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Date: Thu, 19 Jul 2007 02:48:37 +0200
From: Rene Herman <rene.herman@gmail.com>
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To: Matt Mackall <mpm@selenic.com>
CC: Andrea Arcangeli <andrea@suse.de>, Ray Lee <ray-lk@madrabbit.org>,
       Bodo Eggert <7eggert@gmx.de>, 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 07/19/2007 02:41 AM, Matt Mackall wrote:

> On Thu, Jul 19, 2007 at 02:15:39AM +0200, Andrea Arcangeli wrote:

>> Using kmalloc(8k) instead of alloc_page() doesn't sound a too big deal
>> and that will solve the problem.
> 
> How do you figure?
> 
> If you're saying that soft pages helps our 8k stack allocations, it
> doesn't. The memory overhead of soft pages will be higher (5-15%,
> mostly due to file tails in pagecache) than the level at which 8k
> stacks currently run into trouble (1-2% free?).
> 
> Not helpful.

With tail-packing it is.

Rene.