Alternate cylinder table to improve adjacent track interference problem
AssigneeHitachi Global Storage Technologies Netherlands B.V.
InventorsToshiaki Wada, Kazunari Tsuchimoto, Kaoru Umemura
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Abstract
Embodiments of the invention prevent data loss due to very frequent writing onto adjacent data tracks. In one embodiment, an alternate zone made up of multiple adjacent data tracks is formed by setting data tracks whose usage is to be prohibited for every other data track. The data updated very frequently and data not updated too frequently are recorded in the alternate zone. Data tracks for recording the data updated very frequently, and data tracks for recording data not updated too frequently, each have one cylinder of spacing. Data loss due to leakage fluxes can thus be prevented.
Claims21
A magnetic disk drive for use with a host apparatus in which data of low updating frequency and data of high updating frequency are recorded, said magnetic disk drive comprising:
- a magnetic disk having a data track group which includes a plurality of data tracks arranged adjacently to one another, from the innermost data track to the outermost data track;
- a look-up table having an alternate zone formed on said magnetic disk by, with respect to plural adjacent data tracks selected from the data track group, setting usage prohibition for every other data track, wherein the usage-prohibited data tracks are not used for data recording;
- and
- a processor that refers to said look-up table, skips the usage-prohibited data tracks by executing a write command sent from the host apparatus in order to record the data of low updating frequency, and a write command sent from the host apparatus in order to record the data of high updating frequency, and writes the data of low updating frequency and the data of high updating frequency onto data tracks of the alternate zone.
A magnetic disk drive for use with a host apparatus in which data of low updating frequency and data of high updating frequency are recorded, said magnetic disk drive comprising:
- a magnetic disk with a plurality of data tracks each having an absolute address allocated in order of physical arrangement;
- an alternate cylinder table having blind tracks generated by, with respect to absolute addresses of the data tracks, setting up a flag for every other absolute address, wherein the blind tracks are not used for data recording;
- a recording medium for storing said alternate cylinder table;
- and
- a processor that refers to the flag set up in said alternate cylinder table, skips the blind tracks by executing a write command sent from the host apparatus in order to record the data of low updating frequency, and a write command sent from the host apparatus in order to record the data of high updating frequency, and writes the data of low updating frequency and the data of high updating frequency onto data tracks of alternate zone.
A recording method in which a host apparatus records data of low updating frequency and data of high updating frequency in a magnetic disk drive, said method comprising:
- setting up an alternate zone in which data tracks for recording data in part of a storage region on a magnetic disk of the magnetic disk drive, and blind tracks not used for data recording, are arranged, one by one, in alternate positions;
- a first recording step of writing the data of low updating frequency onto data tracks of the alternate zone by executing, while skipping the blind tracks, a write command sent from the host apparatus in order to record the data of low updating frequency;
- a second recording step of writing the data of high updating frequency onto other data tracks of the alternate zone by executing, while skipping the blind tracks, a write command sent from the host apparatus in order to record the data of high updating frequency.
A magnetic disk drive for use with a host apparatus in which data of low updating frequency and data of high updating frequency are recorded, said magnetic disk drive comprising:
- a magnetic disk;
- a look-up table in which data tracks for recording data in part of a storage region on said magnetic disk, and blind tracks not used for data recording, are set so as to be arranged, one by one, in alternate positions;
- a recording medium for storing said look-up table;
- a processor configured to control said magnetic disk drive;
- and
- a program stored within said magnetic disk or said recording medium, said program being readable by said processor;
- wherein said program is executable by said processor to perform:
- a first recording step of writing the data of low updating frequency Onto data tracks of alternate zone by executing, while skipping the blind tracks, a write command sent from the host apparatus in order to record the data of low updating frequency;
- and
- a second recording step of writing the data of high updating frequency Onto other data tracks of the alternate zone by executing, while skipping the blind tracks, a write command sent from the host apparatus in order to record the data of high updating frequency.
Dependencies are inferred from the claim text.