Date: Tue, 6 May 2025 16:07:24 -0400
From: Bruce Momjian <bruce@momjian.us>
To: Amit Langote <amitlangote09@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@lists.postgresql.org>,
	David Rowley <dgrowleyml@gmail.com>
Subject: Re: PG 18 release notes draft committed
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On Tue, May  6, 2025 at 03:08:13PM +0900, Amit Langote wrote:
> > I don't think most people would know what EquivalenceMember is, and even
> > if they did, would they be able to connect it to an SQL query?
> 
> Thanks for splitting these (cf847d634). I think the text for the
> locking item should mention “during execution,” as David also
> suggested. Again, I don’t think this change belongs under Optimizer
> since it doesn’t really affect the planner -- it’s mainly an executor
> improvement. Maybe the General Performance section is a better fit.

Yes, good idea, done.

> Also, just to clarify why the individual items are meaningful
> performance improvements:
> 
> * Locking change: Executing cached plans involving hundreds or
> thousands of partitions was bottlenecked by locking; with this change,
> execution is now roughly 20x faster with 1000 partitions.
> 
> * Planning time improvements: Planning certain commonly used queries
> against partitioned tables when they don’t use partition pruning is
> now roughly 20x faster with 1000 partitions.

That's impressive!

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  Do not let urgent matters crowd out time for investment in the future.