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From: James A Sutherland <jas88@cam.ac.uk>
To: war <war@starband.net>, linux-kernel@vger.kernel.org
Subject: Re: Swap vs No Swap.
Date: Thu, 22 Nov 2001 18:08:43 +0000
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On Thursday 22 November 2001 5:56 pm, war wrote:
> This is incorrect.
> SWAP is used on a [1GB ram/2GB swap system].

As it should be. Page out unused data to make room for more cache. This 
*should* improve performance overall. (Yes, latency suffers to boost 
throughput. A fairly common tradeoff; you'll be glad of it under heavier 
load...)

You have "enough" RAM in that the machine doesn't crash under load, but NOT 
enough that swap would go unused.

> I talked to Rik about this.
> He said generally SWAP is a good thing and increases performance.
>
> However, in my case it does not.

As I've said, the VM doesn't always make the right choice :)


James.
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