Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 17 Aug 2001 09:12:16 -0700 (PDT)
From:      Julian Elischer <julian@elischer.org>
To:        "Eugene L. Vorokov" <vel@bugz.infotecs.ru>
Cc:        freebsd-hackers@freebsd.org
Subject:   Re: kernel stack size
Message-ID:  <Pine.BSF.4.21.0108170907430.22899-100000@InterJet.elischer.org>
In-Reply-To: <200108171344.f7HDife37351@bugz.infotecs.ru>

next in thread | previous in thread | raw e-mail | index | archive | help
We may go to 2 pages but really 1 page is enough as long as people 
don't store structures on the stack. It's been kept small to keep the
overhead of processes and threads down. When we get threads (KSE) we may
have theoretically thousands more of these, on potentially smaller boxes..

The main poitn is that it's FIXED and that you can have recursion and
interrupts so kernel programmers should know that a stack is a minimal
resource. To some extent keeping it VERY small helps force this disciplin
on people.

As I said before there is a possibility we may go to 2 pages but 
that's not at all certain.


On Fri, 17 Aug 2001, Eugene L. Vorokov wrote:

> > In 5-0-KSE there is a single page that contains the stack and 
> > the PCB (which is about 660 bytes). We are also looking at adding
> > code to set a hardware watchpoint between the stack and the PCB
> > to catch overruns.
> 
> Maybe I'm just dumb, but I still don't understand, what is the reason of
> keeping kernel stack size so small ? I understand there should be no
> need in huge stack, but why so damn small ? Would someone explain please ?
> 
> Regards,
> Eugene
> 
> 


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.21.0108170907430.22899-100000>