Automatic fsck

[Colin Ian King]

On Tue, 2008-08-12 at 11:15 +0100, Matt Zimmerman wrote:
> On Mon, Aug 11, 2008 at 02:09:19PM -0700, Bryce Harrington wrote:
> > On Mon, Aug 11, 2008 at 11:52:25AM +0100, Matt Zimmerman wrote:
> > > == Filesystem checking / AutoFsck ==
> > > 
> > > A suggestion was made to the technical board that Ubuntu could be smarter
> > > about how and when it performs filesystem integrity checks (fsck).
> > > 
> > > Decision: This should be discussed more widely in the developer community
> > > Action: Scott to start a thread on ubuntu-devel/-discuss
> > 
> > I find the autofsck to be most notable on my laptop, perhaps because I
> > reboot it more frequently, and because it usually chooses to autofsck at
> > some inopportune time.  I don't know if laptop harddrives need fsck more
> > than desktop's, but I wouldn't mind seeing the frequency be reduced for
> > laptops.
> > 
> > Alternatively, maybe the autofsck could be made to take a few more
> > factors into account, such as total run time since last fsck, total
> > absolute time since last fsck, drive age, etc.
> 
> Total run time sounds like an interesting one to watch.

I suspect fsck times are going to be less of an issue for systems using
ext4 in the (hopefully not so distant) future - ext4 is significantly
faster to fsck than ext3 (from my understanding, ext3 fsck times are
linearly proportional to the number of inodes, ext4 doesn't seem to be).

See the table in
http://thunk.org/tytso/blog/2008/08/08/fast-ext4-fsck-times/

Mind you, there are some large disks out there nowadays...

Colin K.

> 
> Some of the other ideas which have been proposed are:
> 
> Run fsck during shutdown (when the user isn't expecting to be able to use
> the system for a while anyway) rather than at startup.
> https://blueprints.launchpad.net/ubuntu/+spec/prompt-for-fsck-on-shutdown
> 
> Allow fsck to be easily skipped.  This was implemented in 8.04 as part of
> https://blueprints.launchpad.net/ubuntu/+spec/usplash-polish
> 
> Skip fsck when running on battery.  Also implemented in 8.04 as part of
> https://blueprints.launchpad.net/ubuntu/+spec/usplash-polish
> 
> -- 
>  - mdz
>