From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <463AFA1C.9050609@domain.hid> Date: Fri, 04 May 2007 11:17:16 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <4639D724.5010702@domain.hid> <1178198991.29605.54.camel@domain.hid> <463AE79E.2090901@domain.hid> In-Reply-To: <463AE79E.2090901@domain.hid> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] Latency calculation and test List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Johan Borkhuis Cc: Xenomai-help@domain.hid Johan Borkhuis wrote: > When running latency at a higher priority than the cyclictest program > the max increases from around 4 to 8 usec when the cyclictest stops. But > when running the latency program at a lower priority (60, while > cylictest is running at 80 - 71) the maximum increases dramatically: > > RTT| 00:00:01 (periodic user-mode task, 100 us period, priority 60) > RTH|-----lat min|-----lat avg|-----lat max|-overrun|----lat best|---lat > worst > RTD| -0.096| 0.168| 3.843| 0| -0.096| > 6.510 > RTD| -0.072| 0.216| 23.135| 0| -0.096| > 23.135 > RTD| 0.048| 0.480| 14.270| 0| -0.096| > 23.135 > RTD| 0.048| 0.480| 14.030| 0| -0.096| > 23.135 > RTD| -0.096| 0.552| 613.741| 7| -0.096| > 613.741 > RTD| -0.096| 0.168| 7.975| 7| -0.096| > 613.741 > RTD| -0.072| 0.168| 3.843| 7| -0.096| > 613.741 > > If you want I can send you my version of the cyclictest program. What you can do is enabling the I-pipe tracer, see: http://www.xenomai.org/index.php/I-pipe:Tracer and run latency with the -f flag, to get a recording of the worst case scenario. -- Gilles Chanteperdrix