From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Thomas Munro <thomas.munro@gmail.com>,
        Etsuro Fujita <etsuro.fujita@gmail.com>,
        Alexander Lakhin <exclusion@gmail.com>,
        pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #17828: postgres_fdw leaks file descriptors on error and
 aborts aborted transaction in lack of fds
In-reply-to: <20240209000734.st2xwkfsrz7izbnx@awork3.anarazel.de>
References: <17828-122da8cba23236be@postgresql.org>
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 <974582.1707411864@sss.pgh.pa.us>
 <20240208215920.myib264liwbkdndp@awork3.anarazel.de>
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 <20240209000734.st2xwkfsrz7izbnx@awork3.anarazel.de>
Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Thu, 08 Feb 2024 16:07:34 -0800"
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Date: Thu, 08 Feb 2024 19:20:35 -0500
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Andres Freund <andres@anarazel.de> writes:
> I might be missing something here, but leaving the concrete crash aside,=
 why
> is it ok for pgfdw_get_cleanup_result() etc to block during abort proces=
sing?

It's not pretty, for sure.  I thought briefly about postponing the
cleanup until we next try to use the connection, but I fear the
semantic side-effects of that would be catastrophic.  We can't leave
the remote's query sitting open long after the local transaction has
been canceled --- that risks undetected deadlocks, at the least.
I think all we can do is try to reduce the risk of failure during
transaction cleanup.

			regards, tom lane