On Mon, Jul 20, 2020 at 09:17:21AM -0400, Tom Lane wrote:
Tomas Vondra <tomas.von...@2ndquadrant.com> writes:
There's a minor problem here, though - these stats were collected before
we fixed the tlist issue, so hashagg was spilling about 10x the amount
of data compared to sort+groupagg. So maybe that's the first thing we
should do, before contemplating changes to the costing - collecting
fresh data. I can do that, if needed.
+1. I'm not sure if we still need to do anything, but we definitely
can't tell on the basis of data that doesn't reliably reflect what
the code does now.
OK, will do. The hardware is busy doing something else at the moment,
but I'll do the tests and report results in a couple days.
regards
--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
