Browse Prior Art Database

Formatting Method for Hard Disk Drive

IP.com Disclosure Number: IPCOM000109392D
Original Publication Date: 1992-Aug-01
Included in the Prior Art Database: 2005-Mar-24
Document File: 2 page(s) / 51K

Publishing Venue

IBM

Related People

Kisaka, M: AUTHOR [+3]

Abstract

Disclosed is a technique for improving throughput of a hard disk drive by using a new disk format.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Formatting Method for Hard Disk Drive

       Disclosed is a technique for improving throughput of a
hard disk drive by using a new disk format.

      RBA (Relative Block Address) is used for accessing a hard disk
drive.  RBA is a consecutive number starting from 0 for each sector.
By using RBA, a host system has been relieved from caring about
numbers of cylinders, heads and sectors.

      A new formatting method is proposed. The new points are:
      - Cylinder change will occur within the same head.
      - On even cylinder, numbering will start from head 0 to max
head.
      - On an odd cylinder, it will start from max head to head 0 (or
in reverse direction).

      An example assuming the number of head, 4 and that of sector,
10 is shown in Fig. 1.

      By this new method, a head change is no longer required on
cylinder change. Sequential disk access time (throughput) is improved
by
                (Time to head change) x (Number of cylinders)

      Decision logic on sequential access is shown in Fig. 2. For
random access, it will be achieved in a similar way.

      In prior art, RBA is numbered from cylinder 0, head 0, sector 0
and continue to the max and repeat cyclically, as shown in Fig. 3. By
this formatting method, on accessing from the last RBA of cylinder to
next RBA, head change and cylinder change are required at RBA 39 to
40 and RBA 79 to 80 in Fig. 3.