Digital device for performing booting process and control method therefor

A digital device comprising:

• a first memory;
• a second memory configured to store a snapshot image generated based on page data stored in the first memory;
• and
• a processor configured to:
• remove duplicate page data from among the page data stored in the first memory by storing location information about the duplicate page data in a mapping table;
• compare page data remaining after removing the duplicate page data with page data pre-stored in the second memory;
• selectively remove the duplicate page data from the page data pre-stored in the second memory depending on whether the duplicate page data is located in a hot cluster of the second memory as a result of the comparison;
• generating a snapshot image based on page data remaining after the selective removing;
• and
• booting the digital device using the generated snapshot image in a subsequent powering on of the digital device,
• wherein the processor is further configured to:
• compare the page data remaining after primary deduplication in the first memory with page data included in blocks stored in the second memory to generate a comparison result;
• increment a use counter for the blocks by a predetermined value when duplicate page data is present in the blocks based on the comparison result;
• designate a hot block and a hot cluster based on a value of the block use counter for a cluster including a predetermined number of the blocks located on the second memory;
• and
• store the hot cluster in the second memory and update a cluster table with designation information for the hot cluster, the hot cluster including at least some of the duplicate page data remaining after the primary deduplication.

A method for controlling a digital device for performing a booting process, the digital device including a first memory and a second memory, the second memory including a hot cluster and a cold cluster, the method comprising:

• removing, by a processor in the digital device, duplicate page data from among page data stored in the first memory by storing location information about the duplicate page data in a mapping table;
• comparing, by the processor, page data remaining after the removing with page data pre-stored in the second memory;
• selectively removing, by the processor, the duplicate page data from the page data pre-stored in the second memory depending on whether the duplicate page data is located in the hot cluster or the cold cluster of the second memory as a result of the comparison;
• generating, by the processor, a snapshot image based on page data remaining after the selective removing;
• in response to a portion of the duplicate page data belonging to the cold cluster, allocating a new cluster and continuously storing the duplicate page data in the new cluster;
• and
• booting the digital device using the generated snapshot image in a subsequent powering on of the digital device,
• wherein the cold cluster refers to a cluster having a certain number of cold blocks, and
• wherein the cold blocks refer to blocks having a number of times of duplicate use less than or equal to a certain value.