Comment 4 for bug 2060931

We are also seeing quite common, but probably not the same issue with Nova, with slightly different stack trace, but same result:
https://paste.openstack.org/show/b3sOW4WSg74s3qk5vCgB/

It also can be the same issue, just logs from compute rather then API side.

Though, from what we have tested - heartbeat_in_pthread: False for Nova API seems to improve things with this one.

We're still monitoring state and it's probably early to make final conclusions. But I kinda do see how that can be related.

As eventlet import in oslo.messaging happens only for enabled heartbeat_in_pthread, and was introduced with this option:
https://github.com/openstack/oslo.messaging/commit/22f240b82fffbd62be8568a7d0d3369134596ace

So disabling usage of eventlet seems to help in our case.