Date: Wed, 15 Apr 2026 16:51:16 -0400
From: Bruce Momjian <bruce@momjian.us>
To: Melanie Plageman <melanieplageman@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@lists.postgresql.org>
Subject: Re: First draft of PG 19 release notes
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On Wed, Apr 15, 2026 at 01:56:50PM -0400, Melanie Plageman wrote:
> On Tue, Apr 14, 2026 at 9:19 PM Bruce Momjian <bruce@momjian.us> wrote:
> >
> > I have completed the first draft of the PG 19 release notes:
> >
> >         https://www.postgresql.org/docs/devel/release-19.html
> 
> As of b46e1e54d078def, SELECT queries may update the visibility map.
> Previously only vacuum did this. I think users may be confused by this
> if it is not mentioned in the release notes.

Yes, I puzzled on this one and I am glad you clarified its purpose.
I think it should be added, and I have applied the attached patch.

> Additionally, users may notice that there are no longer
> XLOG_HEAP2_VISIBLE records. A series of commits culminating in
> a881cc9c7e819fb (others being d96f87332b378, add323da40a6bf9e0,
> 1252a4ee2863673, a759ced2f1e) moved VM setting into the
> XLOG_HEAP2_PRUNE_VACUUM_SCAN record. Users may notice that
> XLOG_HEAP2_VISIBLE records are no longer produced.
> 
> This is more minor, but we also now (378a216187aea1) set pd_prune_xid
> on insert, so users may notice that a freshly inserted page is
> on-access pruned and then the VM is set (which wouldn't have happened
> before without vacuum).

Uh, I don't want to get into the internals too much in the release
notes, in fear of confusing/losing readers.  I think this is too
low-level to mention, but we now have a good "prune" item so if they see
big improvements, they will know why.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  Do not let urgent matters crowd out time for investment in the future.

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diff --git a/doc/src/sgml/release-19.sgml b/doc/src/sgml/release-19.sgml
index 2137621f6a6..6e038851a67 100644
--- a/doc/src/sgml/release-19.sgml
+++ b/doc/src/sgml/release-19.sgml
@@ -596,6 +596,22 @@ New server variables are io_min_workers, io_max_workers, io_worker_idle_timeout,
 </para>
 </listitem>
 
+<!--
+Author: Melanie Plageman <melanieplageman@gmail.com>
+2026-03-30 [b46e1e54d] Allow on-access pruning to set pages all-visible
+-->
+
+<listitem>
+<para>
+Allow query table scans to mark pages as all-visible in the free space map (Melanie Plageman)
+<ulink url="&commit_baseurl;b46e1e54d">&sect;</ulink>
+</para>
+
+<para>
+Previously only VACUUM and COPY FREEZE could this.
+</para>
+</listitem>
+
 <!--
 Author: Masahiko Sawada <msawada@postgresql.org>
 2026-04-06 [1ff3180ca] Allow autovacuum to use parallel vacuum workers.

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