I have tracked it a bit more using the git code of bind9 under
https://gitlab.isc.org/isc-projects/bind9. It seems that in the v9_16_22
branch the problem started to happen with this commit:
* commit ef1d909fa96479e6c4832e2e76f3ce3912cab930
| Author: Evan Hunt <e...@isc.org>
| Date: Wed May 12 17:17:05 2021 -0700
|
| backport of netmgr/taskmgr to 9.16
|
| this rolls up numerous changes that have been applied to the
| main branch, including moving isc_task operations into the
| netmgr event loops, and other general stabilization.
Just in case this is useful...
