Re: [PATCH][RFC] 4K stacks default, not a debug thing any more...?

From: Matt Mackall
Date: Mon Jul 16 2007 - 19:08:28 EST


On Tue, Jul 17, 2007 at 12:55:36AM +0200, Rene Herman wrote:
> On 07/17/2007 12:37 AM, Ray Lee wrote:
>
> >On 7/16/07, Rene Herman <rene.herman@xxxxxxxxx> 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?

Given that most x86 users won't want anything to do with them, it's
not going to help us at all here.

--
Mathematics is the supreme nostalgia of our time.
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