Performance is one of the most important things that you should take care of in your app. Your users need to use your app smoothly with no interruption or hanging. They have something to do, and they have to do it fast. When you develop your application, you develop it for a platform, not for a specific device. For example, you develop an iOS application, which will run on different types of devices with different CPU capabilities. That's why, measuring your app performance is very important, so you can find the areas that need optimization.
In these measurements, we will not write any code. So, you can pick any Xcode project you have to run these experiments on.
First, we will try to measure the CPU usage of an app to see how our app uses the multiple cores/threads that we have.
Open the Xcode project, and click on Profile as we did in the preceding recipe.
Choose Time Profiler from the list of instruments:
Choose the device/simulator and the app from the...