From: Alan Hodgson <ahodgson@simkin.ca>
To: pgsql-performance@postgresql.org
Subject: Re: CPU utilization vs. IO wait, shared buffers?
Date: Thu, 30 Oct 2008 14:48:58 -0700
Message-ID: <200810301448.58941@hal.medialogik.com> (raw)
In-Reply-To: <db7814e50810301441h458aaf60k515548973a5a5297@mail.gmail.com>
References: <db7814e50810301441h458aaf60k515548973a5a5297@mail.gmail.com>
On Thursday 30 October 2008, "Oliver Johnson" <oliverjjohnson@gmail.com>
wrote:
> Another thing to note, we have VACUUM ANALYZE running on an hourly
> interval and the switch from CPU to IO wait appears to always coincide
> with a vacuum.
>
> What might cause this shift?
The extra disk access caused by vacuum? That seems pretty obvious.
Use auto-vacuum. There's no reason to vacuum your entire database every hour
(doing so reads from disk the entirety of every table and index, and
generates some write activity).
--
Alan
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To: pgsql-performance@postgresql.org
Cc: ahodgson@simkin.ca
Subject: Re: CPU utilization vs. IO wait, shared buffers?
In-Reply-To: <200810301448.58941@hal.medialogik.com>
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