[nova] Stein regressions
Hey cool cats,
I know we just released Stein last week so what better time to write an
email about a bunch of Stein regressions?!
I wanted to dump this in the list so (a) I don't lose track of them all
and (b) other people are aware and get involved.
In no particular order:
There is a patch being worked: https://review.openstack.org/#/c/649345/
The workaround for this would be to disable the
_heal_instance_info_cache periodic in nova-compute services that manage
baremetal nodes by setting the heal_instance_info_cache_interval value to 0.
We have a re-create scenario for this in devstack (noted in the bug
report). I've been unable to recreate in a functional test, possibly
because of how sqlite deals with NULL values in unique constraints
differently from mysql. I would have thought this regression test 
would have hit it but it didn't.
There are some options for fixing this, some more hacky than others, e.g.:
Need some input from others on fixing that bug in maybe a less hacky way.
I found this when writing  to try and recreate the previous bug
1824435. I have a series up for this starting with a recreate patch .
The fix on top is one of a few options I detailed in the bug report.
It's not pretty but it works.
The workaround for this would be to archive deleted records but you'd
have to do that after each run of the online data migration which is not
I just triaged this a couple of hours ago. I plan on writing a
functional regression recreate test since the recreate scenario seems
pretty easy - try to resize a volume-backed server where the new flavor
has a smaller disk than the old flavor. The fix should also be
Once we get fixes landed and backported to stable/stein for these bugs
we should do a patch release ASAP.