Xcode 8 hangs / unresponsive when opening storyboard
<p>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 7) and was about the same 'slow' with Xcode 8. I always imagined this is because I'm on a older (late 2011) Macbook Pro. </p>

<p>But recently sometimes Xcode would just hang when I tried to open the storyboard. And since yesterday it's ALWAYS 'hanging'. Xcode becomes unresponsive and I have to Force Quit it.</p>

<p>In Activity Monitor I see Xcode using 102% CPU and Memory usage just keeps on growing (over 10GB if I let it).</p>

<p>Now I'm really stuck because when I open Xcode it immediately opens my project and wants to open the storyboard. I can't even change to a swift file. I'm not getting the window where I choose my project anymore. So, can't open my project anymore without Xcode turning unresponsive. Even when I double click another project to open Xcode it still tries to open my project (on the storyboard).</p>

<p>I've tried a number of things (based on SO threads I could find on similar problems with older versions of Xcode):</p>

<ul>
<li>Removed Xcode and removed contents of ˜/Library/Developer. Then reinstalled Xcode.</li>
<li>Removed contents of var/folders</li>
<li>Removed contents of derived data folder</li>
<li>Restart Macbook</li>
</ul>

<p>My next try is going to be to download the Xcode 8.1 beta. But really rather not do that. </p>

<p>Any other suggestions on things I could try?</p>

<p><strong>SMALL UPDATE:</strong>
Managed to clear the 'state' of Xcode where it opens my project by default and also opens it on the storyboard. Did this by:</p>

<ul>
<li>Removing the ~/Library/Saved Application State/com.apple.dt.Xcode.savedState folder (this will show the recent project window again on startup)</li>
<li>To also prevent the project from loading a specific file upon opening I went to the contents of .xcworkspace (in my project folder) and then removed /xcuserdata/myusername.xcuserdatad/UserInterfaceState.xcuserstate. Now the project opened without any file selected.</li>
</ul>

<p>Still... the main problem remains. When I click on my storyboard Xcode becomes unresponsive. </p>