After further investigation, I figured out that when issuing a savevm command
the entire qemu process gets stuck on IO wait.
I can't issue any other commands on the monitor the process is shown as D and the guest is in softlockup state.
Looking at the way migrate (and the -d for detach I presume) is working I suppose the same behaviour would be expected from the savevm function.
A savevm -d so that the qemu process would not be freezed while saving the data.
Sorry if I am just talking non sense but my snapshot on iscsi storage takes about 1 minutes.
which means that my guest are down for a minute or so which is not ideal.
Thanks for your time
-------- Message initial -------- De: Benjamin Cleyet-Marrel <address@hidden> À: address@hidden Sujet: [Qemu-devel] Qemu savevm and CPU soft lockup Date: Fri, 18 Sep 2009 11:56:41 +0200
First post to this list so sorry if I am mistaken.
I am using qemu-kvm-0.11.0-rc2 I've googled quite a lot and could not find anyone having or reporting the same problem.
The guest is a Centos5.3
The savevm/loadvm seems to be broken:
When issuing a savevm in the monitor,
Guest get stuck for a few seconds and I get the infamous soft lockup a couple of time. (see bellow)
In the end, the snapshot is working.
When doing a loadvm I often get weird behaviour on the console.
this can be completly removed if I issue a stop and cont before and after the loadvm.
Am I doing something wrong or is this a bug ?