Hi Prabhu, On 21 October 2010 23:56, Prabhu nath <gprabhunath@xxxxxxxxx> wrote: > Dear All, > > > There is a time difference t between the time t1-at which the pending signal > is set and the time t2-at which exact signal handler is executed. > > Question: I need to calculate the time difference between t1 and t2. Have you set a virtual time interrupt (ITIMER_VIRTUAL) or real timer interrupt (ITIMER_REAL)? There are two components here: scheduler latency and the timer interrupt latency. Both add up to the latency perceived by the userspace program. Which one do you want to measure? If you're interested in the end latency and if you've set a ITIMER_REAL timer, it's pretty easy to measure the latency upto some precision. Before setting the timer, note the 'start' real time using gettimeofday. After the timer handler (after time interval dt) fires, note the real time 'end'. (end-start) - dt should be the required latency. -- Vimal -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
