Pre-organization of Data

• US 20120311000A1
• Filed: 06/03/2011
• Published: 12/06/2012
• Est. Priority Date: 06/03/2011
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Post, Daniel Jeffrey, Herman, Ken, Neuenschwander, Erik C., Crosby, Daniel E., Chan, David Michael, Nham, Benjamin H.
• Granted Patent: US 8,738,882 B2
• Time in Patent Office: Days
• US Class Current: 707/824
• CPC Class Codes: G06F 12/02 Addressing or allocation; Relocation program address sequencing G06F9/00; arrangements for selecting an address in a digital store G11C8/00
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 16/1847 specifically adapted to static storage, e.g. adapted to flash memory or SSD
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 3/0616 in relation to life time, e.g. increasing Mean Time Between Failures [MTBF]
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

In a method of writing data to a file system on a solid state drive, a file stream is opened for writing to a file in the file system. A life expectancy value predicting a length of time the data to be written will be stored in the file system is attached to the file stream. The data is written to the file stream and stored on the solid state storage device according to the life expectancy value attached to the data. In one embodiment, a unique identifier may be used as the life expectancy value for writing a group of related files predicted to be stored in the file system for substantially the same length of time. The life expectancy value may be predicted based on a file type of the file being written. The life expectancy value may be stored as metadata for the file being written.

Claims

1. A method of writing data to a file system in a non-volatile memory, the method comprising:

opening a file stream for writing to a file in the file system;

attaching a life expectancy value to the file stream, the life expectancy value being a prediction of a length of time the data to be written will be stored in the file system;

writing the data to the file stream; and

causing the data written to the file stream to be written to the non-volatile memory according to the life expectancy value attached to the data.

2. The method of claim 1, further comprising acquiring a unique identifier for writing a group of related files in the file system, the related files being predicted to be stored in the file system for substantially the same length of time, the unique identifier being the life expectancy value attached to each file stream used to write data for each of the files in the group of related files.

3. The method of claim 1, wherein the life expectancy value is a binary value.

4. The method of claim 1, wherein the life expectancy value is predicted based on a file type of the file being written to.

5. The method of claim 1, wherein the life expectancy value is stored as metadata for the file being written.

6. The method of claim 1, wherein the non-volatile memory comprises flash memory.

7. A processor based device comprising:

a processor;

a non-volatile memory coupled to the processor; and

an operating system that is executed by the processor, the operating system performing operations for writing data to a file system in the non-volatile memory, the operations including

opening a file stream for writing to a file in the file system,

attaching a life expectancy value to the file stream, the life expectancy value being a prediction of a length of time the data to be written will be stored in the file system,

writing the data to the file stream, and

closing the file stream and thereby causing the data written to the file stream to be stored in the non-volatile memory according to the life expectancy of the data.

8. The processor based device of claim 7, the operating system performing operations further comprising acquiring a unique identifier for writing a group of related files in the file system, the related files being predicted to be stored in the file system for substantially the same length of time, the unique identifier being the life expectancy value attached to each file stream used to write data for each of the files in the group of related files.

9. The processor based device of claim 7, wherein the life expectancy value is a binary value.

10. The processor based device of claim 7, wherein the operating system performing operations further comprising predicting the life expectancy value based on a file type of the file being written.

11. The processor based device of claim 7, wherein the operating system performing operations further comprising storing the life expectancy value as metadata for the file being written.

12. The processor based device of claim 7, wherein the non-volatile memory comprises flash memory.

13. A device controller for accessing a non-volatile memory organized into a plurality of erasable blocks, the device controller comprising:

a data controller for communicating with a source of data;

a bus controller for communicating with the non-volatile memory and the source of data; and

control circuitry performing operations including

directing the data controller to receive data to be initially written to the non-volatile memory and to receive an associated life expectancy value,

selecting one of the plurality of erasable blocks to receive the data according to the associated life expectancy value, and

directing the bus controller to write the received data to the selected erasable block of the non-volatile memory.

14. The device controller of claim 13, further comprising a buffer controller for communicating with one or more buffers coupled to the non-volatile memory, wherein the control circuitry performs further operations including directing the buffer controller to write the received data to a buffer, and directing the bus controller to write the contents of the buffer to the selected erasable block of the non-volatile memory.

15. The device controller of claim 14, wherein the control circuitry performs further operations including selecting a buffer to receive the data according to the associated life expectancy value.

16. The device controller of claim 13, wherein the life expectancy value is a binary value and the device controller selects one of two erasable blocks.

17. The device controller of claim 13, wherein the control circuitry performs operations further including storing the life expectancy value as metadata for the data being written.

18. The device controller of claim 13, wherein the non-volatile memory comprises flash memory.

19. An electronic device comprising:

a non-volatile memory organized into a plurality of erasable blocks; and

a device controller coupled to the non-volatile memory and a data bus, the device controller performing operations including

receiving data to be initially written to the non-volatile memory and an associated life expectancy value,

selecting one of the plurality of erasable blocks to receive the data according to the associated life expectancy value, and

writing the received data to the selected erasable block.

20. The electronic device of claim 19, further comprising one or more buffers coupled to the non-volatile memory, wherein the device controller performs further operations including writing the received data to a buffer, and writing the contents of the buffer to the selected erasable block of the non-volatile memory.

21. The electronic device of claim 19, wherein the device controller performs further operations including selecting a buffer to receive the data according to the associated life expectancy value.

22. The electronic device of claim 19, wherein the life expectancy value is a binary value and the device controller selects one of two buffers.

23. The electronic device of claim 19, wherein the device controller performs operations further including storing the life expectancy value as metadata for the data being written.

24. The electronic device of claim 19, wherein the non-volatile memory comprises flash memory.