Selective shingled magnetic recording scheme
Assigneeinodyn NewMedia GmbH
InventorLothar Pantel
Life of this patent
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Abstract
A selective band management scheme for storage devices is disclosed that may be used in connection with shingled magnetic recording (SMR). SMR uses bands consisting of tracks separated by guard regions. The replacement of a defective sector may be attained by selecting a suitable guard region and by displacing the selected guard region onto the physical location of the defective sector. The boundaries of the bands may be shifted. The portion of the disk surface that is necessary for the guard regions may simultaneously function as a spare sector area for defective sectors without additional space requirements. In at least one embodiment, guard regions are selectively placed onto tracks with an elevated number of primary defects by means of an optimization algorithm.
Claims25
A method for replacing at least one defective section on a disk surface without using sector slipping and spare sectors, comprising:
- a) providing a plurality of tracks configured for shingled magnetic recording at least in an area of said disk surface, the tracks being grouped into bands by means of entire tracks designated as circular guard regions,
- b) determining that at least one defective section is located on a track in a first band,
- c) selecting the preceding guard region at least if said defective section is located in the upper half of said first band,
- d) selecting the succeeding guard region at least if said defective section is located in the lower half of said first band,
- e) displacing at least the selected guard region onto the physical location of said defective section, wherein the entire circular guard region is displaced in the radial direction of said disk surface such that the radius of the circular guard region is changed,
- f) converting the former physical location of said selected guard region into one or more newly constituted tracks and integrating said one or more newly constituted tracks into the regular tracks of a second band that is adjacent to said first band,
- g) storing data at least on said one or more newly constituted tracks.
A method for replacing at least one defective section on a disk surface without using sector slipping and spare sectors, comprising:
- a) providing a plurality of tracks configured for shingled magnetic recording at least in an area of said disk surface,
- b) determining the quality level of each track within said area,
- c) sorting said plurality of tracks by quality level and selecting at least tracks with a low quality level by means of an optimization algorithm, taking into account the radial distances between the selected tracks such that defined criteria for the distribution of the selected tracks are met,
- d) placing guard regions at least on the selected tracks such that entire tracks are designated as circular guard regions.
A storage device capable of replacing at least one defective section on a disk surface without using sector slipping and spare sectors, comprising:
- a) a plurality of tracks configured for shingled magnetic recording at least in an area of said disk surface, the tracks being grouped into bands by means of entire tracks designated as circular guard regions,
- b) a write element, a read element, and
- c) a control unit configured to:
- i) determine that at least one defective section is located on a track in a first band,
- ii) select the preceding guard region at least if said defective section is located in the upper half of said first band,
- iii) select the succeeding guard region at least if said defective section is located in the lower half of said first band,
- iv) displace at least the selected guard region onto the physical location of said defective section, wherein the entire circular guard region is displaced in the radial direction of said disk surface such that the radius of the circular guard region is changed,
- v) convert the former physical location of said selected guard region into one or more newly constituted tracks, which are integrated into the regular tracks of a second band that is adjacent to said first band,
- vi) store data at least on said one or more newly constituted tracks.
Dependencies are inferred from the claim text.