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Date: Thu, 24 Feb 2011 00:40:21 +0000
From: Jonathan Tripathy <jonnyt@abpni.co.uk>
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Subject: Re: [linux-lvm] Snapshots and disk re-use
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On 24/02/11 00:37, Jonathan Tripathy wrote:
>
> On 24/02/11 00:32, Stuart D. Gathman wrote:
>> On Thu, 24 Feb 2011, Jonathan Tripathy wrote:
>>
>>> So I'm guessing then, that when a snapshot is created for an origin, 
>>> then
>>> there are 2 physical copies of the data on disk? (Albeit only one is
>>> accessible at the regular filesystem level)
>> NO, NO, NO.  There is still only *one* physical copy of the data
>> after creating a snapshot.  You have simply created a "branch point"
>> which can now diverge as each branch is written to.
>>
> Then why was it suggested that I should zero my new customer LVs upon 
> creation? Please remember that my snapshots will not be written to
>
However the origin will be written to as it will be in use...