Re: Auto-tuning work_mem and maintenance_work_mem - Mailing list pgsql-hackers

From Andres Freund
Subject Re: Auto-tuning work_mem and maintenance_work_mem
Date
Msg-id 20140217183947.GD7161@awork2.anarazel.de
Whole thread Raw
In response to Re: Auto-tuning work_mem and maintenance_work_mem  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: Auto-tuning work_mem and maintenance_work_mem  (Bruce Momjian <bruce@momjian.us>)
List pgsql-hackers
On 2014-02-17 13:33:17 -0500, Robert Haas wrote:
> On Mon, Feb 17, 2014 at 11:33 AM, Andres Freund <andres@2ndquadrant.com> wrote:
> >> And I still disagree with this- even in those cases.  Those same untuned
> >> servers are running dirt-simple queries 90% of the time and they won't
> >> use any more memory from this, while the 10% of the queries which are
> >> more complicated will greatly improve.
> >
> > Uh. Paging.
> 
> What about it?

It's often the source of a good portion of the queries and load in web
applications. Multiple joins and more than one row... I have several
time seen stats changes or bad to-be-sorted columns cause large amounts
of memory to be used.

Anyway, I've stated my opinion that I do not think it's a good idea to
raise that particular default (while agreeing with all the others) and I
know I am in the minority, so I don't think we need to argue this out...

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
Services



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