If you wanted to measure the response time (the time between input and the first response by process, not necessarily the first output) how would you do it? Hopefully Ive defined resonse time correctly. Would this be the first context switch or first interrupt thats triggered, or is it the time it takes for a process to respond to an interupt? priya -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/