Re: Adding REPACK [concurrently]

Alvaro Herrera <alvherre@alvh.no-ip.org>

From: Alvaro Herrera <alvherre@alvh.no-ip.org>

To: Amit Kapila <amit.kapila16@gmail.com>

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>

Date: 2026-05-19T18:52:13Z

Lists: pgsql-hackers

On 2026-May-14, Amit Kapila wrote:

> The broader issue is that the entire logical decoding mechanism is
> designed to process cluster-wide transactions. This patch tries to
> bypass that foundational assumption, but only during the initial
> snapshot construction while processing running_xacts record.
> 
> To be clear, I am not against the idea of db-specific snapshots to
> enable concurrent repacks. My concern is simply the time required to
> get the architecture right. In its current state, we need more time to
> carefully consider how this db-specific concept interacts with the
> rest of the logical decoding machinery, which is built for
> cluster-wide records.

Hmm.  So at this point I have to admit that the time I'll have before
beta 1 is going to be very scarce.  You're probably right that it's
better to revert db-specific snapshots in pg19, and try again for 20.
The revert should be a simple patch.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/