From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jeff Davis <jdavis@postgresql.org>
cc: pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Disk-based Hash Aggregation.
In-reply-to: <E1jEhaL-0002Ur-2L@gemulon.postgresql.org>
References: <E1jEhaL-0002Ur-2L@gemulon.postgresql.org>
Comments: In-reply-to Jeff Davis <jdavis@postgresql.org>
	message dated "Wed, 18 Mar 2020 22:54:49 -0000"
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Date: Mon, 23 Mar 2020 02:05:06 -0400
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Jeff Davis <jdavis@postgresql.org> writes:
> Disk-based Hash Aggregation.

I noticed that the regression tests seemed suddenly slower than they
have been.  A bit of poking around reveals that this patch made
groupingsets.sql take approximately 8X longer than it used to,
and more than twice as long as any other core regression test.

This is absolutely, positively, not acceptable for a test that gets
run hundreds of times a day by lots of people and buildfarm animals.

If there's no way to test the feature in some significantly-cheaper way,
perhaps we should move this test out to a separate script that's not run
by default.

			regards, tom lane