Timing compilation when using threads

Is it possible to correctly measure compilation time when using Tasks on separate threads?

I have tried using the 1.11 @timed but get inconsistent timings for the compilation time.

I also don’t have a clear picture of what happens compilation-wise when one runs multiple tasks in parallel (multiple threads). Is the JIT-Compilation sequential? If it is is there some kind of lock mechanism that can stop another task while it waits for the compiler to be available?

Thanks