Patent ID: 7797498

Claim:
A garbage data collection method performed during a communication cycle of a plurality of communication cycles of a computing device having memory including writeable non-volatile memory, the garbage data collection method comprising: performing a mark phase during a communication cycle, the mark phase for making a first list, the first list being an address list including addresses of objects to be deleted from the memory; performing a first sweep phase during the communication cycle to delete objects listed in the first list from the memory, wherein the performing of the sweep phase comprises: calculating a residual time up to a predetermined time limit after processing an external command; after calculating the residual time, deleting objects listed in the first list from the memory during the calculated residual time; and updating the first list to include addresses of remaining objects listed in the first list of objects to be deleted which cannot be deleted within the calculated residual time, and storing the updated first list in the memory separately from the objects so as to prevent deletion of the first list.