Feedback-ID: ia2694551:Fastmail
Date: Sat, 9 Aug 2025 15:33:31 +0200
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Mihail Nikalayeu <mihailnikalayeu@gmail.com>
Cc: Fujii Masao <masao.fujii@gmail.com>, Robert Treat <rob@xzilla.net>,
	Pg Hackers <pgsql-hackers@lists.postgresql.org>,
 Antonin Houska <ah@cybertec.at>
Subject: Re: Adding REPACK [concurrently]
Message-ID: <202508091333.qvgvo7ikuezm@alvherre.pgsql>
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On 2025-Aug-09, Mihail Nikalayeu wrote:

> Hello!
> 
> One more thing - I think build_new_indexes and
> index_concurrently_create_copy are very close in semantics, so it
> might be a good idea to refactor them a bit.
> 
> I’m still concerned about MVCC-related issues. For multiple
> applications, this is a dealbreaker, because in some cases correctness
> is a higher priority than availability.

Please note that Antonin already implemented this.  See his patches
here:
https://www.postgresql.org/message-id/77690.1725610115%40antos
I proposed to leave this part out initially, which is why it hasn't been
reposted.  We can review and discuss after the initial patches are in.
Because having an MVCC-safe mode has drawbacks, IMO we should make it
optional.

But you're welcome to review that part specifically if you're so
inclined, and offer feedback on it.  (I suggest to rewind back your
checked-out tree to branch master at the time that patch was posted, for
easy application.  We can deal with a rebase later.)

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/
Officer Krupke, what are we to do?
Gee, officer Krupke, Krup you! (West Side Story, "Gee, Officer Krupke")