On Tue, 11 Feb 2025 at 00:20, Nathan Bossart <nathandboss...@gmail.com> wrote: > > On Mon, Feb 10, 2025 at 06:17:42PM +0100, Matthias van de Meent wrote: > > I have serious doubts about the viability of any proposal working to > > implement PHOT/WARM in PostgreSQL, as they seem to have an inherent > > nature of fundamentally breaking the TID lifecycle: > > [... concerns] > > I share your concerns, but I don't think things are as dire as you suggest. > For example, perhaps we put a limit on how long a PHOT chain can be, or > maybe we try to detect update patterns that don't work well with PHOT. > Another option could be to limit PHOT updates to only when the same set of > indexed columns are updated or when <50% of the indexed columns are > updated. These aren't fully fleshed-out ideas, of course, but I am at > least somewhat optimistic we could find appropriate trade-offs.
Yes, there are methods which could limit the overhead. But I'm not sure there are cheap-enough designs which would make PHOT a universally good choice (i.e. not tunable with guc/table option), considering its significantly larger un-reclaimable storage overhead vs HOT. Kind regards, Matthias van de Meent.
