Re: pg_terminate_backend can terminate background workers and autovacuum launchers

Yugo Nagata wrote:

> However, we can terminate background workers by pg_terminate_backend.
> In the following example, I terminated the logical replication launcher,
> and this process did not appear again[1].
>
> postgres=# select pg_terminate_backend(30902);
> pg_terminate_backend
> ----------------------
> t
> (1 row)

I think failing to restart the replication launcher after it stops is
probably a bug, and should be fixed by having postmaster start another
one if it dies.

> Similarly, we can terminate autovacuum launcher by pg_terminate_backend,
> but a new process is restarted by postmaster in this case.[2]

Yeah, this is operating as intended. You can turn autovacuum off and
the launcher should go away, and turn it back on and launcher should
start. So we expect the autovac launcher to respond to signals.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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