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(fdutils.info)Sector skewing

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Sector skewing
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   Sector skewing is a technique that allows bigger throughputs.  It
does not increase the capacity of the disk. Sector skewing is only
relevant during formatting. Sector skewed disks are indistinguishable
from non-skewed disk by software, except for a different throughput.

   The principle of sector skewing is to start each track a little bit
later than the previous one, i.e. the first logical sector of the second
cylinder would for exemple lie near the sixth logical sector of the
first cylinder.  This is done in order to account for the time needed to
seek the drive head from the first cylinder to the second.  Without
skewing, the first sector would already have passed the drive head after
seeking, and we would need to wait for a whole rotation for it to come
back again.

   By default, superformat applies appropriate skewing to all formats,
and the listed throughput values refer to skewed disks. It is possible
to provide different values for the skew using the `--head_skew' and
`--track_skew' parameters. `head_skew' refers to the offset between
both sides of the same cylinder, and `track_skew' refers to the offset
of two consecutive cylinders. 0 means no skew.