Date: Wed, 8 Apr 2026 14:09:48 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Alexander Lakhin <exclusion@gmail.com>,
	Sami Imseih <samimseih@gmail.com>,
	Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
	Robert Treat <rob@xzilla.net>, satyanarlapuram@gmail.com,
	pgsql-hackers <pgsql-hackers@postgresql.org>, tndrwang@gmail.com
Subject: Re: Add pg_stat_autovacuum_priority
Message-ID: <adan_E0o69p81lIj@nathan>
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On Wed, Apr 08, 2026 at 02:53:20PM -0400, Tom Lane wrote:
> Oh.  I'm not happy that any part of autovacuum.c is now reachable from
> SQL: that's the sort of modularity violation that will bite us on the
> ass (indeed just did).  Aside from this problem, the elog's that
> relation_needs_vacanalyze emits seem 100% inappropriate and misleading
> when it's being called from the view.

FWIW that elog() shouldn't be emitting anything from the view, unless
something is broken.

> I think perhaps the right way forward is to rethink the API
> guarantees for pgstat_fetch_stat_tabentry_ext, as I speculated
> about in 02502c1bc:
>
> [...]
> 
> 2. Add a "bool *should_free" parameter, like we have in tuplestores
> and some other places.  It's on the caller to pfree if should_free
> gets set, but since we'd have to touch every caller, we'd not miss
> any.

This sounds most similar to the "bool *may_free" idea that Andres just
posted.  IIUC the idea is that callers can free the result if they want,
but they aren't required to do so.

-- 
nathan