Patent ID: 7733589

Claim:
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.