A study of the number of spare sectors in a hard disk
Hiroyuki Hirakoshi, Hiroaki Sandoh · Electronics and Communications in Japan (Part III Fundamental Electronic Science) · 1997
Hard disks in recent years have had a factory-sealed structure. For this reason, when a failure occurs in any mechanical component of a hard disk, it cannot be repaired. In such a case, the hard disk must be replaced by a new one. This is called a hard disk failure. On the other hand, a hard disk undergoes sector failures where the data on a failed sector will be lost but the hard disk can be repaired by logically substituting a spare sector for the failed sector. However, a malfunction or a hard disk failure of a hard disk will occur when the total number of sector failures exceeds the number of spare sectors prepared in a hard disk. This study discusses methods for designing the number of spare sectors, proposing two models along with numerical examples. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 3, 80(8): 66–74, 1997