Hi , I am trying to observer loop rate of a while loop. Ideally it should take maximum of 2 ms to finish the cycle (500 Hz at least). And i would like to trace the loop rate using LTTng user space. whats the better way of doing it ..Just place one trace point at the start and one at the end ? or is there any library that i can take advantage of? while { trace_point (loop_start,...) // some thing trace_point(loop_end,....) } what do you think? -- Bhanu Kiran . Chaluvadi , Mechanical Engineering , National Institute of Technology,Warangal, India