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Date: Wed, 14 Jan 2015 09:34:20 +0100
From: Zdenek Kabelac <zkabelac@redhat.com>
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Subject: Re: [linux-lvm] determining snapshot overhead
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Dne 14.1.2015 v 08:24 Bram Klein Gunnewiek napsal(a):
> Hello,
>
> I am trying to create snapshots of thick volumes that can't break because they
> overflow (thin volumes are not an option right now). I can't find information
> on how to calculate (in advance) the metadata overhead of a snapshot when all
> blocks in the origin volume are changed (e.g. the snapshot is 100% full). Is
> there a way to do this?


Recent versions of lvm2  (let's say >= 111) are able to determine this size 
automatically - just use: 'lvcreate -s -l100%ORIGIN vg/origin'

Regards

Zdenek