Feedback-ID: ia2694551:Fastmail
Date: Mon, 20 Apr 2026 13:45:35 +0200
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Antonin Houska <ah@cybertec.at>
Cc: Justin Pryzby <pryzby@telsasoft.com>,
	Mihail Nikalayeu <mihailnikalayeu@gmail.com>,
 Andres Freund <andres@anarazel.de>,
	Amit Kapila <amit.kapila16@gmail.com>,
 Srinath Reddy Sadipiralla <srinath2133@gmail.com>,
	Matthias van de Meent <boekewurm+postgres@gmail.com>,
 pgsql-hackers@lists.postgresql.org,
	Robert Treat <rob@xzilla.net>
Subject: Re: Adding REPACK [concurrently]
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On 2026-Apr-20, Antonin Houska wrote:

> Antonin Houska <ah@cybertec.at> wrote:
> 
> > It was discussed earlier [1] and the concerns about possibly excessive
> > resource consumptions were addressed by [2]. So I think it the fix was just
> > forgotten. Attached here.
> 
> Sorry, I attached wrong patch. This is what I meant.

Yeah, I had also written the same patch a couple of days ago.

BTW I ran into a small problem after adding some tests in cluster.sql
that would exercise this -- that test would die more or less randomly
but frequently in CI (which it never did in my laptop) because of the
size of the snapshot,

 ALTER TABLE ptnowner1 REPLICA IDENTITY USING INDEX ptnowner1_i_key;
 REPACK (CONCURRENTLY) ptnowner1;
+ERROR:  initial slot snapshot too large
+CONTEXT:  REPACK decoding worker
 RESET SESSION AUTHORIZATION;

I think the solution for this is to move cluster to a separate parallel
test.  The one where it is now is a bit too crowded.  Maybe the one for
compression is okay?  I'll test and push if I see it passing CI.


Another obvious thing after adding tests is that the LOGIN privilege is
required, which is also quite bogus IMO.  0002 here should solve that.

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/
"If you want to have good ideas, you must have many ideas.  Most of them
will be wrong, and what you have to learn is which ones to throw away."
                                                         (Linus Pauling)

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