All Xcodes updates have been "a problem" for me. The last one was 150MBs and took about 20mins to download (150MBs!? It's a university network.). It think the server for Xcode is one of their 2014 Mac mini's. Then it took about 25 minutes to install. The install, not download, times just kept bouncing all over the place. Xcode updates are rarely ever fast for me.I've been having trouble updating Xcode all morning. And this isn't the first time. The App Store app has always been a bit unstable for me, but recently it has gotten much worse. Updates take forever to install, and then fail with a vague "unknown error occurred" message. I finally filed a bug about it yesterday.