Re: inode leak in 2.6.24?

[David Chinner <dgc@sgi.com>]

On Wed, Feb 20, 2008 at 03:36:53PM +0100, Ferenc Wagner wrote:
> David Chinner <dgc@sgi.com> writes:
> > The xfs inodes are clearly pinned by the dentry cache, so the issue
> > is dentries, not inodes. What's causing dentries not to be
> > reclaimed?  I can't see anything that cold pin them (e.g. no filp's
> > that would indicate open files being responsible), so my initial
> > thoughts are that memory reclaim may have changed behaviour.
> >
> > I guess the first thing to find out is whether memory pressure
> > results in freeing the dentries. To simulate memory pressure causing
> > slab cache reclaim, can you run:
> >
> > # echo 2 > /proc/sys/vm/drop_caches
> >
> > and see if the number of dentries and inodes drops. If the number
> > goes down significantly, then we aren't leaking dentries and there's
> > been a change in memoy reclaim behaviour. If it stays the same, then
> > we probably are leaking dentries....
> 
> Hi Dave,
> 
> Thanks for looking into this.  There's no real conclusion yet: the
> simulated memory pressure sent the numbers down allright, but
> meanwhile it turned out that this is a different case: on this machine
> the increase wasn't a constant growth, but related to the daily
> updatedb job.  I'll reload the original kernel on the original
> machine, and collect the same info if the problem reappers.

Ok, let me know how it goes when you get a chance.

Cheers,

Dave.
-- 
Dave Chinner
Principal Engineer
SGI Australian Software Group