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Date: Sun, 18 Nov 2001 16:28:01 -0500
From: war <war@starband.net>
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To: James A Sutherland <jas88@cam.ac.uk>
CC: linux-kernel@vger.kernel.org
Subject: Re: Swap
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Well, without the swap, everything seems to be about 100% more responsive when
I execute any task.
I see how it works now.

James A Sutherland wrote:

> On Sunday 18 November 2001 9:12 pm, war wrote:
> > It is amazing that I could run all of that stuff, because:
> >
> > When I have swap on, and if I run all of those programs, 200-400MB of
> > swap is used.
>
> Yep. There's a reason for that: the kernel is *ALWAYS* able to swap pages out
> to disk - even without "swap space". Disabling swapspace simply forces the
> kernel to swap out more code, since it cannot swap out any data.
>
> (This is why you can still get "disk thrashing" without any swap - in fact,
> it's more likely in this case than it is with some swap added - you are just
> forcing your binaries to take more of the swapping load instead.)
>
> So: with swapspace, the kernel swaps out a few hundred Mb of unused data, to
> make room for more code. Without it, the kernel is forced to swap out code
> pages instead. The big news here is...?
>
> James.

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