From: Tom Lane <tgl@sss.pgh.pa.us>
To: Maxim Boguk <maxim.boguk@gmail.com>
cc: David Rowley <dgrowleyml@gmail.com>, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18588: Cannot force/let database use parallel execution in
 simple case.
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Comments: In-reply-to Maxim Boguk <maxim.boguk@gmail.com>
	message dated "Thu, 22 Aug 2024 23:27:24 +0300"
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Date: Thu, 22 Aug 2024 16:52:43 -0400
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Maxim Boguk <maxim.boguk@gmail.com> writes:
> With sufficiently large table - I didn't manage find a combinations of
> settings to force parallel execution (im my real case - the database huge
> and mostly cold on ssd raid - so parallel execution provides almost linear
> speedup with amount of parallel workers even on 1000 rows... not talking
> about 10k-10m rows, but I cannot convince the PostgreSQL use parallel index
> scan for 2m returned rows case).

Well, there may be something going on in your real case that isn't
apparent from this toy example.  Perhaps look for a better example?

			regards, tom lane