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Date: Thu, 3 Mar 2016 11:02:44 +0100
From: David Sterba <dsterba@suse.cz>
To: Qu Wenruo <quwenruo@cn.fujitsu.com>
Cc: Hugo Mills <hugo@carfax.org.uk>, sri <toyours_sridhar@yahoo.co.in>,
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Subject: Re: how many chunk trees and extent trees present
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On Fri, Feb 26, 2016 at 09:29:29AM +0800, Qu Wenruo wrote:
> 
> 
> David Sterba wrote on 2015/04/17 19:29 +0200:
> > On Fri, Apr 17, 2015 at 09:19:11AM +0000, Hugo Mills wrote:
> >>> In, some article i read that future there will be more chunk tree/ extent
> >>> tree for single btrfs. Is this true.
> >>
> >>     I recall, many moons ago, Chris saying that there probably wouldn't
> >> be.
> >
> > More extent trees tied to a set of fs trees/subvolumes would be very
> > useful for certain usecases *cough*encryption*cough*.
> 
> BTW, will such design makes reflink between different set of extents 
> fallback to normal copy?

Yes, the actual reflink will not be possible.

> And I'm pretty sure that inband dedup will be affected too...

Yes.