From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Sergio Ruocco <ruocco@disco.unimib.it>
Cc: Pradyumna Sampath <pradysam@gmail.com>,
Jeff Angielski <jeff@theptrgroup.com>,
Robert Schwebel <r.schwebel@pengutronix.de>,
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: Wed, 15 Sep 2010 07:58:12 -0700 [thread overview]
Message-ID: <20100915145812.GB2544@linux.vnet.ibm.com> (raw)
In-Reply-To: <4C90C093.4070607@disco.unimib.it>
On Wed, Sep 15, 2010 at 02:48:19PM +0200, Sergio Ruocco wrote:
> Pradyumna Sampath wrote:
> > I agree. Hard, soft ... far too qualitative for a discussion like
> > this. Numbers, test cases and applications determine different
> > meanings of these words.
>
> Right. Hard and Soft realtime discussions end up always in useless
> infinite loops. The *applications*' *requirements* are hard or soft.
>
> These requirements reflect in the OS, the CPU, the IO devices, and more
> typically a convolution of all of them, depending on what the
> application does, i.e., the actual sequence of computations, OS
> syscalls, IO operations and so on...
I did a Linux Journal article on this topic a few years ago:
http://www.linuxjournal.com/article/9361
I also did a portion of a short course on this topic last year:
http://www.rdrop.com/users/paulmck/scalability/paper/ACACES2009/4-LKRT.2009.07.16a.pdf
http://www.rdrop.com/users/paulmck/scalability/paper/ACACES2009/5-AppRT.2009.07.17b.pdf
Thanx, Paul
> > Top copy a phrase from one of the presentations from dresden.
>
> Which presentation? I am curious to read it.
>
> > Real-time need not always be real fast.
>
> "Real fast is not real-time" is a catchy phrase which comes from this
> very old workshop:
>
> http://www.langston.com/Papers/uk.pdf
>
> I used it to motivate an investigation in the real-time properties of a
> "real fast" microkernel:
>
> http://www.hindawi.com/journals/es/2008/234710.abs.html
>
> Have fun!
>
> Sergio
> --
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next prev parent reply other threads:[~2010-09-15 14:58 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
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 [this message]
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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