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Date: Thu, 20 Apr 2006 17:20:58 -0700 (PDT)
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To: piet@bluelane.com
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Subject: Re: Linux 2.6.17-rc2
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From: Piet Delaney <piet@bluelane.com>
Date: Thu, 20 Apr 2006 14:37:11 -0700

> What about marking the pages Read-Only while it's being used by the
> kernel and if the user tries to write into them letting the VM dup 
> the page with the COW code?

That's historically how you kill performance.