<p dir="ltr">Yes. These two forms are backwards of each other. Lvm snapshot starts empty and fills up. VM snapshot starts full and the continued-use section begins to fill but it's the new part.</p>
<div class="gmail_quote">On Jan 23, 2016 3:09 PM, "DJ-Pfulio" <<a href="mailto:djpfulio@jdpfu.com">djpfulio@jdpfu.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Ah ... must have confused LVM snapshots with some other sort, perhaps QCOW2<br>
snapshots?<br>
<a href="http://wiki.qemu.org/Documentation/CreateSnapshot" rel="noreferrer" target="_blank">http://wiki.qemu.org/Documentation/CreateSnapshot</a> Yep. Sorry. Different<br>
use-case completely, hence the different results.<br>
<br>
<br>
<br>
On 01/23/2016 02:09 PM, Jim Kinney wrote:<br>
> The new data is written to the ORIGINAL lvm. At that point, the old data is<br>
> written to the snapshot lvm. The snapshot lvm is initially of zero real<br>
> size, no disk space is used. Only when blocks need to be written to in the<br>
> original lvm are blocks written to in the snapshot. Thus drive space used<br>
> is double the size of the new data: one write to archive the old data in<br>
> the snapshot and a second write to store the new data in the original lvm.<br>
> Its a performance hit but an overall time saver. Think of the snapshot as<br>
> nothing but hard links to physical extents until an extent changes.<br>
> On Jan 23, 2016 12:42 PM, "DJ-Pfulio" <<a href="mailto:djpfulio@jdpfu.com">djpfulio@jdpfu.com</a>> wrote:<br>
><br>
>> Concerning LVM backups.<br>
>><br>
>> If all the change data is being written to the snapshot area, how does<br>
>> that get<br>
>> merged back into the main storage and main DB after we are done with<br>
>> backups?<br>
>><br>
>><br>
>><br>
>><br>
>> On 01/22/2016 02:40 PM, Jim Kinney wrote:<br>
>>> Slide deck is live on <a href="http://ale.org" rel="noreferrer" target="_blank">ale.org</a> in meeting announcement page.<br>
>>> On Fri, 2016-01-22 at 10:54 -0500, DJ-Pfulio wrote:<br>
>>>> Are there notes, the presentation, and/or video from last night?<br>
>>>> Sounds like the presentation and some notes could really be helpful<br>
>>>> based on the<br>
>>>> comments.<br>
>>>><br>
>>>> Sorry I missed it!<br>
>> _________________________<br>
_______________________________________________<br>
Ale mailing list<br>
<a href="mailto:Ale@ale.org">Ale@ale.org</a><br>
<a href="http://mail.ale.org/mailman/listinfo/ale" rel="noreferrer" target="_blank">http://mail.ale.org/mailman/listinfo/ale</a><br>
See JOBS, ANNOUNCE and SCHOOLS lists at<br>
<a href="http://mail.ale.org/mailman/listinfo" rel="noreferrer" target="_blank">http://mail.ale.org/mailman/listinfo</a><br>
</blockquote></div>