From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        Michael Paquier <michael@paquier.xyz>,
        Andres Freund <andres@anarazel.de>,
        Thomas Munro <thomas.munro@enterprisedb.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: subscriptionCheck failures on nightjar
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Tue, 17 Sep 2019 11:54:45 -0400"
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Date: Tue, 17 Sep 2019 12:39:33 -0400
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Robert Haas <robertmhaas@gmail.com> writes:
> On Mon, Aug 26, 2019 at 9:29 AM Tomas Vondra
> <tomas.vondra@2ndquadrant.com> wrote:
>> This is one of the remaining open items, and we don't seem to be moving
>> forward with it :-(

> Why exactly is this an open item, anyway?

The reason it's still here is that Andres expressed a concern that
there might be more than meets the eye in this.  What meets the eye
is that PANICing on file-not-found is not appropriate here, but Andres
seemed to think that the file not being present might reflect an
actual bug not just an expectable race condition [1].

Personally I'd be happy just to treat it as an expectable case and
fix the code to not PANIC on file-not-found.

In either case, it probably belongs in the "older bugs" section;
nightjar is showing the same failure on v11 from time to time.

			regards, tom lane

[1] https://www.postgresql.org/message-id/20190213215147.cjbymfojf6xndr4t%=
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