čt 11. 12. 2025 v 3:53 odesílatel John Naylor <[email protected]> napsal:
> On Wed, Dec 10, 2025 at 5:20 PM Tomas Vondra <[email protected]> wrote: > > I did however notice an interesting thing - running EXPLAIN on the 99 > > queries (for 3 scales and 0/4 workers, so 6x 99) took this much time: > > > > master: 8s > > master/geqo: 20s > > master/goo: 5s > > > It's nice that "goo" seems to be faster than "geqo" - assuming the plans > > are comparable or better. But it surprised me switching to geqo makes it > > slower than master. That goes against my intuition that geqo is meant to > > be cheaper/faster join order planning. But maybe I'm missing something. > > Yeah, that was surprising. It seems that geqo has a large overhead, so > it takes a larger join problem for the asymptotic behavior to win over > exhaustive search. > If I understand correctly to design - geqo should be slower for any queries with smaller complexity. The question is how many queries in the tested model are really complex. > > -- > John Naylor > Amazon Web Services > > >
