From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4A2669AA.60600@domain.hid> Date: Wed, 03 Jun 2009 14:16:42 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <103585745.148571244020625685.JavaMail.root@domain.hid> In-Reply-To: <103585745.148571244020625685.JavaMail.root@domain.hid> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] How to chose between xenomai and preempt RT List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Adrien LECOINTRE Cc: xenomai@xenomai.org Adrien LECOINTRE wrote: > I read a lot of things about PREEMPT_RT not providing hard real-time > but I coudn't find any test case which shows that. My loads are > probably not good enough but it shouldn't be so difficult to find a > way to cause a significant latency on a supposed non-hard-real-time > OS. I can not leave this unanswered. This is a question of code coverage. Only when you have tested most of the code paths in the Linux kernel can you state that you have made a proper test. The only way to do this found so far (by the preempt_rt people, I believe) is to run LTP, the Linux Testing Project. And even though you do not test all the drivers in your system (except the most current ones such as ethernet and ATA). -- Gilles.