<div dir="auto">Hello,<div dir="auto"><br></div><div dir="auto">What's the version of the manager (engine)?</div><div dir="auto"><br></div><div dir="auto">Could you please provide the link or the SPM and the host running the VM?</div><div dir="auto"><br></div><div dir="auto">Thanks,</div><div dir="auto">Ala</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Sep 22, 2017 1:19 PM, "Troels Arvin" <<a href="mailto:troels@arvin.dk">troels@arvin.dk</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hello,<br>
<br>
I have a RHV 4.1 virtualized guest-server with a number of rather large<br>
VirtIO virtual disks attached. The virtual disks are allocated from a<br>
fibre channel (block) storage domain. The hypervisor servers run RHEL 7.4.<br>
<br>
When I take a snapshot of the guest, then it takes a long time to remove<br>
the snapshots again, when the guest is powered off (a snapshot of a 2 TiB<br>
disk takes around 3 hours to remove). However, when the guest is running,<br>
then snapshot removal is very quick (perhaps around five minutes per<br>
snapshot). The involved disks have not been written much to while they<br>
had snapshots.<br>
<br>
I would expect the opposite: I.e., when the guest is turned off, then I<br>
would assume that oVirt can handle snapshot removal in a much more<br>
aggressive fashion than when performing a live snapshot removal?<br>
<br>
When performing offline snapshot removal, then on the hypervisor having<br>
the SPM role, I see the following in output from "ps xauw":<br>
<br>
vdsm 10255 8.3 0.0 389144 27196 ? S<l 13:40 7:04 /usr/bin/qemu-img<br>
convert -p -t none -T none -f qcow2 /rhev/data-center/mnt/blockSD/<wbr>xxx/<br>
images/yyy/zzz -O raw /rhev/data-center/mnt/blockSD/<wbr>xxx/images/yyy/<br>
zzz_MERGE<br>
<br>
I don't see the same kind of process running on a guest's hypervisor when<br>
online snapshot removal is in progress.<br>
<br>
I've read most of <a href="https://www.ovirt.org/develop/release-management/
features/storage/remove-snapshot/" rel="noreferrer" target="_blank">https://www.ovirt.org/develop/<wbr>release-management/<br>
features/storage/remove-<wbr>snapshot/</a><br>
My interpretation from that document is that I should expect to see "qemu-<br>
img commit" commands instead of "qemu-img convert" processes. Or?<br>
<br>
The RHV system involved is somewhat old, having been upgrade many times<br>
from 3.x through 4.1. Could it be that it carries around old left-overs<br>
which results in obsolete snapshot removal behavior?<br>
<br>
--<br>
Regards,<br>
Troels Arvin<br>
<br>
______________________________<wbr>_________________<br>
Users mailing list<br>
<a href="mailto:Users@ovirt.org">Users@ovirt.org</a><br>
<a href="http://lists.ovirt.org/mailman/listinfo/users" rel="noreferrer" target="_blank">http://lists.ovirt.org/<wbr>mailman/listinfo/users</a><br>
</blockquote></div></div>