Abstract: Some embodiments provide a system that provides a virtual disk in a computer system. During operation, the system stores data for the virtual disk in a virtual disk file on the computer system. Next, the system loads a differential location data structure corresponding to a snapshot of the virtual disk into memory on the computer system and processes input/output (I/O) operations to the virtual disk using the differential location data structure and the virtual disk file. Finally, the system periodically generates a new snapshot of the virtual disk by transactionally committing changes made to the differential location data structure by the I/O operations to the virtual disk file.

Abstract: Some embodiments provide a system that provides a virtual disk in a computer system. During operation, the system stores data for the virtual disk in a virtual disk file on the computer system. Next, the system loads a differential location data structure corresponding to a snapshot of the virtual disk into memory on the computer system and processes input/output (I/O) operations to the virtual disk using the differential location data structure and the virtual disk file. Finally, the system periodically generates a new snapshot of the virtual disk by transactionally committing changes made to the differential location data structure by the I/O operations to the virtual disk file.