We have been planning switching from minidom to etree in Vdsm for long time. There are several good reasons why to make the change: - We currently use both minidom and etree, we should use a single library. - etree has apparently better performance in the sense of CPU time and RAM usage. - etree has a simpler and more convenient API (e.g. limited XPath support). After various discussions and trying different draft approaches, there is now available a complete series of patches migrating virt usage of minidom to etree. It starts with patch https://gerrit.ovirt.org/55769 and you can follow the whole vm-etree topic from there. Please read the commit message in the initial patch, it explains the overall approach. I tried to make the series reviewer friendly, for patch-by-patch review. It's still draft, not finished, missing many tests, etc., but it already basically works. If you have any serious problems with the approach to the conversion or its general directions, tell me before we start discussing details. Just don't forget we must perform the conversion in some reasonably safe way and it must be possible to review it. Please note the series doesn't try to solve all the world/Vdsm problems, it focuses just on the etree conversion. Further changes may be implemented in followup patches. I already implemented some post-refactoring in vm-etree-refact topic starting with https://gerrit.ovirt.org/60940. Thanks to Francesco Romani for cooperation and help with the work.