From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Thomas Munro <thomas.munro@enterprisedb.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: subscriptionCheck failures on nightjar
In-reply-to: <20190213183303.ns54frt7cmvo6pgg@alap3.anarazel.de>
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Wed, 13 Feb 2019 10:33:03 -0800"
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Date: Wed, 13 Feb 2019 14:11:26 -0500
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Andres Freund <andres@anarazel.de> writes:
> I was kinda pondering just open coding it.  I am not yet convinced that
> my idea of just using an open FD isn't the least bad approach for the
> issue at hand.  What precisely is the NFS issue you're concerned about?

I'm not sure that fsync-on-FD after the rename will work, considering that
the issue here is that somebody might've unlinked the file altogether
before we get to doing the fsync.  I don't have a hard time believing that
that might result in a failure report on NFS or similar.  Yeah, it's
hypothetical, but the argument that we need a repeat fsync at all seems
equally hypothetical.

> Right now fsync_fname_ext isn't exposed outside fd.c...

Mmm.  That makes it easier to consider changing its API.

			regards, tom lane