Re: eliminate xl_heap_visible to reduce WAL (and eventually set VM on-access)

> On 12 Jul 2025, at 03:19, Melanie Plageman <melanieplageman@gmail.com> wrote:
>
> remove the xl_heap_visible struct

Same goes for VISIBILITYMAP_XLOG_CATALOG_REL and XLOG_HEAP2_VISIBLE. But please do not rush to remove it, perhaps I
willhave a more exhaustive list later. Currently the patch set is expected to be unpolished. 
I just need to absorb all effects to have a high-level evaluation of the patch set effect.

I'm still trying to grasp connection of first patch with Assert(prstate->cutoffs) to other patches;

Also, I'd prefer "page is not marked all-visible but visibility map bit is set in relation" to emit XX001 for
monitoringreasons, but again, this is small note, while I need a broader picture. 

So far I do not see any general problems in delegating redo work from xl_heap_visible to other record. FWIW I observed
severalcases of VM corruptions that might be connected to the fact that we log VM changes independently of data changes
thatcaused VM to change. But I have no real evidence or understanding what happened. 


Best regards, Andrey Borodin.