Disk drive having two tiered defect list comprising marginal and reserved data sectors

摘要

The present invention provides a method of operating a disk drive having data sites on a disk for recording data thereon. The disk drive is connectable to a host computer and maintains a defect table comprising defective sites reportable to the host computer. The method includes the step of discovering a defective data site on the disk. The defective data site is bounded with a first tier of marginal data sites which are selected based on their proximity to the defective data site. The first tier of marginal data sites is bounded with a second tier of reserved data sites which are selected based on their proximity to the first tier of marginal data sites. The locations of the defective data site, the first tier of marginal data sites and the second tier of reserved data sites are stored in a defect table. The defective data sites and the first tier of marginal data sites are marked as defective sites reportable to the host. A plurality of data sites which are not included within the first tier or second tier of marginal data sites are allocated as spare data sites, while the second tier of data sites are neither allocated as normal data sites, spare data sites nor defective data sites.