Effective Management Method of Spare Area Allocation for Sector and Cylinder Defects
Original Publication Date: 1995-May-01
Included in the Prior Art Database: 2005-Mar-30
Matsui, T: AUTHOR [+2]
Disclosed is an effective management method for allocating spare areas for defect areas on magnetic disks.
Effective Management Method of Spare Area Allocation for
an effective management method for allocating
spare areas for defect areas on magnetic disks.
In a Hard
Disk Drive (HDD) system, read errors can happen if a
defect exists on a track of the disk.
errors happen, an HDD system assigns a spare area is
allocated for writing the data instead of the defect track.
occur on servo areas and also data areas.
Conventional HDD systems execute the different spare area assigning
operations for defects in servo areas and for defects in data areas.
exist in the data area, a spare sector is assigned
for alternating the defect data sector. When defects exist in a
servo area, a spare cylinder is assigned. This is because the servo
area's defect influences the seek operation of the system, then the
cylinder having the defect servo area is replaced to the spre
cylinder. Therefore, if a defect exists on a servo area, the data
tracks including many data sectors relating to the defective servo
area can not be used. Further, a conventional HDD system must
prepare a spare cylinder region and spare sector region separately,
consequently, the space for the spare region becomes very large.
provides a new method for allocating alternate
regions for defective areas on a disk in a HDD system.
When a defect exists in a servo region...