From: Jeff Angielski <jeff@theptrgroup.com>
To: Robert Schwebel <r.schwebel@pengutronix.de>
Cc: Raz <raziebe@gmail.com>,
"Nikita V. Youshchenko" <yoush@cs.msu.su>,
linux-rt-users <linux-rt-users@vger.kernel.org>
Subject: Re: preempt rt in commercial use
Date: Tue, 14 Sep 2010 10:21:52 -0400 [thread overview]
Message-ID: <4C8F8500.5070002@theptrgroup.com> (raw)
In-Reply-To: <20100914094411.GB10841@pengutronix.de>
On 09/14/2010 05:44 AM, Robert Schwebel wrote:
> On Tue, Sep 14, 2010 at 11:24:21AM +0200, Raz wrote:
>> anyone can say preempt rt is hard real time?
>
> Hard realtime has something to do with how you define "missing the
> deadline". If somebody cuts the cable of your roboter controller in the
> factory hall, the system misses the deadline. So it is all about
> probabilities: hard realtime systems have a very, very low probability
> of missing the deadline. However, in real life systems, it is> 0%.
>
> So yes, if you talk about real world, it is hard realtime.
No. Preempt rt it's not hard realtime.
But most people/companies who think they need hard realtime really
don't. They can live with soft realtime and have a really low
probability of missing deadlines and having long latencies. For these
people, the preempt rt is adequate.
--
Jeff Angielski
The PTR Group
www.theptrgroup.com
next prev parent reply other threads:[~2010-09-14 14:32 UTC|newest]
Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-14 8:10 preempt rt in commercial use Raz
2010-09-14 9:04 ` Rolando Martins
2010-09-14 9:10 ` Raz
2010-09-14 9:20 ` Rolando Martins
2010-09-14 9:17 ` Nikita V. Youshchenko
2010-09-14 9:24 ` Raz
2010-09-14 9:44 ` Robert Schwebel
2010-09-14 12:16 ` Armin Steinhoff
2010-09-14 13:04 ` Daniel James
2010-09-14 13:08 ` Pradyumna Sampath
2010-09-14 22:11 ` Nivedita Singhvi
2010-09-14 13:09 ` Klaas van Gend
2010-09-14 13:17 ` David Kastrup
2010-09-14 13:37 ` Darcy Watkins
2010-09-14 13:58 ` Patrice Kadionik
2010-09-14 14:21 ` Jeff Angielski [this message]
2010-09-14 14:30 ` Nikita V. Youshchenko
2010-09-14 14:49 ` Jeff Angielski
2010-09-14 22:20 ` Nivedita Singhvi
2010-09-15 7:48 ` Armin Steinhoff
2010-09-15 14:09 ` Nivedita Singhvi
2010-09-15 14:45 ` Pradyumna Sampath
2010-09-16 10:17 ` Daniel James
2010-09-16 10:35 ` Pradyumna Sampath
2010-09-16 15:19 ` Raz
2010-09-15 15:38 ` David Kastrup
2010-09-15 16:02 ` Nivedita Singhvi
2010-09-15 16:20 ` David Kastrup
2010-09-16 0:44 ` Steven Rostedt
2010-09-16 15:27 ` Nivedita Singhvi
2010-09-16 17:30 ` Steven Rostedt
2010-09-16 19:27 ` Armin Steinhoff
2010-09-16 19:38 ` Steven Rostedt
2010-09-15 13:33 ` Thomas Gleixner
2010-09-14 14:44 ` Pradyumna Sampath
2010-09-15 12:48 ` Sergio Ruocco
2010-09-15 12:53 ` Pradyumna Sampath
2010-09-15 14:58 ` Paul E. McKenney
2010-09-15 16:27 ` Sven-Thorsten Dietrich
2010-09-16 0:49 ` Steven Rostedt
2010-09-16 5:06 ` David Kastrup
2010-09-14 14:56 ` Armin Steinhoff
2010-09-14 15:42 ` Patrice Kadionik
2010-09-14 17:38 ` Gregory Haskins
2010-09-14 22:09 ` Nivedita Singhvi
2010-09-15 6:22 ` Patrice Kadionik
[not found] ` <4C90CF71.2050205@us.ibm.com>
2010-09-15 13:56 ` Patrice Kadionik
2010-09-15 14:08 ` Steven Rostedt
2010-09-14 10:06 ` Klaas van Gend
2010-09-14 11:00 ` David Kastrup
2010-09-14 9:28 ` Pradyumna Sampath
2010-09-14 14:13 ` Reagan Thomas
2010-09-15 7:09 ` AW: " Lukas Redlinger
2010-09-15 3:38 ` jordan
2010-09-15 8:59 ` Klaas van Gend
2010-09-15 11:03 ` TinxCore and PREEMPT_RT Armin Steinhoff
2010-09-16 9:38 ` Armin Steinhoff
2010-09-16 10:18 ` David Kastrup
2010-09-16 11:25 ` Mike Galbraith
2010-09-16 11:51 ` Armin Steinhoff
2010-09-15 14:03 ` preempt rt in commercial use Nivedita Singhvi
2010-09-15 17:29 ` Reagan Thomas
2010-09-16 10:39 ` Daniel James
2010-09-16 20:47 ` jordan
2010-09-16 10:07 ` Daniel James
2010-09-16 20:37 ` jordan
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