Browse Prior Art Database

Safe Write Operation with Reading Neighbor Sectors

IP.com Disclosure Number: IPCOM000123797D
Original Publication Date: 1999-May-01
Included in the Prior Art Database: 2005-Apr-05
Document File: 1 page(s) / 33K

Publishing Venue

IBM

Related People

Ono, H: AUTHOR [+2]

Abstract

Data writing procedure for disk storage device is described when the servo signal just prior to the target data sector is defective. Conventional method reassigns alternative sectors when servo error happens under write operation. The described method prevents number of alternative sectors increasing too many. After detecting a servo error, the write operation is once terminated not to influence to the adjacent tracks which the target track locates at between. Next, the procedure try to read and save the data at the both adjacent tracks to the memory. And the target sector is written regardless the servo error. Confirmation process after writing is, to read back the adjacent tracks if they are broken or not.

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Safe Write Operation with Reading Neighbor Sectors

   Data writing procedure for disk storage device is described
when the servo signal just prior to the target data sector is
defective.  Conventional method reassigns alternative sectors when
servo error happens under write operation.  The described method
prevents number of alternative sectors increasing too many.  After
detecting a servo error, the write operation is once terminated not
to influence to the adjacent tracks which the target track locates at
between.  Next, the procedure try to read and save the data at the
both adjacent tracks to the memory.  And the target sector is written
regardless the servo error.  Confirmation process after writing is,
to read back the adjacent tracks if they are broken or not.  If each
of adjacent tracks got influence of the write operation, the original
data saved on the memory are written back, and an alternative sector
is assigned replacing the target sector.

   Here, the defective servo signal can be roughly estimated
referring to the prior signals based on the actuator dynamic model.
If the adjacent tracks are not saved, the estimator must predict and
correct the defective servo signal to be able to write on the track.
The above characteristics of described method reduces the dependency
to the servo estimation reliability, so that processor calculation
load gets down.  Then, this procedure allows not to use fast
processor with shorten process time of few disk revoluti...