Re: Restart pg_usleep when interrupted

Hi,

On Tue, Aug 13, 2024 at 11:40:27AM -0500, Nathan Bossart wrote:
> On Tue, Aug 13, 2024 at 11:07:46AM -0500, Imseih (AWS), Sami wrote:
> > Having to add special handling to space out instrumentation
> > directly in vacuum_delay_point seems very odd to me. I don't
> > think vacuum_delay_point should have to worry about this.
> >
> > Also,
> > 1/ what is an appropriate interval to collect these stats?
> > 2/ What if there are other callers in the future that wish
> > to instrument parallel vacuum workers? they will need to implement
> > similar logic.
>
> None of this seems intractable to me. 1 Hz seems like an entirely
> reasonable place to start, and it is very easy to change (or to even make
> configurable). pg_stat_progress_vacuum might show slightly old values in
> this column, but that should be easy enough to explain in the docs if we
> are really concerned about it. If other callers want to do something
> similar, maybe we should add a more generic implementation in
> backend_progress.c.
>

As it looks like we have a consensus that reducing the number of interrupts also
makes sense, I just provided a rebase version of the 1 Hz version (see [0], that
also makes clear in the doc that the new field might show slightly old values).

[0]: https://www.postgresql.org/message-id/ZsSQnS9OW9EWSOk4%40ip-10-97-1-34.eu-west-3.compute.internal

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com