4.3BSD-UWisc/man/cat8/mkfs.8
MKFS(8) UNIX Programmer's Manual MKFS(8)
NAME
mkfs - construct a file system
SYNOPSIS
/etc/mkfs [ -N ] special size [ nsect [ ntrack [ blksize [
fragsize [ ncpg [ minfree [ rps [ nbpi [ opt ] ] ] ] ] ] ] ]
]
DESCRIPTION
N.B.: file system are normally created with the _n_e_w_f_s(8)
command.
_M_k_f_s constructs a file system by writing on the special file
_s_p_e_c_i_a_l unless the -N flag has been specified. The numeric
size specifies the number of sectors in the file system.
_M_k_f_s builds a file system with a root directory and a
_l_o_s_t+_f_o_u_n_d directory. (see _f_s_c_k(8)) The number of i-nodes
is calculated as a function of the file system size. No
boot program is initialized by _m_k_f_s (see _n_e_w_f_s(8).)
The optional arguments allow fine tune control over the
parameters of the file system. Nsect specify the number of
sectors per track on the disk. Ntrack specify the number of
tracks per cylinder on the disk. Blksize gives the primary
block size for files on the file system. It must be a power
of two, currently selected from 4096 or 8192. Fragsize
gives the fragment size for files on the file system. The
fragsize represents the smallest amount of disk space that
will be allocated to a file. It must be a power of two
currently selected from the range 512 to 8192. Ncpg speci-
fies the number of disk cylinders per cylinder group. This
number must be in the range 1 to 32. Minfree specifies the
minimum percentage of free disk space allowed. Once the
file system capacity reaches this threshold, only the
super-user is allowed to allocate disk blocks. The default
value is 10%. If a disk does not revolve at 60 revolutions
per second, the rps parameter may be specified. If a file
system will have more or less than the average number of
files the nbpi (number of bytes per inode) can be specified
to increase or decrease the number of inodes that are
created. Space or time optimization preference can be
specified with opt values of ``s'' for space or ``t'' for
time. Users with special demands for their file systems are
referred to the paper cited below for a discussion of the
tradeoffs in using different configurations.
SEE ALSO
fs(5), dir(5), fsck(8), newfs(8), tunefs(8)
M. McKusick, W. Joy, S. Leffler, R. Fabry, ``A Fast File
System for UNIX'', _A_C_M _T_r_a_n_s_a_c_t_i_o_n_s _o_n _C_o_m_p_u_t_e_r _S_y_s_t_e_m_s _2,
3. pp 181-197, August 1984. (reprinted in the System
Printed 12/27/86 May 21, 1986 1
MKFS(8) UNIX Programmer's Manual MKFS(8)
Manager's Manual, SMM:14)
BUGS
There should be some way to specify bad blocks.
Printed 12/27/86 May 21, 1986 2