Hi, On 2023-03-21 20:20:40 +0100, Matthias van de Meent wrote: > On Tue, 21 Mar 2023 at 19:55, Tom Lane <t...@sss.pgh.pa.us> wrote: > > > > Andres Freund <and...@anarazel.de> writes: > > > FWIW, I think we should consider getting rid of attcacheoff. I doubt it's > > > worth its weight these days, because deforming via slots starts at the > > > beginning anyway. The overhead of maintaining it is not insubstantial, and > > > it's just architecturally ugly to to update tupledescs continually. > > > > I'd be for that if we can convince ourselves there's not a material > > speed penalty. As you say, it's quite ugly. > > Yes, attcacheoff is a tremendous performance boon in many cases.
Which? We don't use fastgetattr() in many places these days. And in some quick measurements it's a wash or small loss when deforming slot tuples, even when the attcacheoff optimization would apply, because the branches for managing it add more overhead than they safe. Greetings, Andres Freund
