In Xcode 9 there is new option to Run multiple simulators at the same time. When I tried launch second simulator its forced to stop the running instance. Is it possible to debug in multiple simulators without stopping the already running simulator's process. I want to debug with both simulators at the same time like real device.
On the simulator, you must choose a new device from Hardware > Devices. The new instance will starts.
Then, choose your model on Xcode.
https://help.apple.com/simulator/mac/9.0/index.html?localePath=en.lproj#/devd856f9e4c
More description available here.
NOTE : Till now , its not possible to debug in both simulators at the same time. You can only check UI , if you add a new simulator the instance of previous will be ended.