Re: Other strange things

[Ryusuke Konishi <ryusuke-sG5X7nlA6pw@public.gmane.org>]

Hi,

On Fri, 2008-01-25 at 12:46 +0100, Gergely Gábor wrote:
> On Thu, 17 Jan 2008 20:10:46 +0100
> Gergely Gábor <elentirmo.gilgalad-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> 
> Hello!
> 
> I have made a massuve uptime of 4 days by now, altough i didn't 
> run rtorrent. yesterday (early today) i noticed that the garbage
> collector might have not honoured the 3 day protection interval,
> but i'm not sure... if it will be repeated, I'll send you lots 
> of logs.
> 
> So, tried to start rtorrent now, dut it instantly quit, and the 
> console was flooded with nice traces and stuff... I attach a 
> slabinfo and a kern.log. They are big, so i bzip them.
> 
> ... one other idea. i save this letter now, and sent it after 
> a restart, with some status report then...
> 
> rtorrent escapes during the hash check... so it is a filesystem
> corruption or similiar. too bad there is no fsck yet. well, I 
> make a snapshot, and delete the affected files, and see if the
> problem arises even after that.
> 
> Best regards:


That's too bad.
But thanks for reporting the problem.

Your report told us that NILFS still has a potential BUG which may
lead to an FS-corruption.

Unfortunately, the BUG point printed in your log was a very general
one in a common b-tree lookup routine, so it's hard to identify
the cause from that.

There are many possibilities.  In the worst case, the cleaner may
degenerate the corruption.

So, I recommend you to make backups of the current mount and 
important snapshots while you can.
It should be done through ro-mounts or with -i mount option 
for a rw-mount to turn off the cleaner (see example below).

 # mount -t nilfs2 -i /dev/xxx /mount-point

Though removal of broken files may remedy the problem,
it also has a possibility to mark blocks terminated which is still
in use.  In the latter case, the cleaner might reclaim the in-use
blocks wrongly.

Sorry for not supporting fsck.
At least for the present, please make do with means of backup or 
others.

Best regards.
-- 
Ryusuke Konishi
NILFS team NTT
http://www.nilfs.org/