pg.ddx.io  pgsql-bugs@postgresql.org mailing list archive  

help / color / mirror / Atom feed
From: Noah Misch <noah@leadboat.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Francesco Degrassi <francesco.degrassi@optionfactory.net>
Cc: pgsql-bugs@lists.postgresql.org
Subject: Re: Leader backend hang on IPC/ParallelFinish when LWLock held at parallel query start
Date: Fri, 8 Nov 2024 09:31:12 -0800
Message-ID: <20241108173112.c7.nmisch@google.com> (raw)
In-Reply-To: <3694355.1731084396@sss.pgh.pa.us>
References: <CAC-SaSzHUKT=vZJ8MPxYdC_URPfax+yoA1hKTcF4ROz_Q6z0_Q@mail.gmail.com>
	<20240918030159.2a.nmisch@google.com>
	<1737570.1726633422@sss.pgh.pa.us>
	<20240918050434.13.nmisch@google.com>
	<3441950.1730999841@sss.pgh.pa.us>
	<20241107192233.94.nmisch@google.com>
	<3459938.1731007759@sss.pgh.pa.us>
	<20241107193823.dc.nmisch@google.com>
	<3694355.1731084396@sss.pgh.pa.us>

On Fri, Nov 08, 2024 at 11:46:36AM -0500, Tom Lane wrote:
> Noah Misch <noah@leadboat.com> writes:
> > On Thu, Nov 07, 2024 at 02:29:19PM -0500, Tom Lane wrote:
> >> Ah, that could be a way out.  Stick an INTERRUPTS_CAN_BE_PROCESSED()
> >> call somewhere in there?
> 
> > Exactly.  If !INTERRUPTS_CAN_BE_PROCESSED(), proceed as though no workers can
> > be launched.
> 
> >> That could even allow us to revert the
> >> planner change, which would simplify testing of the executor change.
> 
> > True.
> 
> Here's a proposed patch along that line.  I left the test case from
> ac04aa84a alone, since it works perfectly well to test this way too.
> 
> We could argue about whether or not to revert the planner change.
> But I'd prefer to do so, because as things stand it creates a
> hard-to-reason-about source of plan instability.

Looks perfect.  Thank you.





view thread (18+ messages)  latest in thread

Message-ID: <20241108173112.c7.nmisch@google.com>
Permalink:  ../20241108173112.c7.nmisch@google.com/
Also on:    postgresql.org/message-id/20241108173112.c7.nmisch@google.com

 · 

reply
Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-bugs@postgresql.org
  Cc: noah@leadboat.com, tgl@sss.pgh.pa.us, francesco.degrassi@optionfactory.net, pgsql-bugs@lists.postgresql.org
  Subject: Re: Leader backend hang on IPC/ParallelFinish when LWLock held at parallel query start
  In-Reply-To: <20241108173112.c7.nmisch@google.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox