Hello Sandino,
"Sandino Flores Moreno":
> I'm using aufs to rapidly create file systems for embedded devices, and
> after creating the new file systems, but before doing any other thing, a
> file and directory are always created inside the changes_dir
>
> .wh..wh.aufs
> .wh..wh.plink/
>
> I'm mounting with noplink option and using aufs 20070402 with kernel vanilla
> 2.6.20.4
>
> What are they for?
> Is it possible to avoid them?
.wh..wh.aufs is the source of all whiteouts.
When your branch is marked as '=rw', it will be always created.
(from the aufs manual)
All whiteouts are hardlinked, including '<writable branch top
dir>/.wh..wh.aufs.'
The hardlink on an ordinary (disk based) filesystem does not consume
inode resource newly. But in linux tmpfs, the number of free inodes
will be decremented by link(2). It is recommended to specify nr_inodes
option to your tmpfs if you meet ENOSPC. Use this option after checking
by 'df -i'.
> The options I'm using look like this:
>
> rw,dirs=changes_dir=rw:master_dir=ro,xino=/tmp/xino,noplink
You can avoid .wh..wh.plink, if you write 'noplink' before 'dirs='.
The mount options are interpreted from left to right basically. It
is described in the aufs manual.
But I have a plan to change this rule a little bit.
- at remount-time, the options are interpreted from left to right
- at mount-time, br: or dirs= is interpreted last. this new rule will
not confuse you.
Junjiro Okajima
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
