SYSTEMS AND METHODS FOR MANAGING DATA STORAGE

• US 20090006736A1
• Filed: 06/25/2008
• Published: 01/01/2009
• Est. Priority Date: 06/28/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Pantos, Roger, Batson, James D.
• Granted Patent: US 8,615,630 B2
• Time in Patent Office: Days
• US Class Current: 711/113
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 12/121 using replacement algorithms
• CPC Class Codes: H04N 21/4331 Caching operations, e.g. of an advertisement for later insertion during playback
• CPC Class Codes: H04N 21/4335 Housekeeping operations, e.g. prioritizing content for deletion because of storage space restrictions storage management, e.g. defragmentation G06F3/0604; unloading stored programs G06F9/445; storage management in file systems G06F16/10; buffering arrangements in a network node or in an end terminal in packet networks H04L49/90
• CPC Class Codes: H04N 21/47202 for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 7/173 with two-way working, e.g. subscriber sending a programme selection signal

Abstract

This invention is directed to a system by which data received by an electronic device from a server may be selectively stored in cache. The electronic device may define an anchor that is related to the current position of a playhead reading data stored in cache. The electronic device may then dynamically assign values to each data block of the received file based on the position of the anchor. As the anchor moves the value of data blocks changes, and new incoming data may replace less valuable data previously stored in cache.

Claims

1. A method for managing a received media file, comprising:

storing received data blocks of a media file in cache;

defining a dynamic anchor;

assigning a value to each data block of the media file based on the defined anchor; and

determining that cache is full;

pausing the transfer of the media file in response to determining that the value of the data blocks stored in cache exceed the value of a subsequently received data block.

2. The method of claim 1, further comprising:

receiving a data block;

determining the value of the received data block; and

comparing the determined value of the received data block with the assigned values of the data blocks stored in cache.

3. The method of claim 1, wherein defining further comprises:

identifying the position of the playhead in cache; and

defining the anchor before the identified position.

4. The method of claim 3, further comprising:

identifying a plurality of data blocks associated with the position of the playhead in cache;

locating the first of the identified plurality of data blocks in the media file; and

defining the anchor at the located first identified data block.

5. The method of claim 1, further comprising:

changing the position of the anchor;

modifying the values associated with each data block of the media file based on the changed position of the anchor; and

determining whether a data block not stored in cache has a higher modified value than a data block stored in cache.

6. The method of claim 5, further comprising resuming the transfer of the media file.

7. The method of claim 5, wherein changing further comprises changing the position of the anchor based on the position of the playhead.

8. The method of claim 1, further comprising:

identifying the subsequently received data block; and

determining the value of the identified received data block.

9. The method of claim 8, further comprising:

determining that the value of the identified received data block exceeds the value of a particular data block stored in cache;

evicting the particular data block stored in cache; and

storing the identified received data block in cache.

10. A method for managing a received media file, comprising:

storing received data blocks of a media file in cache;

defining a dynamic anchor;

assigning a value to each data block of the media file based on the defined anchor; and

replacing a particular data block stored in cache in response to receiving a data block having an assigned value that exceeds the value of the particular data block.

11. The method of claim 10, further comprising:

determining that cache is full; and

replacing in response to determining.

12. The method of claim 10, further comprising:

changing the position of the anchor;

assigning new values to each data block based on the changed position of the anchor; and

replacing based on the new values of the data blocks.

13. The method of claim 10, further comprising:

detecting the data block being currently read by the playhead; and

wherein changing further comprises

changing based on the detected data block.

14. The method of claim 13, further comprising:

identifying at least one data block associated with the detected data block; and

wherein defining further comprises

associating the anchor with the first of the identified and detected data blocks.

15. The method of claim 14, wherein the identified and detected data blocks comprise a video data block and an audio data block.

16. An electronic device operative to receive a media file, the electronic device comprising control circuitry, communications circuitry and a cache, the control circuitry operative to:

direct the communications circuitry to receive data blocks associated with a media file;

store the received data blocks in cache;

define a dynamic anchor in cache;

assign a value to each data block associated with the media file based on the defined dynamic anchor; and

direct the communications circuitry to pause the transfer of the data blocks in response to determining that the assigned value of a received data block is less than the assigned value of data blocks stored in cache.

17. The electronic device of claim 16, wherein the control circuitry is further operative to determine that the cache is full.

18. The electronic device of claim 16, wherein the control circuitry is further operative to:

play back the received media file;

determine the current position of the playhead in cache; and

define the dynamic anchor based on the determined current position of the playhead.

19. The electronic device of claim 18, wherein the control circuitry is further operative to:

identify a plurality of data blocks to be read in conjunction with the data block being read by the playhead; and

select the earliest of the identified plurality of data blocks; and

define the anchor at the selected data block.

20. The electronic device of claim 16, wherein the control circuitry is further operative to:

change the position of the anchor;

assign new values to each of the data blocks stored in cache; and

direct the communications circuitry to resume the transfer of the media file in response to determining that the assigned new value of a particular data block not stored in cache is more than the new assigned value of a data block stored in cache.

21. The electronic device of claim 20, wherein the control circuitry is further operative to direct the communications circuitry to resume the transfer by requesting the particular data block.

22. The electronic device of claim 16, wherein the control circuitry is further operative to assign the highest value to data blocks necessary for processing the received media file.

23. The electronic device of claim 22, wherein the necessary data blocks comprise data blocks for the table of contents of the media file.