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From: Mark Hounschell <dmarkh@cfl.rr.com>
To: Anisha Kaul <born.rebel.83@gmail.com>
Cc: linux-rt-users@vger.kernel.org
Subject: Re: Hard real time in user space with preempt_rt patch
Date: Tue, 24 Apr 2012 04:57:32 -0400	[thread overview]
Message-ID: <4F966AFC.7070803@cfl.rr.com> (raw)
In-Reply-To: <CAM1yFZ_MLVNK8xPGg5Ad3suQh_AR18k6coyDqX9EurCkh9j9pg@mail.gmail.com>

On 04/24/2012 01:46 AM, Anisha Kaul wrote:
> From: https://rt.wiki.kernel.org/articles/f/r/e/Frequently_Asked_Questions_7407.html
>
>> Real-time only has impact on the kernel; Userspace does not notice the difference except for better real time behavior.
>
> Does it mean that if we write the applications in user space, they
> won't get the hard real time effect?
> The threads running in the userspace won't get the hard real time effect?
>

You use the term "hard real time". The RT patch set does not even come 
close to providing a "hard real time" environment, and isn't even 
attempting to. It does however provide user land applications a much better 
chance for a "soft real time" environment. The phrase you quot above just 
means the patches are applied to the kernel and there are no patches 
required for user land glibc or your application.

Regards
Mark

  parent reply	other threads:[~2012-04-24  8:57 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-04-24  5:46 Hard real time in user space with preempt_rt patch Anisha Kaul
2012-04-24  6:05 ` raz ben yehuda
2012-04-24  8:57 ` Mark Hounschell [this message]
     [not found]   ` <CAF-VNaq3bkC=LCB-Emsx20xTm-Vm1v3kduC5MpyXQA_GS6SOhg@mail.gmail.com>
2012-04-24  9:42     ` Mark Hounschell
2012-04-24 16:26       ` Sven-Thorsten Dietrich
2012-04-24 17:25         ` Mark Hounschell
2012-04-24 19:20           ` Lars Segerlund
2012-04-30 13:18             ` Esben Nielsen
2012-04-24 19:37       ` Armin Steinhoff
2012-04-24 11:36   ` John Kacur

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