On Tue, 20 Sept 2022 at 13:23, Tom Lane <t...@sss.pgh.pa.us> wrote: > > David Rowley <dgrowle...@gmail.com> writes: > > Aside from that, I don't have any ideas on how to get rid of the > > possible additional datumCopy() from non-Var arguments to these window > > functions. Should we just suffer it? It's quite likely that most > > arguments to these functions are plain Vars anyway. > > No, we shouldn't. I'm pretty sure that we have various window > functions that are deliberately designed to take advantage of the > no-copy behavior, and that they have taken a significant speed > hit from your having disabled that optimization. I don't say > that this is enough to justify reverting the chunk header changes > altogether ... but I'm completely not satisfied with the current > situation in HEAD.
Maybe you've forgotten that MemoryContextContains() is broken in the back branches or just don't think it is broken? David
