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From: Amit Kapila <amit.kapila16@gmail.com>
Date: Sun, 10 May 2026 16:54:29 +0530
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Subject: Re: Adding REPACK [concurrently]
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
Cc: Antonin Houska <ah@cybertec.at>,
 Mihail Nikalayeu <mihailnikalayeu@gmail.com>,
	Andres Freund <andres@anarazel.de>,
 Srinath Reddy Sadipiralla <srinath2133@gmail.com>,
	Matthias van de Meent <boekewurm+postgres@gmail.com>,
	Pg Hackers <pgsql-hackers@lists.postgresql.org>,
 Robert Treat <rob@xzilla.net>
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On Fri, May 8, 2026 at 7:28=E2=80=AFPM Alvaro Herrera <alvherre@alvh.no-ip.=
org> wrote:
>
> On 2026-May-08, Amit Kapila wrote:
>
> > Some issues/inefficiencies regarding this fix and base code related to
> > db-specific snapshots built during decoding: [...]
>
> Thanks for spending time reviewing this code.  I think none of these
> problems are fundamental in nature, but they are obviously worth
> addressing for 19.  If we hit some roadblock, we can still revert only
> db-specific snapshots.
>

IIUC, the emails by Andres [1][2] on db-specific snapshots sound like
concerns which are fundamental in nature. Apart from that as well, I
think the first point mentioned in my email [3] should be at least
addressed as that causes additional WAL even after reaching
consistent_state for each runing_xact record for a db-specific
decoder.

[1] - https://www.postgresql.org/message-id/cdgw4sbbfcgk6du3iv54r2dgiy4tfyw=
oklbotlmj4irxavdcr3%40glxfw5jj277q
[2] - https://www.postgresql.org/message-id/pveffyxhnuurhb44uzqlwo3rkyzorkf=
h2rot7uwzlf2axhfvbp%407nrs2omysxkc
[3] - https://www.postgresql.org/message-id/CAA4eK1LygCDP3FiFzXY9iVNFcHxhf7=
TT_DFf7tryTu2oipmfpA%40mail.gmail.com

--=20
With Regards,
Amit Kapila.