[Lustre-discuss] trying to BRW to non-existent file xyz

[Bernd Schubert]

On Monday 26 November 2007 18:33:02 you wrote:
> Hello!
>
> On Nov 26, 2007, at 12:08 PM, Bernd Schubert wrote:
> > when an OST reports "trying to BRW to non-existent file xyz", how
> > can I find
> > out which file the inode xyz belongs to?
>
> Usually there is none. Can you tell us more about situations where you
> see this?
> Were there any evictions?

I think so, this message just happened on a rather fresh customer system and 
is rather annoying, since it fills the logs...
I can reproduce this rather soon here, I just need to run fsstress for some 
hours. After some time there are evictions.

> One common scenario for this kind of errors is this:
> Client opens a file. File gets unlinked. Client is evicted from mds,
> mds notices
> it held last reference to a file and issue destroy request for file
> objects (effectively
> removing file objects on OSTs).
> Now if client would continue to access the file (because it was not
> evicted from ost
> or if it reconnected), you will get these errors.
>
> You can do e.g. lfs find /mountpoint -v for your fs (which I guess
> would take quite a
> while if it's big) and then grep the output for interesting objectid
> (just pay
> attention that ost index should also match).

Thanks, I will try over night, don't want to disturb the people there now.



Thanks a lot,
Bernd

-- 
Bernd Schubert
Q-Leap Networks GmbH