From: Tom Lane <tgl@sss.pgh.pa.us>
To: Sanyo Moura <sanyo.moura@tatic.net>
cc: pgsql-performance@lists.postgresql.org
Subject: Re: Query with high planning time at version 11.1 compared versions
 10.5 and 11.0
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Comments: In-reply-to Sanyo Moura <sanyo.moura@tatic.net>
	message dated "Tue, 27 Nov 2018 12:16:41 -0200"
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Date: Tue, 27 Nov 2018 10:00:08 -0500
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Sanyo Moura <sanyo.moura@tatic.net> writes:
> And below are the times generated by EXPLAIN ANALYZE:

> 10.5
> Planning time: 126.080 ms
> Execution time: 2.306 ms

> 11.0
> Planning Time: 7.238 ms
> Planning Time: 2.638 ms

> 11.5        (I assume you mean 11.1 here)
> Planning Time: 15138.533 ms
> Execution Time: 2.310 ms

There were no changes between 11.0 and 11.1 that look like they'd affect
planning time.  Nor does it seem particularly credible that planning time
would have dropped by a factor of 15 between 10.x and 11.x, especially
not given that the resulting plan didn't change.  I think you've got some
external factor causing long planning times --- maybe something taking an
exclusive lock on one of the tables, or on pg_statistic?

			regards, tom lane