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Subject: Re: [2.4.17/18pre] VM and swap - it's really unusable
From: Robert Love <rml@tech9.net>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: nigel@nrg.org, Rob Landley <landley@trommello.org>,
        Andrew Morton <akpm@zip.com.au>, linux-kernel@vger.kernel.org
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Date: 11 Jan 2002 15:33:22 -0500
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On Fri, 2002-01-11 at 07:37, Alan Cox wrote:

> Its more than a spinlock cleanup at that point. To do anything useful you have
> to tackle both priority inversion and some kind of at least semi-formal 
> validation of the code itself. At the point it comes down to validating the
> code I'd much rather validate rtlinux than the entire kernel

The preemptible kernel plus the spinlock cleanup could really take us
far.  Having locked at a lot of the long-held locks in the kernel, I am
confident at least reasonable progress could be made.

Beyond that, yah, we need a better locking construct.  Priority
inversion could be solved with a priority-inheriting mutex, which we can
tackle if and when we want to go that route.  Not now.

I want to lay the groundwork for a better kernel.  The preempt-kernel
patch gives real-world improvements, it provides a smoother user desktop
experience -- just look at the positive feedback.  Most importantly,
however, it provides a framework for superior response with our standard
kernel in its standard programming model. 

	Robert Love

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