allocated data blocks

A data backup and recovery method and system using allocated data blocks include identifying a first snapshot associated with a virtual machine; accessing changed block tracking data associated with data changes occurred in the virtual machine, the data changes corresponding to a set of changed data blocks; accessing block allocation status data associated with the set of changed data blocks; identifying one or more allocated data blocks from the set of changed data blocks that are associated with allocated status based on the block allocation status data; and storing the one or more allocated data blocks to a storage device.