On Sat, Jul 18, 2020 at 3:04 PM Jeff Davis <pg...@j-davis.com> wrote: > > I think the entire discussion > > is way out ahead of any field evidence that we need such a knob. > > In the absence of evidence, our default position ought to be to > > keep it simple, not to accumulate backwards-compatibility kluges. > > Fair enough. I think that was where Stephen and Amit were coming from, > as well.
> That would lessen the number of changed plans, but we could easily > remove the pessimization without controversy later if it turned out to > be unnecessary, or if we further optimize HashAgg IO. Does this mean that we've reached a final conclusion on hashagg_avoid_disk_plan for Postgres 13, which is that it should be removed? If so, I'd appreciate it if you took care of it. I don't think that we need to delay its removal until the details of the HashAgg cost pessimization are finalized. (I expect that that will be totally uncontroversial.) Thanks -- Peter Geoghegan
