Operations

6.3.2 Alternating processing for defective sectors

The following two types of technology are used for alternating processing:

(1) Sector slip processing

In this method, defective sectors are not used (thereby avoiding the effects of defects), and each defective sector is assigned to the next contiguous sector that is normal.

Depending on the format defined at shipment from the plant, this processing is performed for defective sectors.

Figure 6.5 shows an example where sector (physical) 5 with cylinder 0 and head 0 is defective.

Cylinder 0 Head 0

Sector (physical)

778 779 780

Defec- tive sector

(Not used)

 

777

778

779

Note: When an access request for sector 5 is issued, physical sector 6 must be accessed instead of physical sector 5.

Figure 6.5 Sector slip processing

(2) Track slip processing

In this method, defective tracks not used (there by avoiding the effects of defects), and each defective track is assigned to the next contiguous track that is normal.

Depending on the format defined at shipment from the plant, this processing is performed for defective tracks.

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Fujitsu MHU2100AT manual Alternating processing for defective sectors, Sector slip processing, Track slip processing