Message-ID: <494174C4.9040203@agliodbs.com>
Date: Thu, 11 Dec 2008 12:15:00 -0800
From: Josh Berkus <josh@agliodbs.com>
Organization: Aglio Database Solutions
User-Agent: Thunderbird 2.0.0.18 (Macintosh/20081105)
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To: Tom Lane <tgl@sss.pgh.pa.us>
CC: Scott Carey <scott@richrelevance.com>, jd@commandprompt.com,
	Merlin Moncure <mmoncure@gmail.com>,
	Scott Marlowe <scott.marlowe@gmail.com>,
	Jean-David Beyer <jeandavid8@verizon.net>, pgsql-performance@postgresql.org
Subject: Re: Need help with 8.4 Performance Testing
References: <C5642B9E.F8A%scott@richrelevance.com>
	<22285.1228862315@sss.pgh.pa.us>
In-Reply-To: <22285.1228862315@sss.pgh.pa.us>
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Tom,

> Hmm ... I wonder whether this means that the current work on
> parallelizing I/O (the posix_fadvise patch in particular) is a dead
> end.  Because what that is basically going to do is expend more CPU
> to improve I/O efficiency.  If you believe this thesis then that's
> not the road we want to go down.

Nope.  People who adminster small databases keep forgetting that there 
is another class of users with multiple terabytes of data.  Those users 
aren't getting away from spinning disk anytime in the next 5 years.

Additionally, but making PostgreSQL work better with OS-based FS 
optimization, we are well positioned to take advantage of any special 
features which Linux, Solaris, BSD etc. add to utilize new hardware like 
SSDs.  posix_fadvise is a great example of this.

--Josh