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Date: Wed, 4 Dec 2013 11:15:41 +0100
From: Polytropon <freebsd@edvax.de>
To: Erich Dollansky <erichsfreebsdlist@alogt.com>
Subject: Re: Minimum size of a UFS partition
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On Wed, 4 Dec 2013 15:59:07 +0800, Erich Dollansky wrote:
> Hi,
> 
> does anybody know how small a partition for UFS can get?
> 
> I would need a very small partition of even below 1.44 MB.

That should be possible by applying specific options to newfs
for fine-tuning. The size of the "administrative structures"
can be controlled by tuning -S, -b and -f. Also -o, -r and -m
will have an effect here. Note that -s is given in sectors.
Creating a UFS volume directly on a device should leave all
the control to you, using newfs. If you need to create a
partition for it (GPT via gpart, MBR via gpart, MBR via
fdisk and bsdlabel) things will probably get more complicated
because more "overhead" will be involved. In a "normal" case,
newfs will automatically detect the size of what the file
system is going to be created on (e. g. da0p1, da0s1, or da0)
and will span across the usable space automatically, so
maybe a combination of "create a small partition somehow"
and "make UFS use the partition optimally" would be a possible
way to go.

See "man newfs" and "man tunefs" for details, as well as the
documentation of possibly involved partitioning tools. :-)




-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...