From: Tom Lane <tgl@sss.pgh.pa.us>
To: ilmari@ilmari.org (Dagfinn Ilmari =?utf-8?Q?Manns=C3=A5ker?=)
cc: "Daniel Verite" <daniel@manitou-mail.org>,
        "movead.li\@highgo.ca" <movead.li@highgo.ca>,
        "ashutosh.bapat" <ashutosh.bapat@2ndquadrant.com>,
        "pgsql-hackers" <pgsql-hackers@lists.postgresql.org>
Subject: Re: A bug when use get_bit() function for a long bytea string
In-reply-to: <87y2rdtuug.fsf@wibble.ilmari.org>
References: <84525289-3891-4368-9157-5452f53a6908@manitou-mail.org>
 <563.1585857846@sss.pgh.pa.us> <87y2rdtuug.fsf@wibble.ilmari.org>
Comments: In-reply-to ilmari@ilmari.org (Dagfinn Ilmari
 =?utf-8?Q?Manns=C3=A5ker?=)
	message dated "Thu, 02 Apr 2020 22:56:39 +0100"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <22817.1585866068.1@sss.pgh.pa.us>
Date: Thu, 02 Apr 2020 18:21:08 -0400
Message-ID: <22818.1585866068@sss.pgh.pa.us>
Precedence: bulk

ilmari@ilmari.org (Dagfinn Ilmari =?utf-8?Q?Manns=C3=A5ker?=) writes:
> Tom Lane <tgl@sss.pgh.pa.us> writes:
>> Yeah, I'd noticed those on previous readings of the patch.  They'd almost
>> certainly fail on some of our older/smaller buildfarm members, so they're
>> not getting committed, even if they didn't require multiple seconds apiece
>> to run (even on a machine with plenty of memory).  It's useful to have
>> them for initial testing though.

> Perl's test suite has a similar issue with tests for handling of huge
> strings, hashes, arrays, regexes etc.  We've taken the approach of
> checking the environment variable PERL_TEST_MEMORY and skipping tests
> that need more than that many gigabytes.  We currently have tests that
> check for values from 1 all the way up to 96 GiB.
> This would be trivial to do in the Postgres TAP tests, but something
> similar might feasible in the pg_regress too?

Meh.  The memory is only part of it; the other problem is that multiple
seconds expended in every future run of the regression tests is a price
that's many orders of magnitude higher than the potential value of this
test case.

			regards, tom lane