From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4AF15C82.8050804@domain.hid> Date: Wed, 04 Nov 2009 11:50:42 +0100 From: Gilles Chanteperdrix MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] bring down the system List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Schaal Cc: xenomai@xenomai.org, Peter Pastor Stefan Schaal wrote: > Sorry, I attached the wrong C-program in the previous posting .... > here is the corrected version: > > Hi, > > attached is a little C program that spawns off a task which runs a > heavy tiny math job. Despite my 8 processor machine, taking this one > task to 99% CPU load slows down the entire computer, often such that > there is no return except for a forced restart. > > I run the xenomai-head git, updated on Oct. 29 the last time, on a > i386 ubuntu system with kernel 2.6.29.5. > > Does anybody know what is going wrong here, i.e., am I not permitted > to take my CPUs to the max load? No, you can not do that. When a Xenomai task runs, Linux does not, and for your system to work correctly, Linux should run from time to time, so, the typical Xenomai setup is a periodic task which wakes up, does some job, and goes back to sleep, leaving some time for linux to run. -- Gilles