Am 14.09.2012 um 06:30 schrieb Kent A. Reed: > With the RT PREEMPT system, this board gives lousy results even running > headless. Using latency-test, for some minutes I see the base (25us) > thread showing a max latency of anywhere from 25us to 40us and the servo > (1000us) thread 40us to 50us. Then, the servo thread pops a bit and the > base thread pops a lot, to about 110us. At the same time, the kernel > throws three lines to the console > > "ERROR: Missed scheduling deadline for task 0 [nnnn times] > "Now is xxxxx.xxx, deadline is xxxxx.xxx > "Absolute number of pagefaults in realtime context: 1030"
I guess this could be mitigated by pre-page faulting all RT code into memory this example deals with the issue: https://rt.wiki.kernel.org/index.php/Threaded_RT-application_with_memory_locking_and_stack_handling_example Lars: you also hinted at that - how did you do it? -m ------------------------------------------------------------------------------ Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
