It was working great for a while, but for some reason today, it is a lot less reliable: Often the "Capture GPU" option is grayed out, and when it does work, it is stuck with Xcode showing "Debugging GPU Workload." And things like the "Memory" breakdown, which is typically very useful, cannot be opened to see details. How can I diagnose this problem? Thanks.

We're working on a graphics-intensive game for iOS, and we are very concerned about battery drain and thermals. While it's hard to control the user's conditions (ambient temperature, insulating case, battery lifecycle, etc.), we know we can't ignore these issues and we want to make sure we're in line with general expectations. We have found it very challenging to get consistent measurements for the different thermal conditions, such as how long it takes to reach T2 from T1. Room temperature has huge effects. So, we thought a more consistent metric may be battery drain: how much % is used after 15 minutes of play, for example? If we were to focus on this as our metric, would this also take care of heat generation? Specifically, if we make a change and do an A/B test, and found that battery drain was the same, can we safely infer that our heat behavior is also the same? Or, if we did another AB test and found that it drained the battery faster, can we assume the change would also increase phone temperature faster? We have of course observed oddness with the battery percentage, but with some caveats in mind, it seems like something we can measure much more easily and consistently. Any insights in this would be much appreciated!

I have QA doing testing with Xcode performance state, but to help catch human error, I'd like to abort the test if GPU Performance state condition is not actually active, or is wrong. Is there a way I can do that, from the iOS app itself? It seems like it doesn't not set any environment variable or anything to indicate it is active.