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Why clearing the VM doesn't require registering vm buffer in wal record

Melanie Plageman <melanieplageman@gmail.com>

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From: Melanie Plageman <melanieplageman@gmail.com>
To: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Cc: Robert Haas <robertmhaas@gmail.com>, Heikki Linnakangas <hlinnaka@iki.fi>, Andres Freund <andres@anarazel.de>
Date: 2026-03-05T19:56:13Z
Lists: pgsql-hackers 
Today Andres and I noticed that heap_{update,insert,delete}() don't
register the VM buffer when they are clearing the VM. I was under the
impression that any buffers modified needed to be registered in the
WAL record. Without which, you'll never do an FPI. It seems like this
could cause checksum failures. What are we missing?

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Revamp the WAL record format.

  2. Allow I/O reliability checks using 16-bit checksums

  3. Make the visibility map crash-safe.