I'm playing a large map with over 250 planets and having over 6 hours in game.
I still have a bit of lag, but its way better then it was before.
Here is how iv done it.
1. run the game (I tried with game pause, it might work without)
2. go to processes and right click sins and go to set affinity
3. click each CPU individually and click ok
4. once done select all CPU's and click
Tell me if it work for u guys. Right now im running on CPU's 0,3,5, and 7