From: Tom Lane <tgl@sss.pgh.pa.us>
To: Bruce Momjian <bruce@momjian.us>
cc: aditya desai <admad123@gmail.com>, Justin Pryzby <pryzby@telsasoft.com>,
        Pgsql Performance <pgsql-performance@lists.postgresql.org>
Subject: Re: SELECT Query taking 200 ms on PostgreSQL compared to 4 ms on
 Oracle after migration.
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Comments: In-reply-to Bruce Momjian <bruce@momjian.us>
	message dated "Sat, 03 Apr 2021 11:12:01 -0400"
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Date: Sat, 03 Apr 2021 11:39:19 -0400
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Bruce Momjian <bruce@momjian.us> writes:
> On Sat, Apr  3, 2021 at 08:38:18PM +0530, aditya desai wrote:
>> Yes, force_parallel_mode is on. Should we set it off?

> Yes.  I bet someone set it without reading our docs:

> 	https://www.postgresql.org/docs/13/runtime-config-query.html#RUNTIME-CO=
NFIG-QUERY-OTHER

> -->	Allows the use of parallel queries for testing purposes even in case=
s
> -->	where no performance benefit is expected.

> We might need to clarify this sentence to be clearer it is _only_ for
> testing.

I wonder why it is listed under planner options at all, and not under
developer options.

			regards, tom lane