Date: Fri, 2 Apr 2021 11:34:36 -0400
From: Bruce Momjian <bruce@momjian.us>
To: "Campbell, Lance" <lance@illinois.edu>
Cc: Laurenz Albe <laurenz.albe@cybertec.at>,
	MichaelDBA <MichaelDBA@sqlexec.com>,
	SASIKUMAR Devaraj <sashikumard@yahoo.com>,
	"holger@jakobs.com" <holger@jakobs.com>,
	"pgsql-admin@lists.postgresql.org" <pgsql-admin@lists.postgresql.org>
Subject: Re: work_mem
Message-ID: <20210402153436.GE9270@momjian.us>
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On Fri, Apr  2, 2021 at 03:25:04PM +0000, Campbell, Lance wrote:
> Thanks for sharing this thread.  My suggestion of having a work_mem_stack_size
> is the same concept mentioned in this thread regarding having a work_mem_pool. 
> I prefer this later term rather than the one I was using.  When the work mem
> pool is exhausted PostgreSQL just uses temp files for work_mem.  With current
> statics for temp files and with a new stats on a work mem pool usage a user
> could fine tune memory much more precisely.  It would leave the “art of memory
> tuning” behind.  The other added benefit is that people would have a better
> understanding of how work_mem is used by naturally having to explain what a
> work_mem_pool is and when it is drawn on.  There are probably a lot of
> PostgreSQL instance that would run faster just by having the confidence to
> increase the size of work_mem.  I am sure many instances have this value set to
> low.

Uh, did you read the blog before it, referenced in that blog entry:

	https://momjian.us/main/blogs/pgblog/2018.html#December_7_2018

Even if we have a pool, it is still complex to configure memory, but it
might help.

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

  If only the physical world exists, free will is an illusion.