Message-ID: <4DDFF1D7.8010606@2ndquadrant.com>
Date: Fri, 27 May 2011 14:47:51 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Merlin Moncure <mmoncure@gmail.com>
CC: postgres performance list <pgsql-performance@postgresql.org>
Subject: Re: The shared buffers challenge
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Merlin Moncure wrote:
> That's just plain unfair: I didn't challenge your suggestion nor give
> you homework.

I was stuck either responding to your challenge, or leaving the 
impression I hadn't done the research to back the suggestions I make if 
I didn't.  That made it a mandatory homework assignment for me, and I 
didn't appreciate that.


> *) the documentation should really explain this better (in particular,
> it should debunk the myth 'more buffers = more caching'

Any attempt to make a serious change to the documentation around 
performance turns into a bikeshedding epic, where the burden of proof to 
make a change is too large to be worth the trouble to me anymore.  I 
first started publishing tuning papers outside of the main docs because 
it was the path of least resistance to actually getting something useful 
in front of people.  After failing to get even basic good 
recommendations for checkpoint_segments into the docs, I completely gave 
up on focusing there as my primary way to spread this sort of information.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us
"PostgreSQL 9.0 High Performance": http://www.2ndQuadrant.com/books