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Date: Fri, 3 Jun 2016 08:54:15 +1000
From: Dave Chinner <david@fromorbit.com>
Subject: Re: [RFC] allow enabling reflinks at runtime
Message-ID: <20160602225415.GP12670@dastard>
References: <1464877150-20457-1-git-send-email-hch@lst.de>
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To: Christoph Hellwig <hch@lst.de>
Cc: xfs@oss.sgi.com, darrick.wong@oracle.com

On Thu, Jun 02, 2016 at 04:19:07PM +0200, Christoph Hellwig wrote:
> I've had some vocal user requests to allow enabling reflinks at run time,
> which happens to be a mostly trivial feature.  The only caveat is that we
> need a large enough log size to support the reflink requirements, but for
> typical large file systems that's not an issue.

Hmmm - how does this interact with all the rmap code? I was not
planning on enabling reflink without rmap and vice versa simply
because it makes the validation and testing matrix vastly more
complex. Indeed, having reflink turned on after a filesystem has
aged for some time (i.e. from unknown initial conditions) makes
validation especially tricky....

Darrick?

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

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