Re: Removing more vacuumlazy.c special cases, relfrozenxid optimizations

On Sat, Feb 19, 2022 at 7:01 PM Andres Freund <andres@anarazel.de> wrote:
> It's kind of surprising that this needs this
> 0001-Add-adversarial-ConditionalLockBuff to break. I suspect it's a question
> of hint bits changing due to lazy_scan_noprune(), which then makes
> HeapTupleHeaderIsHotUpdated() have a different return value, preventing the
> "If the tuple is DEAD and doesn't chain to anything else"
> path from being taken.

That makes sense as an explanation. Goes to show just how fragile the
"DEAD and doesn't chain to anything else" logic at the top of
heap_prune_chain really is.

-- 
Peter Geoghegan