From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: maxim.boguk@gmail.com, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #17871: JIT during postgresql_fdw remote_estimates EXPLAIN
 have very negatively effect on planning time
In-reply-to: <20230327212830.dpp2u47je5ozf5q7@awork3.anarazel.de>
References: <17871-16521a70c16cb83c@postgresql.org>
 <20230327212830.dpp2u47je5ozf5q7@awork3.anarazel.de>
Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Mon, 27 Mar 2023 14:28:30 -0700"
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Date: Mon, 27 Mar 2023 17:38:19 -0400
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Andres Freund <andres@anarazel.de> writes:
> On 2023-03-27 08:04:59 +0000, PG Bug reporting form wrote:
>> postgresql_fdw remote estimated  explain calls could trigger JIT compil=
ation
>> on the remote side (why explain without analyze trying use JIT at all??=
?),
>> and with partitioned tables it will lead to very slow planning.

> It should not trigger all of JIT, just generating the bitcode, but not
> optimizing / emitting it.

I was wondering if we could skip doing even that much when
EXEC_FLAG_EXPLAIN_ONLY is set.  Without a test case, though,
I'm not very sure where the jitter is getting reached.

			regards, tom lane