Xcode 9 - High CPU usage - Fan max speed

Question

Ever since I upgraded to Xcode 9, my fan goes crazy when I'm working on Xcode. This is especially happening when I use Storyboards and Interface Builder.

Xcode sometimes takes up to 100% of the CPU and the process named "Interface Builder Cocoa Touch Tool" is also very greedy.

I read here and there that other people have had similar issues but I was wondering if anyone found a solution to this considering it's most likely a Xcode bug.

Things I've tried:

• Unplugging my second screen: no effect
• Rebooting Xcode: no effect
• Rebooting Mac: no effect
• Cleaning Derived Data folder: no effect
• Cleaning project: no effect
• Opening only 1x project at the time (annoying): a bit better but still not great

Did anyone find a solution to this issue?

Mac Config:

• MacBook Pro (Retina, 15-inch, Mid 2014)
• Processor: 2,5 GHz Intel Core i7
• Memory: 16 GB 1600 MHz DDR3
• Graphics: NVIDIA GeForce GT 750M 2048 MB Intel Iris Pro 1536 MB

Xcode version: 9.0 (9A235)

Answer 1

Open your xibs/storyboards and turn off “Editor / Automatically refresh views”.

The issue is caused by Xcode continually rebuilding your project to update things like custom IB_DESIGNABLE views.

Trigger it manually via Editor > Refresh All views