Re: Let's invent a function to report lock-wait-blocking PIDs

Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
>> pg_is_lock_exclusive(lock, lock) returns boolean
>> pg_is_lock_exclusive(lock[], lock[]) returns boolean
>
>> I suppose that the lock type would be text ('ExclusiveLock'), but we
>> could also expose a new ENUM type for that (pg_lock_mode).
>
> I don't have an objection to providing such a function, but it doesn't
> do anything for the problem beyond allowing getting rid of the hairy
> case expression. That's a good thing to do of course --- but what about
> the indirect-blockage issue?

It's too late for my brain to build the full answer, the idea is that we
have another way to build the dependency cycles in the pg_locks query
and then we can aggregate locks at each level and see about conflicts
once we accumulated the data.

Is that even possible? E_GOTOSLEEP.

Regards,
--
Dimitri Fontaine
http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support