From: Mark Felder <feld@feld.me>
To: pgsql-admin@postgresql.org
Subject: Re: Postgresql 9.0.2 explain analyze very slow (10x), compared to actual query time
Date: Wed, 12 Jan 2011 11:17:28 -0600
Message-ID: <op.vo7gzdoo34t2sn@tech304> (raw)
In-Reply-To: <27365.1294850720@sss.pgh.pa.us>
References: <201101111753.22602.achill@matrix.gatewaynet.com>
<201101121318.44007.achill@matrix.gatewaynet.com>
<25677.1294844873@sss.pgh.pa.us>
<201101121817.11143.achill@matrix.gatewaynet.com>
<27365.1294850720@sss.pgh.pa.us>
On Wed, 12 Jan 2011 10:45:20 -0600, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> The short of it is that cheap motherboards tend to provide cheap clock
> hardware that takes about a microsecond to read.
I'm not sure how gettimeofday() works, but is there a slight chance this
could be alleviated by choosing a different kern.timecounter.hardware
option?
kern.timecounter.choice: TSC(800) HPET(900) ACPI-fast(1000) i8254(0)
dummy(-1000000)
kern.timecounter.hardware: ACPI-fast
Or does the kernel timer stuff have nothing to do with gettimeofday()?
Regards,
Mark
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To: pgsql-admin@postgresql.org
Cc: feld@feld.me
Subject: Re: Postgresql 9.0.2 explain analyze very slow (10x), compared to actual query time
In-Reply-To: <op.vo7gzdoo34t2sn@tech304>
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