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Date: Tue, 17 Jul 2007 00:55:36 +0200
From: Rene Herman <rene.herman@gmail.com>
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To: Ray Lee <ray-lk@madrabbit.org>
CC: Bodo Eggert <7eggert@gmx.de>, Matt Mackall <mpm@selenic.com>,
       Jeremy Fitzhardinge <jeremy@goop.org>,
       Jesper Juhl <jesper.juhl@gmail.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       William Lee Irwin III <wli@holomorphy.com>, David Chinner <dgc@sgi.com>,
       Arjan van de Ven <arjan@infradead.org>
Subject: Re: [PATCH][RFC] 4K stacks default, not a debug thing any more...?
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On 07/17/2007 12:37 AM, Ray Lee wrote:

> On 7/16/07, Rene Herman <rene.herman@gmail.com> wrote:

>> Seeing as how single-page stacks are much easier on the VM so that 
>> creating those zillion threads should also be faster, at _some_
>> percentage we get to say "and now to hell with the rest".
> 
> This is the core dispute here. Stated differently, I hope you never
> design a bridge that I have to drive over.
> 
> Correctness first, optimization second. Introducing random and
> difficult to trace crashes upon an unsuspecting audience of sysadmins
> and users is not a viable option.

Quite. But unfortunately you didn't actually go into the bit on how given 
seperate interrupt stacks, available stackspace might not actually _be_ less 
after selecting CONFIG_4KSTCKS nor into Fedora and RHEL shipping it already.

> If at some point one of the pro-4k stacks crowd can prove that all
> code paths are safe

I'll do that the minute you prove the current shared 8K stacks are safe. Do 
we have a deal?

> or introduce another viable alternative (such as Matt's idea for
> extending the stack dynamically), then removing the 8k stacks option
> makes sense.

I'm still waiting for larger soft-pages... does anyone in this thread have a 
clue on their status?

Rene.