Horton

Re: How huge does mvtest_huge need to be?

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Kevin Grittner <kgrittn@gmail.com>
Cc: "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2017-05-03T20:22:31Z
Lists: pgsql-hackers 
Kevin Grittner <kgrittn@gmail.com> writes:
> On Wed, May 3, 2017 at 12:08 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> So ... is there a good reason to be using a large table here, and
>> if so what is it, and how big does the table really need to be
>> to provide useful test coverage?

> Hm.  This seems like a particularly useless size.  It would test a
> possibly useful corner case if it was over 10MB so that it was over
> vacuum's truncation threshold, but that would obviously be even
> slower.  It doesn't seem justified.  How about 500 so it at least
> goes to a second page which is then truncated to 1 page.

Yeah, that aspect occurred to me after a bit too.  I'll make it so.

> The "huge" in the object names then seems odd, of course.

Right ... will pick some other name.

			regards, tom lane

Commits

  1. Remove useless and rather expensive stanza in matview regression test.

  2. Prevent (auto)vacuum from truncating first page of populated matview.