Synchronization optimization based upon allocation data

A non-transitory computer-readable medium storing instructions, which when executed by a processing device, cause the processing device to perform a method comprising:

• transmitting a request to a destination site for allocation information indicating whether or not each of a plurality of regions of a destination logical storage device is allocated;
• determining whether or not each of a plurality of corresponding regions of a source logical storage device is allocated;
• receiving the requested allocation information from the destination site;
• determining an allocation status of a first region of the plurality of regions of the source logical storage device and an allocation status of a corresponding first region of the plurality of regions of the destination logical storage device;
• and optimizing a synchronization process between the first region of the source logical storage device and the corresponding First region of the destination logical storage device based upon the determined allocation status of the first region of the source logical storage device and the determined allocation status of the corresponding first region of the destination logical storage device including, when one of the first region of the source or the destination logical storage device is determined to be unallocated based on the determined allocation status, comparing a checksum generated for a corresponding other one of the first region of the source or destination logical storage device that is determined to be allocated based on the determined allocation status against a predetermined checksum representing an unallocated region rather than reading and generating checksum for the first region of the source or the destination logical storage device that is determined to be unallocated.

An apparatus comprising:

• a processing device;
• and a memory coupled to the processing device, the memory storing instructions which, when executed by the processing device, cause the apparatus to:
• transmit a request to a destination site for allocation information indicating whether or not each of a plurality of regions of a destination logical storage device is allocated;
• determine whether or not each of a plurality of corresponding regions of a source logical storage device is allocated;
• receive the requested allocation information from the destination site;
• determine an allocation status of a first region of the plurality of regions of the source logical storage device and an allocation status of a corresponding first region of the plurality of regions of the destination logical storage device;
• and optimizing a synchronization process between the first region or the source logical storage device and the corresponding first region of the destination logical storage device based upon the determined allocation status of the first region of the source logical storage device and the determined allocation status of the corresponding first region of the destination logical storage device including, when one of the first region of the source or the destination logical storage device is determined to be unallocated based on the determined allocation status, comparing a checksum generated for a corresponding other one of the first region of the source or destination logical storage device that is determined to be allocated based on the determined allocation status with against a predetermined checksum representing an unallocated region rather than reading and generating checksum for the first region of the source or the destination logical storage device that is determined to be unallocated.