I'm experiencing the same and filed a Feedback report. It's a very annoying warning that floods the console.

I'm also experiencing this issue. The CPU is slowly moving up about 1% every second, until it reaches >250%. Disabling both Main Thread Checker and Thread Performance Checker in the Scheme's Run target Diagnostics tab will resolve it.

I finally found the solution: [quote='786373022, herbertv, /thread/747784?answerId=786373022#786373022, /profile/herbertv'] On your iPhone: Go to Settings, then tap General. Tap Transfer or Reset [Device]. Tap Reset, then tap Reset Location & Privacy. Now the link between your iPhone and Xcode is removed / untrusted. Make sure you have your apple watch selected as active watch in the iPhone Watch app. Now open Xcode and connect the iPhone with USB cable. The "do you want to trust this device" alert should pop-up on your iPhone again. Select Trust device. Give it a bit of time, and once your iPhone becomes available as destination, your AW should also pop-up. At least this worked for me. [/quote]

Same issue here, very annoying as it floods the logs. No idea what is causing it.

Same problem here.

I'm experiencing the same issue in my app. Is there a solution/workaround?