MOBILE DEVICE AND METHOD OF MANAGING DATA USING SWAP THEREOF

• US 20140164686A1
• Filed: 12/10/2013
• Published: 06/12/2014
• Est. Priority Date: 12/11/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Park, Il, Choi, JinHyuck
• Granted Patent: US 9,116,631 B2
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 12/08 in hierarchically structured memory systems, e.g. virtual memory systems
• CPC Class Codes: G06F 12/12 Replacement control
• CPC Class Codes: G06F 2212/171 Portable consumer electronics, e.g. mobile phone
• CPC Class Codes: G06F 2212/214 Solid state disk
• CPC Class Codes: G06F 2212/401 Compressed data
• CPC Class Codes: G06F 3/0647 Migration mechanisms

Abstract

A mobile device includes a storage configured to store data, a buffer memory configured to include a swap victim buffer area and a normal data area, and an application processor configured to select page data to be swapped from the normal data area and to perform a swapping operation on the selected page data. The swapping operation performs an instant swapping operation or a lazy swapping operation according to a data type of the selected page data.

Claims

1. A mobile device, comprising:

a storage configured to store data;

a buffer memory configured to include a swap victim buffer area and a normal data area; and

an application processor configured to select page data to be swapped from the normal data area and to perform a swapping operation on the selected page data,

wherein the swapping operation performs an instant swapping operation where the page data is shifted from the normal data area to the storage or a lazy swapping operation where the page data is shifted from the normal data area, through the swap victim buffer area, to the storage according to a data type of the selected page data.

2. The mobile device of claim 1, wherein for the lazy swapping operation, the application processor is configured to compress the page data, to store the compressed page data in the swap victim buffer area, and to shift the compressed page data to the storage.

3. The mobile device of claim 2, wherein the storage is a flash memory and the buffer memory is a DRAM.

4. The mobile device of claim 2, wherein when the compressed page data stored in the swap victim buffer area is required, the application processor is configured to read the compressed page data stored in the swap victim buffer, to decompress the compressed page data, and to store the decompressed data in the normal data area.

5. The mobile device of claim 1, wherein for the instant swapping operation, the application processor is configured to shift the page data from the normal data area to the storage without using the swap victim buffer area.

6. The mobile device of claim 5, wherein when a compression ratio of the selected page data is lower than a threshold value, the application processor is configured to perform the instant swapping operation

7. A mobile device, comprising:

a nonvolatile memory;

a DRAM configured to include a swap victim buffer and a normal data area; and

an application processor coupled to the nonvolatile memory and the DRAM,

wherein when a swap of page data stored in the normal data area is required, the application processor is configured to perform an instant swapping operation or a lazy swapping operation according to a type of the page data,

wherein the instant swapping operation shift the page data to the nonvolatile memory without using the swap victim buffer, and

wherein the lazy swapping operation compresses the page data and shifts the compressed data to the nonvolatile memory through the swap victim buffer area.

8. The mobile device of claim 7, wherein the application processor determines a type of the page data according to a compression ratio of the page data.

9. The mobile device of claim 7, wherein the application processor comprises a direct memory access configured to shift the compressed page data stored in the swap victim to the nonvolatile memory.

10. The mobile device of claim 7, wherein the compressed page data is shifted in a unit of a data chunk from the swap victim buffer to the nonvolatile memory.

11. The mobile device of claim 10, wherein the unit of the data chunk is set such that a data transfer time of the data chunk by the direct memory access is equal to or shorter than a data transfer time of the data chunk by the application processor, wherein the data transfer time of the data chunk by the direct memory access includes a programming time of the DMA.

12. The mobile device of claim 10, wherein the unit of the data chunk has a size of 32 KB or more.

13. A data managing method of an application processor, comprising:

determining a data type of page data stored in a normal data area of a DRAM; and

performing a lazy swapping operation on the page data when the determined data type is a lazy type and an instant swapping operation on the page data when the determined data type is an instant type.

14. The data managing method of claim 13, wherein the determining a data type of page data stored at a DRAM comprises:

compressing the page data;

determining a compression ratio of the page data; and

deciding a data type of the page data as the lazy type when the compression ratio of the page data is higher than a threshold value and as the instant type when the compression ratio of the page data is not higher than the threshold value.

15. The data managing method of claim 14, further comprising:

storing the data type of the page data.

16. The data managing method of claim 13, further comprising:

predicting the data type of the page data using header information of the page data; and

when the data type is the lazy type, performing a compression operation on the page data; and

when the data type is not the lazy type, skipping the compression operation on the page data.

17. The data managing method of claim 14, further comprising:

storing the compression ratio of the page data.

18. The data managing method of claim 17, further comprising:

reading the stored compression ratio; and

if the read compression ratio is higher than the threshold value, reading the page data from the DRAM to compress the read page data, and wherein if the read compression ratio is not higher than the threshold value, compression of the page data is skipped.

19. The data managing method of claim 13, further comprising:

detecting a feature of the page data or a process associated with the page data; and

varying the threshold value according to the detection result.

20. The data managing method of claim 13, wherein the determining of the data type of page data stored in the DRAM comprises:

compressing part of the page data;

determining whether a compression ratio of the part of the page data is higher than a threshold value; and

when the compression ratio is higher than the threshold value, compressing the remaining of the page data and deciding the data type as the lazy type; and

when the compression ratio of the page data is not higher than the threshold value, deciding the data type as the instant type without compressing the remaining of the page data.

21. The data managing method of claim 13, wherein the instant swapping operation further comprises:

shifting the page data from the DRAM to a storage.

22. The data managing method of claim 13, wherein the lazy swapping operation comprises:

shifting the page data to a swap victim buffer area of the DRAM in a compressed data format.

23. The data managing method of claim 22, wherein the swap victim buffer area is configured to include a plurality of entries, each of which is configured to have a plurality of page entries, wherein the page data is stored in a page entry of the plurality of the entries, wherein the page data is stored in the compressed data format.

24. The data managing method of claim 23, wherein the plurality of page entries of each of the plurality of entries is managed using a linked list.

25. The data managing method of claim 23, wherein the lazy swapping operation further comprising:

shifting the compressed page data from the swap victim buffer area to a storage.

26. The data managing method of claim 25, wherein the compressed page data is selected when the compressed page data is earliest stored in the swap victim buffer area.

27. The data managing method of claim 26, further comprising:

reading compressed page data from the plurality of entries when the compressed page data stored at the swap victim buffer area is required;

decompressing the compressed page data; and

storing the decompressed page data in the normal data area.

28. The data managing method of claim 13, wherein the lazy swapping operation performed using a direct memory access and the instant swapping operation is performed by a processor.

29. An application processor, comprising:

a DRAM interface;

a flash memory interface;

a direct memory access; and

a processor configured to determine whether a swapping operation is required, configured to receive page data to be swapped through the DRAM interface, and configured to perform the swapping operation on the page data in an instant swapping operation or a lazy swapping operation according to a data type of the page data,

wherein when the lazy swapping operation, the processor is configured to compress the page data and output the compressed page data through the DRAM interface and the direct memory access is configured to control a data path between the DRAM interface and the flash memory interface to shift the outputted compressed page data from the DRAM interface to the flash memory interface.

30. The application processor of claim 29, wherein the data type of the page data is determined by a compression ratio of the page data.

31. The application processor of claim 29, wherein the data type of the page data is determined by header information of the page data without compressing the page data.

32. The application processor of claim 29, wherein the instant swapping operation is performed without compressing the page data.