Message-ID: <1a236172c7dda72939e4293657a90536cce7dd16.camel@j-davis.com>
Subject: Re: Adding locks statistics
From: Jeff Davis <pgsql@j-davis.com>
To: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>, Michael Paquier
	 <michael@paquier.xyz>
Cc: Greg Sabino Mullane <htamfids@gmail.com>,
	pgsql-hackers@lists.postgresql.org
Date: Tue, 12 Aug 2025 08:42:48 -0700
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On Tue, 2025-08-12 at 09:37 +0000, Bertrand Drouvot wrote:
> It can be used for example for:
>=20
> 1. checking if "waits" is close to "requests". Then it means you
> usually have to
> wait before acquiring the lock, which means you may have a
> concurrency issue.
>=20
> 2. lock_timeout and deadlock_timeout tuning (lock_timeout is visible
> only in the
> logs if log_min_error_statement is set appropriately).
>=20
> 3. checking the "requests"/"fastpath" ratio to see if
> "max_locks_per_transaction"
> needs tuning (see c4d5cb71d2).
> "
>=20
> Do these seem like useful use cases?

Those seem plausibly useful, but I don't recall needing that exact
information myself, and I wanted to hear more from others.

For instance, a view could be helpful to diagnose concurrency issues,
but I think that's worth discussing in more detail to see what kinds of
issues it can help with and how it complements other approaches. I
suspect when we get into the details, different people (or different
situations) would want slightly different information out of that view.

Regards,
	Jeff Davis