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.\" @(#)diskpart.8 6.6 (Berkeley) 3/16/91
.Nd calculate default disk partition sizes
is used to calculate the disk partition sizes based on the
default rules used at Berkeley.
Available options and operands:
Tables suitable for inclusion in a device driver
An entry suitable for inclusion in the disk
is generated; for example,
The size of the disk may be limited to
space is normally left in the last partition on the disk
for a bad sector forwarding table, although this space
is not reflected in the tables produced. The space reserved
is one track for the replicated copies of the table and
sufficient tracks to hold a pool of 126 sectors to which bad sectors
are mapped. For more information, see
option is intended for other controllers which reserve some space at the end
of the disk for bad-sector replacements or other control areas,
even if not a multiple of cylinders.
The disk partition sizes are based on the total amount of
space on the disk as given in the table below (all values
are supplied in units of sectors). The
is, by convention, used to access the entire physical disk.
The device driver tables include
the space reserved for the bad sector forwarding table in the
those used in the disktab and default formats exclude reserved tracks.
In normal operation, either the
partition is used, or the
are variable-sized, occupying whatever space remains after allocation
of the fixed sized partitions.
If the disk is smaller than 20 Megabytes, then
.Dq Li disk too small, calculate by hand .
.Bl -column Partition 20-60\ MB 61-205\ MB 206-355\ MB 356+\ MB
Partition 20-60 MB 61-205 MB 206-355 MB 356+ MB
a 15884 15884 15884 15884
b 10032 33440 33440 66880
d 15884 15884 15884 15884
e unused 55936 55936 307200
h unused unused 291346 291346
If an unknown disk type is specified,
will prompt for the required disk geometry information.
Most default partition sizes are based on historical artifacts
(like the RP06), and may result in unsatisfactory layouts.
flag, alternate disk names are not included
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