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Subject: Re: Is btrfs-convert able to deal with sparse files in a ext4
 filesystem?
To: linux-btrfs@vger.kernel.org
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From: Andrei Borzenkov <arvidjaar@gmail.com>
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Date: Sun, 2 Apr 2017 09:30:46 +0300
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02.04.2017 03:59, Duncan пишет:
> 
> 4) In fact, since an in-place convert is almost certainly going to take 
> more time than a blow-away and restore from backup,

This caught my eyes. Why? In-place convert just needs to recreate
metadata. If you have multi-terabyte worth of data copying them twice
hardly can be faster.