Diagnosing slowdowns?

[Hastati]

So, I've been having flights where despite rocking a solid 70 fps, things felt sluggish and time acceleration didn't seem to speed things up. I'm sure I'm having too much density from PWGC, but is there some way to diagnose exactly when I'm hitting this bottleneck besides "feel". Or am I actually insane and 70fps means its all running fine and dandy CPU wise?

[Juri_JS]

This slow down effect happens when too many AI planes are in a mission. AI ground objects are also having an effect, but it's only minor compared to aircraft.
It happens despite the recent change to dx11 so I guess it's mostly caused by the fact that AI calculations are using too much CPU performance. In my own scripted missions I try to limit the number of AI aircraft active at the same time to not more than 20 to avoid this effect.

[PatrickAWlson]

There are advanced configurations that limit the number of friendly or enemy flights and aircraft.  If I am flying fighters I prefer a an extra enemy flight or two.   If I am flying two seaters ... umm ... bombers ... I try to keep it more even.

 

PWCG has algorithms that determine which flights are closest to the player's path and keeping those.  If you follow the mission you will still often make contact even with relatively few flights.