How to understand performance problems in "Native or Optimized code" when using DotTrace Performance

Question

I am using DotTrace Performance (v 5.5.4) on my web application. I am trying to optimize the page load time after cold starting the MVC 5 application. Looking at the main thread on the snapshot, it seems like majority of the work is being done in "Native or Optimized code". Thats seems a little too generic and is not really helpful. What does that really mean and how do I dig into it further?

Note : I found a similar post on the jetbrains forum but there did not seem to be any resolution posted there either.

Answer 1

Probably it is JITting time there. Does the second opening of same page also takes much time? Maybe you have opportunity to use dotTrace 6.1+? It has Timeline mode that can show thread states, distribution by File I/O, Jit, GC times on any time range. It might reveal the underneath native activity on that thread.