> On 29 Jul 2025, at 23:15, Andrey Borodin <x4mmm@yandex-team.ru> wrote:
>
> I do not understand it yet.
OK, I figured it out. SimpleLruDoesPhysicalPageExist() was reading a physical file and could race with real extension
byExtendMultiXactOffset().
So I used ExtendMultiXactOffset(actual + 1). I hope this does not open a loop for wraparound...
Here's an updated two patches, one for Postgres 17 and one for mater(with a test).
Best regards, Andrey Borodin.