Re: Exposing the lock manager's WaitForLockers() to SQL

Hi,

On 2023-01-10 10:01:25 +0100, Marco Slot wrote:
> On Fri, Dec 23, 2022 at 11:43 AM Will Mortensen <will@extrahop.com> wrote:
> > We'd like to be able to call the lock manager's WaitForLockers() and
> > WaitForLockersMultiple() from SQL. Below I describe our use case, but
> > basically I'm wondering if this:
> >
> >     1. Seems like a reasonable thing to do
> >
> >     2. Would be of interest upstream
> >
> >     3. Should be done with a new pg_foo() function (taking an
> >        oid?), or a whole new SQL command, or something else
> 
> Definitely +1 on adding a function/syntax to wait for lockers without
> actually taking a lock.

I think such a function would still have to integrate enough with the lock
manager infrastructure to participate in the deadlock detector. Otherwise I
think you'd trivially end up with loads of deadlocks.

Greetings,

Andres Freund