From: Tom Lane <tgl@sss.pgh.pa.us>
To: depesz@depesz.com
cc: PostgreSQL General <pgsql-general@lists.postgresql.org>,
        Andres Freund <andres@anarazel.de>
Subject: Re: Interesting fail when migrating Pg from Ubuntu Bionic to Focal
In-reply-to: <20220304204510.GA21340@depesz.com>
References: <20220303150428.GA26036@depesz.com>
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 <20220304204510.GA21340@depesz.com>
Comments: In-reply-to hubert depesz lubaczewski <depesz@depesz.com>
	message dated "Fri, 04 Mar 2022 21:45:10 +0100"
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Date: Fri, 04 Mar 2022 17:03:14 -0500
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hubert depesz lubaczewski <depesz@depesz.com> writes:
> On Fri, Mar 04, 2022 at 02:09:52PM -0500, Tom Lane wrote:
>> I tried and failed to reproduce this on Fedora 35 on aarch64,
>> but that has what I think is a newer LLVM version:

> I have suspicion that it also kinda depends on number of rows in there.
> When I deleted some schemas, which included some functions, the problem
> disappeared.
> I wasn't able to pinpoint specific thing, though, and when I called the
> pg_proc + pg_roles query for each separate row - it worked flawlessly.

Mmm ... it might have just been that the planner chose not to use
JIT when it thought there were fewer rows involved.  Did you check
with EXPLAIN that these cut-down cases still used JIT?

			regards, tom lane