On Wed, Jul 14, 2021 at 9:22 PM David Rowley <dgrowle...@gmail.com> wrote: > > On Thu, 15 Jul 2021 at 12:30, Ranier Vilela <ranier...@gmail.com> wrote: > > > > Em qua., 14 de jul. de 2021 às 21:21, David Rowley <dgrowle...@gmail.com> > > escreveu: > >> But, in v8 there is no additional branch, so no branch to mispredict. > >> I don't really see how your explanation fits. > > > > In v8 the branch occurs at : > > + if (ExecGetResultType(outerPlanState(sortstate))->natts == 1) > > You do know that branch is in a function that's only executed once > during executor initialization, right?
This is why I have a hard time believing there's a "real" change here and not the result of either noise or something not really controllable like executable layout changing. James
