Re: Adding locks statistics

Hi,

On Mon, Feb 16, 2026 at 04:00:56PM -0500, Andres Freund wrote:
> Hi,
>
> On 2026-02-16 10:10:21 +0000, Bertrand Drouvot wrote:
> > Yeah, providing the wait_time would be great. Just to be sure, are you suggesting
> > to remove all the fields (i.e requests, timeouts, deadlock_timeouts and fastpath)
> > and just add a wait_time field instead?
>
> Well, I'd maybe make it waits, wait_time and perhaps fastpath exceeded.

Okay, done that way in the attached. To avoid overhead due to timing as much as
possible, the patch simply relies on log_lock_waits and deadlock_timeout. It means
that it relies on the existing code, and increments waits and wait_time only if
log_lock_waits is on and if the session waited longer than deadlock_timeout.

I did not want to dissociate the waits and wait_time increments so that their
ratio could still make sense.

That sounds like a good compromise, thoughts?

> > I think that keeping requests would make sense to be able to get the average
> > wait time per request.
>
> I don't think I'd request for that (as that would require counting in the
> normal case), I'd use the number of waits.

Yeah, I meant to say waits and not requests.

Regards,

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