On Fri, Dec 6, 2019 at 9:20 AM Robert Haas <robertmh...@gmail.com> wrote: > > On Thu, Dec 5, 2019 at 1:12 PM Bruce Momjian <br...@momjian.us> wrote: > > I agree with Stephen's request. We have been waiting for the executor > > rewrite for a while, so let's just do something simple and see how it > > performs. > > I'm sympathetic to the frustration here, and I think it would be great > if we could find a way forward that doesn't involve waiting for a full > rewrite of the executor. However, I seem to remember that when we > tested the various patches that various people had written for this > feature (I wrote one, too) they all had a noticeable performance > penalty in the case of a plain old Append that involved no FDWs and > nothing asynchronous. I don't think it's OK to have, say, a 2% > regression on every query that involves an Append, because especially > now that we have partitioning, that's a lot of queries. > > I don't know whether this patch has that kind of problem. If it > doesn't, I would consider that a promising sign.
I'll look into that. If there is a measurable impact, I suspect it can be avoided by, for example, installing a different ExecProcNode function.
