Re: Old row version in hot chain become visible after a freeze

> > > I also tweaked lazy_record_dead_tuple to fail with ERROR if the tuple
> > > cannot be recorded, as observed by Yi Wen. AFAICS that's not reachable
> > > because of the way the array is allocated, so an elog(ERROR) is
> > > sufficient.
>
> I agree the fail is rare (and probably doesn't happen in real cases, although the comment
> does imply with a sufficiently low working_memory it might?). However, I'd dispute that ERROR
> is sufficient --PANIC is probably appropriate here because FREEZE is not WAL-logged until
> the end of the page; so we'd end up with unfrozen Xids hanging around with an appropriately
> timed crash. I wouldn't worry much about the PANIC tripping because like you said,
> this seems unreachable normally.
>
> The errmsg should come with a errhint saying "Increase maintenance_work_mem".

On closer inspection, I misread the code. The freezes are collected instead of executed, so a ERROR would
suffice. We don't need to change it to PANIC. errhint comment remains.

Yi Wen