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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Mark Kirkwood <mark.kirkwood@gmail.com>
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Subject: Re: Unexpected planner choice in simple JOIN
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Comments: In-reply-to Mark Kirkwood <mark.kirkwood@gmail.com>
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Mark Kirkwood <mark.kirkwood@gmail.com> writes:
> Good suggestion. The results are...interesting:

It's clear that the planner is underestimating the costs of using a
parallel worker in your setup.  Try increasing parallel_setup_cost
and/or parallel_tuple_cost to bring things more in line with reality.

			regards, tom lane