How to get the average/max process scheduling latency

Hi, I would like to retrieve the average latency between 2 schedulings of an application. The purpose is to model the service time of the application (ie. How fast it can empty the TCP buffer). I could not find an answer yet. I've found that on latest kernel latency is on average around 3us with a max at 64us (I consider a moderate load). Is that correct ? Regards Matt