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Date: Tue, 11 Mar 2008 11:26:00 -0600
From: "Chris Friesen" <cfriesen@nortel.com>
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To: Daniel Phillips <phillips@phunq.net>
CC: Lars Marowsky-Bree <lmb@suse.de>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Grzegorz Kulewski <kangur@polcom.net>, linux-kernel@vger.kernel.org
Subject: Re: [ANNOUNCE] Ramback: faster than a speeding bullet
References: <200803092346.17556.phillips@phunq.net> <200803110414.40954.phillips@phunq.net> <20080311112329.GR1581@marowsky-bree.de> <200803110450.19390.phillips@phunq.net>
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Daniel Phillips wrote:
> On Tuesday 11 March 2008 04:23, Lars Marowsky-Bree wrote:
> 
>>If I always assume a reliable shutdown - UPS protected, no crashes, etc
>>- you're right, but at least my real world has other failure scenarios
>>as well. In fact, the most common reason for unorderly shutdowns are
>>kernel crashes, not power failures in my experience.
> 
> 
> What are you doing to your kernel?

<snip>

> Honestly, I have never seen a machine running
> Linux 2.6 crash due to a software flaw, except when I caused it
> myself.  I suspect the Linux kernel has a better MTBF than a hard
> disk.

I have experienced many 2.6 crashes due to software flaws.  Hung 
processes leading to watchdog timeouts, bad kernel pointers, kernel 
deadlock, etc.

When designing for reliable embedded systems it's not enough to handwave 
away the possibility of software flaws.

Chris

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