On Tue, 27 Feb 2024 at 01:22, Kirill Reshke <reshkekir...@gmail.com> wrote:
> > > On Mon, 26 Feb 2024 at 20:10, Nathan Bossart <nathandboss...@gmail.com> > wrote: > >> On Mon, Feb 26, 2024 at 12:38:40PM +0500, Kirill Reshke wrote: >> > I see 2 possible ways to implement this. The first one is to have hool >> in >> > pg_signal_backend, and define a hook in extension which can do the >> thing. >> > The second one is to have a predefined role. Something like a >> > `pg_signal_autovacuum` role which can signal running autovac to cancel. >> But >> > I don't see how we can handle specific `application_name` with this >> > solution. >> >> pg_signal_autovacuum seems useful given commit 3a9b18b. >> >> -- >> Nathan Bossart >> Amazon Web Services: https://aws.amazon.com > > > Thank you for your response. > Please find a patch attached. > > In patch, pg_signal_autovacuum role with oid 6312 added. I grabbed oid > from unused_oids script output. > Also, tap tests for functionality added. I'm not sure where to place them, > so I placed them in a separate directory in `src/test/` > Seems that regression tests for this feature are not possible, am i right? > Also, I was thinking of pg_signal_autovacuum vs pg_signal_backend. > Should pg_signal_autovacuum have power of pg_signal_backend (implicity)? > Or should this role have such little scope... > > Have a little thought on this, will share. Do we need to test the pg_cancel_backend vs autovacuum case at all? I think we do. Would it be better to split work into 2 patches: first one with tests against current logic, and second one with some changes/enhancements which allows to cancel running autovac to non-superuser (via `pg_signal_autovacuum` role or some other mechanism)?