Message-ID: <4F47A48C.6000302@lerner.co.il>
Date: Fri, 24 Feb 2012 16:54:04 +0200
From: "Reuven M. Lerner" <reuven@lerner.co.il>
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To: sthomas@peak6.com
CC: Glyn Astill <glynastill@yahoo.co.uk>,
	"pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
Subject: Re: Very long deletion time on a 200 GB database
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	<1329990620.15378.YahooMailNeo@web171403.mail.ir2.yahoo.com>
	<4F4730B4.2050602@lerner.co.il> <4F479FDE.1070509@peak6.com>
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Hi, everyone.  Shaun said:
> On 02/24/2012 12:39 AM, Reuven M. Lerner wrote:
>
>> - CPU is virtually idle when running the deletes, using about 1% of
>> CPU
>
> I think you found your problem.
>
> See if you can get the Windows admins to give you some info on how busy
> the disks are (percent utilization, IOPS, something) the next time you
> try this. Increasing your memory settings may help, but a 1% CPU usage
> usually suggests it's waiting for disk blocks to be read before it can
> actually do something.

I asked them for disk readings, but I'm not sure how to contextualize 
the numbers I got:

I/O writes: process1: 820,000, process2: 1Milion Process3: 33,000

Any suggestions for what I can do to improve performance with such a 
slow disk, and a lack of additional RAM?

Reuven

-- 
Reuven M. Lerner -- Web development, consulting, and training
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