From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4FBBBA25.5010308@mind.be> Date: Tue, 22 May 2012 18:09:09 +0200 From: Arnout Vandecappelle MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: [Xenomai] CPU occupation without context switches? List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: xenomai@xenomai.org Hoi, After a few minutes of running my application, I see this: # cat /proc/xenomai/stat CPU PID MSW CSW PF STAT %CPU NAME 1 828 22 65 0 00300182 9.8 bench_RTnet_scope_thread_loop 1 839 2 46627538 0 00300186 53.8 bench_RTnet ... i.e. the bench_RTnet_scope_thread_loop takes 10% CPU but no context switches. How is this possible? I've looked at the source code and can't find an explanation: when the exectime accounting is updated, the csw is incremented as well (in __xnpod_schedule()). I'm asking because I can't find a reason why this thread should occupy 10% of the CPU, so I'm wondering if there's something wrong with the accounting instead. BTW this is on Xenomai 2.5.6, on an SMP x86 with affinity=0x01. Regards, Arnout -- Arnout Vandecappelle arnout at mind be Senior Embedded Software Architect +32-16-286540 Essensium/Mind http://www.mind.be G.Geenslaan 9, 3001 Leuven, Belgium BE 872 984 063 RPR Leuven LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle GPG fingerprint: 7CB5 E4CC 6C2E EFD4 6E3D A754 F963 ECAB 2450 2F1F