Change in vdsm[master]: virt: dump domain xml when change is detected

Francesco Romani has uploaded a new change for review.

Change subject: virt: dump domain xml when change is detected
......................................................................

virt: dump domain xml when change is detected

The Domain XML should not change often during the lifetime of a VM.
Nevertheless, it is greatly helpful to have up-to-date information
when troubleshooting issues.

This patch logs the domain XML whenever a change is detected, to improve
the debuggability of VDSM.

Change-Id: I658ed887e258c4217a3d1eddb4924688b5a613f6
Signed-off-by: Francesco Romani 
---
M vdsm/virt/vm.py
1 file changed, 5 insertions(+), 2 deletions(-)

git pull ssh://gerrit.ovirt.org:29418/vdsm refs/changes/49/33549/1

diff --git a/vdsm/virt/vm.py b/vdsm/virt/vm.py
index ad8cb0e..e728902 100644
--- a/vdsm/virt/vm.py
+++ b/vdsm/virt/vm.py
@@ -4492,8 +4492,11 @@
         self._lastXMLDesc = self._dom.XMLDesc(0)
         devxml = _domParseStr(self._lastXMLDesc).childNodes[0]. \
             getElementsByTagName('devices')[0]
-        self._devXmlHash = hash(devxml.toxml())
-
+        xmlHash = hash(devxml.toxml())
+        if xmlHash != self._devXmlHash:
+            self.log.debug('changed device configuration:\n%s',
+                           self._lastXMLDesc)
+        self._devXmlHash = xmlHash
         return self._lastXMLDesc

def _ejectFloppy(self):

Francesco Romani has posted comments on this change.

Change subject: virt: dump domain xml when change is detected
......................................................................

Patch Set 1: Code-Review-1

let's discuss approaches before.

[Jenkins CI RO]

oVirt Jenkins CI Server has posted comments on this change.

Change subject: virt: dump domain xml when change is detected
......................................................................

Patch Set 1:

Build Failed

http://jenkins.ovirt.org/job/vdsm_master_unit_tests_gerrit_el/11744/ : SUCCESS

http://jenkins.ovirt.org/job/vdsm_master_unit-tests_created/12688/ : SUCCESS

http://jenkins.ovirt.org/job/vdsm_master_virt_functional_tests_gerrit/1701/ : There was an infra issue, please contact [e-mail]

http://jenkins.ovirt.org/job/vdsm_master_pep8_gerrit/12533/ : SUCCESS

Francesco Romani has abandoned this change.

Change subject: virt: dump domain xml when change is detected
......................................................................

Abandoned

bad idea. Better idea: per-device log when device changes, either solicited or unsolicited by VDSM.