Hi,
src/backend/replication/logical/launcher.c
* Worker started and attached to our shmem. This check is safe
* because only launcher ever starts the workers, so nobody can steal
* the worker slot.
The tablesync patch enabled even worker to start another worker.
So the above assumption is not valid for now.
This issue seems to cause the corner case where the launcher picks up
the same worker slot that previously-started worker has already picked
up to start another worker.
Regards,
--
Fujii Masao