Re: [PATCH] force_parallel_mode and GUC categories

Michael Paquier <michael@paquier.xyz>

From: Michael Paquier <michael@paquier.xyz>
To: Bruce Momjian <bruce@momjian.us>
Cc: Justin Pryzby <pryzby@telsasoft.com>, Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@lists.postgresql.org
Date: 2021-04-12T05:01:17Z
Lists: pgsql-hackers, pgsql-performance
On Fri, Apr 09, 2021 at 07:39:28AM -0400, Bruce Momjian wrote:
> On Thu, Apr  8, 2021 at 10:17:18PM -0500, Justin Pryzby wrote:
>> This is the main motive behind the patch.
>> 
>> Developer options aren't shown in postgresql.conf.sample, which it seems like
>> sometimes people read through quickly, setting a whole bunch of options that
>> sound good, sometimes including this one.  And in the best case they then ask
>> on -performance why their queries are slow and we tell them to turn it back off
>> to fix their issues.  This changes to no longer put it in .sample, and calling
>> it a "dev" option seems to be the classification and mechanism by which to do
>> that.
> 
> +1

Hm.  I can see the point you are making based on the bug report that
has led to this thread:
https://www.postgresql.org/message-id/CAN0SRDFV=Fv0zXHCGbh7gh=MTfw05Xd1x7gjJrZs5qn-TEphOw@mail.gmail.com

However, I'd like to think that we can do better than what's proposed
in the patch.  There are a couple of things to consider here:
- Should the parameter be renamed to reflect that it should only be
used for testing purposes?
- Should we make more general the description of the developer options
in the docs?

I have applied the patch for log_autovacuum_min_duration for now, as
this one is clearly wrong.
--
Michael

Commits

  1. Sync guc.c and postgresql.conf.sample with the SGML docs.

  2. doc: Move force_parallel_mode to section for developer options

  3. Move log_autovacuum_min_duration into its correct sections