roland Tollenaar wrote: > Hi > > I need to be educated a bit here if you don;t mind. > > arming up... > RTT| 00:00:01 (periodic user-mode task, 1000 us period, priority 99) > RTH|-----lat min|-----lat avg|-----lat max|-overrun|----lat best|---lat worst > RTD| 29.333| 29.333| 31.847| 0| 29.333| 31.847 > RTD| 29.333| 29.333| 35.199| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 33.523| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 32.685| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 34.361| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 33.523| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 33.523| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 34.361| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 32.685| 0| 29.333| 35.199 > RTD| 29.333| 29.333| 34.361| 0| 29.333| 35.199 > RTD| 29.333| 31.847| 201.142| 0| 29.333| 201.142 > RTD| 29.333| 59.504| 205.333| 0| 29.333| 205.333 > RTD| 29.333| 65.371| 201.142| 0| 29.333| 205.333 > RTD| 29.333| 68.723| 201.980| 0| 29.333| 205.333 > RTD| 29.333| 64.533| 201.142| 0| 29.333| 205.333 > RTD| 29.333| 65.371| 204.495| 0| 29.333| 205.333 > RTD| 29.333| 52.799| 201.142| 0| 29.333| 205.333 > RTD| 29.333| 65.371| 204.495| 0| 29.333| 205.333 > RTD| 29.333| 35.199| 201.142| 0| 29.333| 205.333 > RTD| 29.333| 29.333| 34.361| 0| 29.333| 205.333 > RTD| 29.333| 29.333| 33.523| 0| 29.333| 205.333 > ---|------------|------------|------------|--------|------------------------- > > > What you see above (up to where max latecy jumps to 200) is the > behavior while my application is running but the node (rotary encoder) > is not moving so not sending any position signals. The moment I start > turning the encoder shaft the jump takes place. > > What does output of latency mean? Is the above result simply stating > that I have a crappy hardware structure and will never be able to > achieve better latency or does it tell me there is something wrong > with my application?
Enable the I-pipe tracer, recompile your kernel, set /proc/ipipe/trace/back_trace_points to a larger value, and run latency with the -f flag. Show us the contents of /proc/ipipe/trace/frozen, and we may be able to give you an answer. For more details on the I-pipe tracer, see: http://www.xenomai.org/index.php/I-pipe:Tracer -- Gilles Chanteperdrix _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
