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<p>I would estimate you are bounded by memory bandwidth (GB/sec - so
not much, but proportional to memory size) and disk bandwidth. So,
using SSD will help for certain vs spinning. I'm not sure about
the catch-22 implicit with using a ramdisk, but since the ramdisk
should be previsioned from the host to the guest, it seems like it
should work.</p>
<p>There may be other bottlenecks in drivers, etc. Not in my
knowledge domain.<br>
</p>
<br>
<div class="moz-cite-prefix">On 9/19/2017 12:53 PM, Jackson, Gary L.
wrote:<br>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks! The vanilla snapshot-create-as and
revert commands work just exactly the way I’d want them to.
I’d gotten a bit confused by the documentation and went down a
rabbit hole with external snapshots.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there any way to make the snapshot and
restore faster, like maybe by a decimal order of magnitude?
For example, will PXE booting the VM and running it entirely
off of a RAM disk and also using a RAM disk for the backing
store help?<o:p></o:p></p>
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<p class="MsoNormal"><span
style="font-size:10.5pt;color:black">-- <o:p></o:p></span></p>
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<div>
<p class="MsoNormal"><span
style="font-size:10.5pt;color:black">Gary Jackson</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span
style="font-size:12.0pt;color:black">From: </span></b><span
style="font-size:12.0pt;color:black">Doug Hughes
<a class="moz-txt-link-rfc2396E" href="mailto:doug.hughes@keystonenap.com"><doug.hughes@keystonenap.com></a><br>
<b>Date: </b>Tuesday, September 19, 2017 at 11:25 AM<br>
<b>To: </b>"Jackson, Gary L."
<a class="moz-txt-link-rfc2396E" href="mailto:Gary.Jackson@jhuapl.edu"><Gary.Jackson@jhuapl.edu></a>,
<a class="moz-txt-link-rfc2396E" href="mailto:libvirt-users@redhat.com">"libvirt-users@redhat.com"</a>
<a class="moz-txt-link-rfc2396E" href="mailto:libvirt-users@redhat.com"><libvirt-users@redhat.com></a><br>
<b>Subject: </b>Re: [libvirt-users] Rollback to running
VM<o:p></o:p></span></p>
</div>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">According to
this page: <a href="https://wiki.libvirt.org/page/Snapshots"
moz-do-not-send="true">
https://wiki.libvirt.org/page/Snapshots</a><br>
It saves complete memory state, or crash-consistent disk
state, but not both.<br>
<br>
You probably want to test it thoroughly and see how it does.
I only use the disk-consistent snapshots.<o:p></o:p></p>
<div>
<p class="MsoNormal">On 9/19/2017 11:17 AM, Jackson, Gary L.
wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<pre>Will snapshot-revert restore the processor and memory state of the VM as it was at the time of the snapshot?<o:p></o:p></pre>
<pre><o:p> </o:p></pre>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Doug Hughes<br>
Keystone NAP<br>
Fairless Hills, PA<br>
1.844.KEYBLOCK (539.2562)<o:p></o:p></p>
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<p class="MsoNormal"><img id="_x0000_i1025"
src="cid:part2.B4097F91.B26C1A02@keystonenap.com"
class="" height="110" width="185" border="0"><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<br>
<div class="moz-signature">-- <br>
<table>
<tbody>
<tr>
<td style="padding-left: 20px" width="90%">Doug Hughes<br>
Keystone NAP<br>
Fairless Hills, PA<br>
1.844.KEYBLOCK (539.2562)</td>
<td style="align: right;padding-right: 20px"><img
src="cid:part3.E128A06D.11D06AEA@keystonenap.com">
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