Message-ID: <4CC34D8A.4050606@agliodbs.com>
Date: Sat, 23 Oct 2010 14:03:06 -0700
From: Josh Berkus <josh@agliodbs.com>
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To: pgsql-performance@postgresql.org
Subject: Re: BBU Cache vs. spindles
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> Even if it's possible, it's far from clear to me that it would be an
> improvement.  The author estimates (apparently somewhat loosely)
> that it's a 5% to 10% performance hit in InnoDB; I'm far from
> certain that full_page_writes cost us that much.  Does anyone have
> benchmark numbers handy?

It most certainly can, depending on your CPU saturation and I/O support. 
   I've seen a 10% improvement in througput time from turning off 
full_page_writes on some machines, such as when we were doing the 
SpecJAppserver benchmarks on Solaris.

-- 
                                   -- Josh Berkus
                                      PostgreSQL Experts Inc.
                                      http://www.pgexperts.com