What is the context switching time?
multithreading, operating-system, scheduling
Solution
It is really OS and situation dependent. You'll have to read about scheduling in general and about the specific threading technology you use: there is a nice list here.
When considering threads, the real wall-time intervals might change if other processes need CPU time, by that taking time from the process running the threads.
That being said, there are some nice C code samples to measure that time.
Problem
I have a doubt in context switching. In multi threading, when the context switching occurs, what will be the time between two context switches? Is it fixed time interval?