The same thing happens after upgrading to iOS10 (with Iphone7) and xcode 8. I also export the instrument output as csv file and it's empty. No samples have been taken.
If no data is appearing then something isn't recording on the device quite right. You'll have to file a radar and include your host and device logs (along with all the information you provided here), so we can look into what is going on. Include exactly what actions you perform; the more detailed the easier it will be for us to reproduce the problem. Thanks.