On Mon, Apr 20, 2026 at 6:38 PM JoongHyuk Shin <sjh910805(at)gmail(dot)com> wrote:
> Since MultiXact member lists are immutable once created, cached entries
> stay valid regardless of transaction boundaries.
MultiXactIds are assigned again after wraparound, so a backend that
stays connected across a wraparound can still hold a cache entry for an
old MultiXactId. If that backend then looks up a new MultiXact that
received the same MultiXactId, it may get the old member list back.
I think the patch needs additional design work to handle this case, and
after fixing that it would also need measurements showing a real
performance gain. So for now I have marked the CF entry as Withdrawn.
--
JoongHyuk Shin
>