some random thoughts on mkfs

[David Solan]

Oooopps.  Somehow the end of my "random thoughts on mkfs" got
censored by USENET.  Here they are again:


Here is an example of what I mean.  After you have initialized a
floppy diskette to be 42 cylinders(tracks) and 10 physical sectors
per track, doing an mkfs by itself on this floppy results in the
following:

mkfs /dev/fp021
---- ----------
slice 1
bytes per logical block = 1024
total logical blocks = 415
total inodes = 96
gap (physical blocks) = 2
cylinder size (physical blocks) = 20 

The "415" above means 830 "physical blocks", as far as mkfs is
concerned.  So, to get more inodes, do the following:

mkfs /dev/fp021 830:144 2 20
---- ---------- ------- - --
bytes per logical block = 1024
total logical blocks = 415
total inodes = 144
gap (physical blocks) = 2
cylinder size (physical blocks) = 20 

In the first case above, a df -t command (on the mounted file system)
results in:

/mnt      (/dev/fp021):      812 blocks      94 i-nodes
 total:      830 blocks      96 i-nodes

 And, in the second case, a df -t command gives:

 /mnt      (/dev/fp021):      806 blocks     142 i-nodes
  total:      830 blocks     144 i-nodes

Keep It Short and Simple.

The 3.51 Utilities package has a detailed description of the mkfs
command in the UNIX System V User's Manual, Volume 1 -- look it
up!!!  ("when all else fails, read the directions").

	David  Solan
	Objective Programming Incorporated
	Post Office Box 123
	Norwalk,  CT  06856
	Voice: (203) 866-6900
	attmail: dsolan
	USENET: gizzmo!kdavid

-- 
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                                                {codas,u1100a}-----\
David Solan                            rutgers!rochester!pcid!kodak!gizzmo!mark
                                          {lazlo,ethos,fthood}-----/