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Re: why do optimizer parameters have to be set manually?

From: William Yu <wyu(at)talisys(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: why do optimizer parameters have to be set manually?
Date: 2003-12-19 17:44:17
Message-ID: brvddd$1u7p$1@news.hub.org (view raw or flat)
Thread:
Lists: pgsql-performance
Tom Lane wrote:
> easy or cheap to get a measurement that isn't skewed by kernel caching
> behavior.  (You need a test file significantly larger than RAM, and
> even then you'd better repeat the measurement quite a few times to see
> how much noise there is in it.)

I found a really fast way in Linux to flush the kernel cache and that is 
to unmount the drive and then remount. Beats having to read though a 
file > RAM everytime.


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