Xcode 6 Instruments freeze

Question

Profiling my iOS 8 app in Xcode 6 Instruments will run the app for about 5 seconds and then freeze. The profiler will still run after that point but the app is frozen and unusable. Happens on device and simulator and regardless of which profiler I'm using (timer, leaks, etc.)

Running the app from the debugger or an ad hoc build works fine. Profiling with iOS 7 works fine as well.

Any idea why this may be happening? Is Instruments broken?

Answer 1

I have a very large library that I work on and instruments hangs for me when trying to profile it. I found that I have to have DEBUG_INFORMATION_FORMAT set to DWARF with dSYM File at the app's build settings level.

Answer 2

For me I found out that Instruments was freezing when I started recording due to Xcode already running the application.

It's important for Xcode not to be running any processes when starting Instruments. If you do, Instruments will look like it is hanging.

You can push through the hang by going to Xcode and pressing "Continue Program Execution" on the bottom console toolbar of Xcode.

Answer 3

Same issue here:

Application hangs when profiling with instrument in XCode 6.0.1

Looks like if you remove all the NSLog statements it will fix it. For me this is happening only on iOS 8, i have no problems on iOS 7.

Answer 4

This was also happening to me on an iPod Touch + iOS 8.

Upgrading to 8.0.2 solved this problem for me.