Xcode 8 hangs / unresponsive when opening storyboard

Question

I\'ve recently upgraded to Xcode 8 and updated my project to Swift 3. All worked fine for a little while. Storyboard loading has always been slow (even when still running Xcode

Answer 1

I had a similar problem: Interface Builder was slow to the point of being almost completely unresponsive.

I found that clearing my xcuserdata directory restored IB to normal speed.

Presumably some bad state had crept in that was causing the slowdown.

rm -rf Project.xcodeproj/xcuserdata/
rm -rf Project.xcworkspace/xcuserdata/