From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Chinner <david@fromorbit.com>
Subject: Re: [BULK]  Re: [PATCH RFC 0/2] skiplists for range indexes
Date: Tue, 7 May 2013 12:12:08 +1000
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Cc: Dave Chinner <dchinner@redhat.com>, Jan Kara <jack@suse.cz>,
	Linux FS Devel <linux-fsdevel@vger.kernel.org>,
	David Woodhouse <David.Woodhouse@intel.com>,
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To: Chris Mason <clmason@fusionio.com>
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On Mon, May 06, 2013 at 07:28:19AM -0400, Chris Mason wrote:
> Quoting Dave Chinner (2013-05-05 18:44:16)
> > On Sun, May 05, 2013 at 10:38:12AM -0400, Chris Mason wrote:
> > 
> > It's an rbtree per allocation group. The code is doing an exact
> > extent match and there is potential for multiple buffers at the same
> > offset (key) into the tree so we can't use a radix tree at all. See
> > _xfs_buf_find() for the rbtree search code...
> 
> The exact match part won't work with my current code.  But a small
> change will let you pick your own insertion point and allow the
> duplicates.  I'll have to break up deletion a little as well, but it is
> already setup for this.
> 
> After the merge window, I've got linuxcon japan.  Once both are done
> I'll pick this up again and see what I can do.

No worries - I'm not in any hurry to replace this code right now.
Reducing the number of unnecessary/repeated buffer lookups is
probably a bigger win for XFS right now...

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com