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Date: Fri, 27 Jul 2007 08:02:13 -0500
From: Eric Sandeen <sandeen@sandeen.net>
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
CC: Andrea Arcangeli <andrea@suse.de>, Matt Mackall <mpm@selenic.com>,
       Rene Herman <rene.herman@gmail.com>, 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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Alan Cox wrote:
>> I don't think they're necessarily bugs. IMHO the WARN_ON is better off
>> at 7k level like it is today with the current STACK_WARN. 4k for a
>> stack for common code really is small. I doubt you're going to find
> 
> You want the limit settable. On a production system you want to set the
> limit to somewhere appropriate for the stack size used. When debugging
> (eg to remove any last few bogus users of 8K stack space) you want to be
> able to set it to just under 4K

Hm, when cramming cxfs into 4k at sgi, I had a patch that did just that
for debugging (warn about encroaching on 4k without actually tipping
over, with a settable threshold...)

Maybe I should resurrect it & send it out...

(FWIW I think I recall that the warning itself sometimes tipped the
scales enough on 4k stacks to bring the box down)

-eric