问题
After updating my gadgets with iOS 9 I've tried to update Xcode to Xcode 7 on my Mac through the App Store, but updating is too slow while speedtest.net shows that my download speed is about 30 mbps. What to do?
回答1:
You can always download the dmg for new or earlier versions of Xcode (or any other developer tool for that matter) from this link provided by Apple for iOS and Mac developers.
回答2:
I had the same issue downloading Xcode 7.2. The download was drastically slow compared to my internet download speed. Try this fix it worked for me:
I noticed a huge increase in the download speed from 1d to 1h. Maybe it has to do with apple finding the nearest server according to your account location or some routing magic.
回答3:
Strangely enough, the fix for me was downloading the .xip file in Safari. It seems that the download was capped to 100KB/s on Google Chrome, using Safari there seemed to be no network throttle.
回答4:
In my case, I was running out of Disk space on main partition as I have partitions on my Hard Drive and all these partitions act as different drives. By sparing a couple of GBs, the download speed got to normal.
回答5:
I had the same issue, the update ran forever and never finished. I uninstalled Xcode and when i tried to install it again it said I needed the OS X 10.12 at least.
So i upgraded OS X and then installed Xcode 8.3
I wish the update told me that before i wasted 2 days trying to figure it out.. Hope it helps!
回答6:
If you're downloading from your office network, try switching to another. This might be happening because of the security measures, an internal DNS resolver as I am told, or a firewall; so it's hard to tell what's happening but switching to the "guest" network allowed me to download it pretty fast in my case.
Although it's unlikely that your problem is caused by this, but you can check the Apple systems status on this page.
来源：https://stackoverflow.com/questions/32665958/xcode-updating-is-extremely-slow