Message-ID: <a949410c-acd6-4a93-b49b-a050dd949671@gmail.com>
Date: Tue, 13 May 2025 06:25:17 +0200
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Subject: Re: inefficient/wrong plan cache mode selection for queries with
 partitioned tables (postgresql 17)
To: Tom Lane <tgl@sss.pgh.pa.us>, Maxim Boguk <maxim.boguk@gmail.com>
Cc: David Rowley <dgrowleyml@gmail.com>,
 Pgsql Performance <pgsql-performance@lists.postgresql.org>
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From: Andrei Lepikhov <lepihov@gmail.com>
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On 5/12/25 20:07, Tom Lane wrote:
> Maxim Boguk <maxim.boguk@gmail.com> writes:
>> Reading the code - probably the lowest hanging fruit is to make
>> 'The current multiplier of 1000 * cpu_operator_cost' configurable in the
>> future versions.
> 
> I'm wondering whether we should try to make the planner not expend
> the effort in the first place, but leave partition pruning to the
> executor, at least in cases where it can determine that that will be
> possible.
Significant planning time is a sorting out lots of scan paths, applying 
partition statistics etc. planner-stage partitioning reduces these 
efforts drastically.

-- 
regards, Andrei Lepikhov