Re: [PATCH 3/4] XFS: Return case-insensitive match for dentry cache

["Barry Naujok" <bnaujok@xxxxxxx>]

On Fri, 16 May 2008 00:11:21 +1000, Christoph Hellwig <hch@xxxxxxxxxxxxx>  
wrote:
> On Thu, May 15, 2008 at 02:43:44PM +0100, Anton Altaparmakov wrote:
> > Yes, and you can get the performance back if you allow negative  
> > dentries to
> > be created.  You just have to make sure that every time a directory  
> > entry
> > is created in directory X, all negative dentries which are children of
> > directory X are thrown away.
> We might even be able to optimize this a little by calling d_compare on
> each alias to see if it hashes down to the same one down in the fs.
So, I gather from this comment is that the CI FS implementation overrides
d_compare but not d_hash, and the CI purge function will behave differently
if d_compare is overridden or not? If overridden, use it as per your
suggestion and if not (due to oversight or unexpected problems), purge
all negative children?

Barry.