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Re: Why clearing the VM doesn't require registering vm buffer in wal record - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Why clearing the VM doesn't require registering vm buffer in wal record
Date
Msg-id CA+Tgmob8zCVDmvQe5eCy5cCaDfRZN0sJdEHL9YBz2k9-pvL9_w@mail.gmail.com
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In response to Re: Why clearing the VM doesn't require registering vm buffer in wal record  (Andres Freund <andres@anarazel.de>)
Responses Re: Why clearing the VM doesn't require registering vm buffer in wal record
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On Thu, Mar 5, 2026 at 3:38 PM Andres Freund <andres@anarazel.de> wrote:
> If checksums are enabled, we are already emitting FPIs for the VM when
> *setting* bits in the VM (c.f. log_heap_visible()). I don't see why the story
> for clearing it should be different.  And because there are so few VM pages
> compared to heap pages, I wouldn't expect there to be a meaningful amount of
> VM FPIs outside of very contrived workloads.

Yeah, that's how it seems to me, too, at least as of this moment.

Is there any indication in the code or comments that this was an
intentional omission because somebody thought we could get away
without doing it? Or is just a straight-up goof?

--
Robert Haas
EDB: http://www.enterprisedb.com

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