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Date: Thu, 19 Jul 2007 19:20:10 +0200 (CEST)
From: Bodo Eggert <7eggert@gmx.de>
To: Arjan van de Ven <arjan@infradead.org>
cc: Bodo Eggert <7eggert@gmx.de>, Rene Herman <rene.herman@gmail.com>,
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Subject: Re: [PATCH][RFC] 4K stacks default, not a debug thing any more...?
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On Tue, 17 Jul 2007, Arjan van de Ven wrote:

> > 1) It all can be reduced to 4K + 4K by asuming all IRQ happen on one CPU.
> 
> no it's separate stacks for soft and hard irqs, so it's really 4+4+4

Thanks, I missed that information. Unfortunately this change still does 
not help if one of these stacks needs to grow beyond 4K.

> another angle is that while correctness rules, userspace correctness
> rules as well. If you can't fork enough threads for what you need the
> machine for, why have the machine in the first place?

Userspace can't work correctly after the kernel crashed, but it can fail 
gracefully if it can't create enough threads.

I'd really like to be able to select 4K stacks, but as long as that stack
would overflow, I can't, and it can't be default, too.
-- 
Top 100 things you don't want the sysadmin to say:
8. ...and after I patched the microcode...