From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Kapila <amit.kapila16@gmail.com>
cc: Noah Misch <noah@leadboat.com>, Amit Khandekar <amitdkhan.pg@gmail.com>,
        Alvaro Herrera from 2ndQuadrant <alvherre@alvh.no-ip.org>,
        Andres Freund <andres@anarazel.de>,
        =?UTF-8?Q?Juan_Jos=C3=A9_Santamar=C3=ADa_Flecha?=
 <juanjo.santamaria@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        Robert Haas <robertmhaas@gmail.com>,
        Thomas Munro <thomas.munro@gmail.com>,
        Tomas Vondra <tomas.vondra@2ndquadrant.com>
Subject: Re: logical decoding : exceeded maxAllocatedDescs for .spill files
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Comments: In-reply-to Amit Kapila <amit.kapila16@gmail.com>
	message dated "Sat, 11 Jan 2020 11:06:35 +0530"
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Date: Sat, 11 Jan 2020 00:46:19 -0500
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Amit Kapila <amit.kapila16@gmail.com> writes:
> On Fri, Jan 10, 2020 at 9:31 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
>> ... So, we have the below
>> options:
>> (a) remove this test entirely from all branches and once we found the
>> memory leak problem in back-branches, then consider adding it again
>> without max_files_per_process restriction.
>> (b) keep this test without max_files_per_process restriction till v11
>> and once the memory leak issue in v10 is found, we can back-patch to
>> v10 as well.

> I am planning to go with option (a) and attached are patches to revert
> the entire test on HEAD and back branches.  I am planning to commit
> these by Tuesday unless someone has a better idea.

Makes sense to me.  We've certainly found out something interesting
from this test, but not what it was expecting to find ;-).  I think
that there could be scope for two sorts of successor tests:

* I still like my idea of directly constraining max_safe_fds through
some sort of debug option.  But to my mind, we want to run the entire
regression suite with that restriction, not just one small test.

* The seeming bug in v10 suggests that we aren't testing large enough
logical-decoding cases, or at least aren't noticing leaks in that
area.  I'm not sure what a good design is for testing that.  I'm not
thrilled with just using a larger (and slower) test case, but it's
not clear to me how else to attack it.

			regards, tom lane