Re: [gentoo-user] Freeing up disk space problem!!

[Alex Schuster <wonko@wonkology.org>]

Neil Bothwick writes:

> On Tue, 28 Feb 2012 14:01:50 +0100, Alex Schuster wrote:
> 
> > If you instantly need more space, reduce the amount of reserved space
> > for the superuser, which is 5% as default:
> > tune2fs -m 2 /dev/your/partition
> > Don't reduce it to 0, the lower this value is, the more fragmentation
> > you will get.
> 
> Why is that? I would have expected more usable space to reduce the need
> for fragmentation. I routinely use 0 on non-system filesystems.

I read this often, and to me it seems to make sense. When a file system
is nearly full, writing a last big file will make the file being
cluttered along all those tiny places where some free space is still
left. And this probably already happens to some extent before the
filesystem is completely full. 

Now, which values for reserved percentage are good, I don't know.
This probably depends much on the typical size of files on that partition,
and usage patterns. For large movies on your data partition, it probably
does not matter, but for my system partitions (/root, /usr, /var, /tmp,
portage stuff) I just keep it at 5%.

With the benefit that I can instantly free some space in /var when it's
just become full, without needing to decide what to delete. Okay, in
practice this does not matter much because resizing the LVM and resizing
the FS is also a matter of seconds only.

	Wonko