Re: Injection points: some tools to wait and wake

Hi,

On Mon, Mar 04, 2024 at 10:44:34AM +0900, Michael Paquier wrote:
> On Fri, Mar 01, 2024 at 06:52:45AM +0000, Bertrand Drouvot wrote:
> > + if (defined($backend_type))
> > + {
> > + $backend_type = qq('$backend_type');
> > + $die_message = "the backend type $backend_type";
> > + }
> > + else
> > + {
> > + $backend_type = 'backend_type';
> > + $die_message = 'one backend';
> > +
> > + }
> > +
> > + $self->poll_query_until(
> > + 'postgres', qq[
> > + SELECT count(*) > 0 FROM pg_stat_activity
> > + WHERE backend_type = $backend_type AND wait_event = '$injection_name'
> > + ])
> > + or die
> > + qq(timed out waiting for $die_message to wait for the injection point '$injection_name');
>
> I was looking at that, and found v3 to be an overkill. First, I think
> that we should encourage callers to pass down a backend_type. Perhaps
> I am wrong to assume so, but that's based on my catalog of tests
> waiting in my stack.

Works for me.

> A second thing is that this is entirely unrelated to injection points,
> because a test may want to wait for a given wait_event on a
> backend_type without using the module injection_points. At the end, I
> have renamed the routine to wait_for_event(),

Good idea, fully makes sense.

> tweaked a bit its
> internals, and the result looked fine so I have applied it

Thanks!

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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