Granted Patent B2

US 8,301,948 · App. 12/538,367 · Granted Oct 30, 2012

Abstract

Claims (63)

1. A system comprising:

a recording media capable of storing data;

a processor configured to:

determine that the system is in an idle state of input/output requests;

copy first data symbols from a location of the recording media;

correct the first data symbols using a first error-correcting code;

write second data symbols including the corrected first data symbols to the location on the recording media with a second error-correcting code;

determine an error number for the second data symbols;

compare the error number to a threshold; and

based on the comparison, record the second error-correction code or alternately keep the first error-correction code.

2. The system of claim 1 wherein the first data symbols are written with a weaker error-correcting code and the second data symbols are written with a stronger error-correcting code.

3. The system of claim 1 wherein the first data symbols are written with a stronger error-correcting code and the second data symbols are written with a weaker error-correcting code.

4. The system of claim 1 wherein the recording media is a flash memory.

5. The system of claim 1 wherein the processor is further configured to:

create a desired writing of the first data symbols by encoding the first data based on the first error-correcting code.

6. A method comprising:

determining that a processor is in an idle state of input/output requests;

determining that a first error number for first data written on a recording disk with a strong error-correcting code is above a first threshold error number;

determining a set of bits based on the first data and the strong error-correcting code;

writing the set of bits to the recording disk by applying a first phase shift to a write control signal;

reading second data from the recording disk, the second data being the read written set of bits;

comparing the second data to the set of bits;

determining a second error number for the second data;

comparing the second error number to a second threshold error number; and

based on the comparing:

writing the second data to the recording disk with a first error-correcting code; and

freeing a region of the recording disk storing the strong error-correcting code.

7. The method of claim 6 wherein a timing of a magnetic field generated by a magnetic write head is controlled by the write control signal.

8. The method of claim 6 wherein a timing of the light from a light source used for heating the disk is controlled by the write control signal.

9. The method of claim 6 wherein the first error-correcting code requires less bits than the strong error-correcting code on the recording disk.

10. The method of claim 6 wherein the recording disk is a magnetic hard disk.

11. The method of claim 6 wherein the recording disk is a patterned magnetic hard disk.

12. The method of claim 6 wherein the recording disk is a thermally assisted recording magnetic disk.

13. The method of claim 6 wherein the recording disk is an optical disk.

14. The method of claim 6 further comprising:

creating the desired writing of the first data by encoding the first data based on the strong error-correcting code.

15. The method of claim 6 further comprising:

compacting the first data written on the recording hard disk in response to writing the second data with the first error-correcting code.

16. The method of claim 6 further comprising:

storing information on the recording disk indicating sectors of the recording disk that have been compacted.

17. The method of claim 6 further comprising:

rewriting the set of bits to the recording disk applying a second phase shift to the write control signal;

reading third data from the recording disk, the third data being the read rewritten set of bits; and

comparing the third data to the set of bits.

18. A non-transitory computer readable medium comprising a plurality of instructions to manipulate a processor, the plurality of instructions comprising:

instructions to determine that a processor is in an idle state of input/output requests;

instructions to determine that a first error number for first data written on a magnetic hard disk with a strong error-correcting code is above a first threshold error number;

instructions to determine a set of bits based on the first data and the strong error-correcting code;

instructions to write the set of bits to the recording disk by apply a first phase shift to a write control signal;

instructions to read second data from the recording disk, the second data being the read written set of bits;

instructions to compare the second data to the set of bits;

instructions to determine a second error number for the second data;

instructions to compare the second error number to a second threshold error number; and

instructions to write the second data to the magnetic hard disk with a first weak error-correcting code in response to the comparing.

19. The computer readable medium of claim 18 wherein the first weak error-correcting code requires less bits than the strong error-correcting code on the magnetic hard disk.

20. The computer readable medium of claim 18 wherein the magnetic hard disk is a patterned magnetic hard disk.

21. The computer readable medium of claim 18 further comprising:

instructions to determine an offset margin for the first phase shift; and

instructions to delete the strong error-correcting code data on the magnetic hard disk.

22. The computer readable medium of claim 21 wherein the offset margin is a number of phase shifts that provide a corrected bit in the second data.

23. The computer readable medium of claim 18 further comprising:

instructions to compact the first data written on the magnetic hard disk in response to writing the second data with the weak error-correcting code.

24. The computer readable medium of claim 18 wherein the first phase shift is varied on a bit by bit basis.

Assignments (6)