From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: poor thin performance, relative to thick
Date: Fri, 15 Jul 2016 14:59:07 -0400
Message-ID: <20160715185906.GA29580@redhat.com>
References: <20160711204454.GA24378@helmut> <20160712184625.GA3691@redhat.com>
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To: Jon Bernard <jbernard@tuxion.com>
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On Thu, Jul 14 2016 at 12:21am -0400,
Jon Bernard <jbernard@tuxion.com> wrote:
 
> Do you have any intuition on where to start looking?

Joe asked me a very basic/obvious question: is block zeroing enabled?
(block zeroing is enabled by default -- you have to know to disable it)

If zeroing wasn't disabled that could explain some of the sizable
performance differences.  Please use/test the 'skip_block_zeroing'
feature if you aren't already (also see the "Zeroing' section of the
'lvmthin' manpage).

Mike