On Thu, Dec 5, 2019 at 1:12 PM Bruce Momjian <bruce@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.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company