Horton
Menu

Re: Change default of jit to off

Jelte Fennema <postgres@jeltef.nl>

View thread
From: "Jelte Fennema-Nio" <postgres@jeltef.nl>
To: "Pierre Ducroquet" <p.psql@pinaraf.info>
Cc: "Tom Lane" <tgl@sss.pgh.pa.us>, "Tomas Vondra" <tomas@vondra.me>, "Andres Freund" <andres@anarazel.de>, "Greg Sabino Mullane" <htamfids@gmail.com>, "Adrien Nayrat" <adrien.nayrat@anayrat.info>, "Christoph Berg" <myon@debian.org>, "Euler Taveira" <euler@eulerto.com>, Álvaro Herrera <alvherre@kurilemu.de>, "PostgreSQL Hackers" <pgsql-hackers@lists.postgresql.org>, "Andreas Karlsson" <andreas@proxel.se>, "Anthonin Bonnefoy" <anthonin.bonnefoy@datadoghq.com>, "pgsql-hackers" <pgsql-hackers@postgresql.org>, "Michael Banck" <mbanck@gmx.net>
Date: 2026-03-24T14:32:36Z
Lists: pgsql-hackers

Attachments

On Mon Mar 23, 2026 at 9:50 AM CET, Jelte Fennema-Nio wrote:
> I think Andres' reply also applied to that suggestion. Partitioning
> really messes up jit for expressions too. I was able to pretty easily
> create some bad cases even with jit_tuple_deforming set to off. A
> query involving many partitions, but with relatively few rows per
> partition, jit became ~54x slower when using -O2 (743ms vs 40318ms).
> And even with -O0, jit is still ~3x slower (221ms vs 711ms). Full
> script and results attached.


Resending the above with a compressed attachment, because it was too
large for the mailing list.

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. jit: Change the default to off.