Error correction for disk storage media
Embodiments of the invention provide methods and systems for improving the reliability of data stored on disk media. Logical redundancy is introduced into the data, and the data within a logical storage unit is divided into sectors that are spatially separated by interleaving them with sectors of other logical storage units. The logical redundancy and spatial separation reduce or minimize the effects of localized damage to the storage disk, such as the damage caused by a scratch or fingerprint. Thus, the data is stored on the disk in a layout that improves the likelihood that the data can be recovered despite the presence of an error that prevents one sector from being read correctly.
1. A method of developing a data layout on a disk storage media to meet a desired error rate, the method comprising:
calculating an amount of data per logical storage unit based on standard error characteristics, parameters of the disk storage media including disk capacity, a desired error rate, and acceptable loss of capacity of the disk storage media for error protection;
developing a layout of data according to the amount of data per logical storage unit; and
recording data onto a disk according to the developed layout of data,
wherein the amount of data per logical storage unit indicates a number of sectors to be included in each logical storage unit, and
wherein the developing a layout of data includes:
dividing data for storage into at least one logical storage unit, each logical storage unit comprising at least two sectors; and
interleaving the logical storage units to achieve spatial separation of the sectors from a same logical storage unit.
2. The method of claim 1 , wherein the standard error characteristics comprise dimensions and distribution of standard errors.
3. The method of claim 2 , wherein the standard errors comprise fingerprints.
4. The method of claim 2 , wherein the standard errors comprise scratches.
5. The method of claim 1 , wherein the parameters of the disk storage media comprise physical dimensions of the disk storage media.
6. The method of claim 1 , wherein the desired error rate is specified by a standards organization.
7. The method of claim 1 , wherein the acceptable loss of capacity of the disk storage media is approximately 10%.
8. A computer program product for developing a data layout on a disk storage media to meet a desired error rate, the computer program product stored on a computer readable medium and adapted to perform the operations of:
calculating an amount of data per logical storage unit based on standard error characteristics, parameters of the disk storage media including disk capacity, a desired error rate, and acceptable loss of capacity of the disk storage media for error protection;
developing a layout of data according to the amount of data per logical storage Unit; and
recording data onto a disk according to the developed layout of data,
wherein the amount of data per logical storage unit indicates a number of sectors to be included in each logical storage unit, and
wherein the developing a layout of data includes the operations of:
dividing data for storage into at least one logical storage unit, each logical storage unit comprising at least two sectors; and
interleaving the logical storage units to achieve spatial separation of the sectors from a same logical storage unit.
9. The computer program product of claim 8 , wherein the standard error characteristics comprise dimensions and distribution of standard errors.
10. The computer program product of claim 9 , wherein the standard errors comprise fingerprints.
11. The computer program product of claim 9 , wherein the standard errors comprise scratches.
12. The computer program product of claim 8 , wherein the parameters of the disk storage media comprise physical dimensions of the disk storage media.
13. The computer program product of claim 8 , wherein the desired error rate is specified by a standards organization.
14. The computer program product of claim 8 , wherein the acceptable loss of capacity of the disk storage media is approximately 10%.