Description of problem: VDSM stats collection and reporting is moving out to collectd. MoM should do the same instead of keeping the dependency on VDSM stats otherwise we will forever keep hugh redundant amount of data. Ovirt engine itself is going to move to other sources of stats and will minimize the use of VDSM stats and eventually this structure should decrease in size and order to clean it mom should move to collectd. For example, engine does not use majflt and pageflt. it is just there in the stats. And if engine doesn't use it, neither do dwh. MoM is the only component needing it and collectd is a perfect interface to get these kinds of data. If VDSM is going to have a python collectd module to collect stats, then it should be reusable, so mom could just use the module as a replacement for all the getStats call. That would be also very efficient.
Nothing from the description is currently viable and worth the risk of breaking the existing solution. We can reconsider if we ever decide to rewrite MOM.