[libvirt] [PATCH 2/2] Reload snapshots on SIGHUP

[Eric Blake]

On 08/30/2011 08:59 AM, Philipp Hahn wrote:
> On receiving SIGHUP, libvirtd currently only reloads all persistent
> configs for qemu domains, but fails to reload the associated snapshot
> data.
>
> Copy code from qemudStartup() to qemudReload() to iterate over all
> domains and call qemuDomainSnapshotLoad() for every domain.
>
> Signed-off-by: Philipp Hahn<hahn at univention.de>
> ---

Are you sure this is still relevant?  In my testing, after this was 
applied, I got lots of errors:

10:58:09.987: 15794: error : virDomainSnapshotAssignDef:11113 : internal 
error unexpected domain snapshot 1308171632 already exists

and without the patch, it looked to me like the snapshots were still all 
present in memory across SIGHUP without reloading them from disk.  I 
have to wonder if commit 6766ff10d made the difference in how things are 
behaving?  Perhaps your patch is still needed, but if so, can you give 
me the test scenario you used that shows the difference in behavior pre- 
and post-patch?

Were you hand-modifying the contents of 
/var/lib/libvirt/qemu/snapshot/dom/*.xml behind libvirt's back and 
expecting the SIGHUP to have libvirt incorporate the new xml contents 
from the disk?  Are you missing a step that nukes all existing snapshot 
data in memory before re-reading snapshot data from the disk?

-- 
Eric Blake   eblake at redhat.com    +1-801-349-2682
Libvirt virtualization library http://libvirt.org