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Date: Wed, 28 Jul 2004 13:46:03 -0700
To: Lee Revell <rlrevell@joe-job.com>
Cc: Bill Huey <bhuey@lnxw.com>, karim@opersys.com,
       Scott Wood <scott@timesys.com>, Ingo Molnar <mingo@elte.hu>,
       "La Monte H.P. Yarroll" <piggy@timesys.com>,
       Manas Saksena <manas.saksena@timesys.com>,
       Philippe Gerum <rpm@xenomai.org>,
       linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [patch] IRQ threads
Message-ID: <20040728204603.GA7106@nietzsche.lynx.com>
References: <20040727225040.GA4370@yoda.timesys> <4107CA18.4060204@opersys.com> <1091039327.747.26.camel@mindpipe> <4107FA93.3030801@opersys.com> <1091043218.766.10.camel@mindpipe> <20040728202107.GA6952@nietzsche.lynx.com> <1091047369.791.35.camel@mindpipe>
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From: Bill Huey (hui) <bhuey@lnxw.com>
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On Wed, Jul 28, 2004 at 04:42:51PM -0400, Lee Revell wrote:
> As I understand it there will still be a place for the current hard-RT
> Linux solutions, because even if I can get five nines latency better
> than N, this is not good enough for hard RT, as you need to be able to
> mathematically demonstrate that you can *never* miss a deadline.
> 
> Or are you saying that the latest developments in the stock kernel make
> this possible?

Not quite with this thread and in this stage of development, but this is
quite possible if certain concurrency problems are solved in Linux. RCU is
a potential pain as well as other things. BSD/OS-FreeBSD-current are not
new to this kind of conversion, so this is certainly very possible with
very finite software engineering problems to solve. 

Scary ain't it ? It makes me wonder some times.

bill