App performance and available metrics

For deeper analysis of your application performance, you need the Performance page of Trace. The primary purpose of the Performance page is to give you an overview of the performance of your app across the app’s entire install base.

The Trace performance page

You can check the performance of your apps in three distinct categories of metrics on the Performance page:

  • Application stability metrics: they show how reliable your app is.

  • Application responsiveness metrics: they show how quickly the app responds to user interaction.

  • Application consumption metrics: they show how much resources your app needs to run.

On the Performance page, you can check all these metrics, and break them down based on various properties, such as device type, operating system, network carrier, and so on. Read on to find out about the specific metrics, and how to take advantage of Trace’s analysis features.

Application stability metrics

Trace tracks three stability-related metrics:

  • Crashes: how many fatal errors the app has reported.

  • Errors: how many non-fatal errors have been generated.

  • Network errors: how many network request errors have been generated.

Application responsiveness metrics

Trace tracks three responsiveness-related metrics:

  • Cold start latency: how long the app takes to load when it is already running in the background.

  • Warm start latency: how long the app takes to be ready when returning to the foreground from a background state.

  • Network request latency: how long network requests made by the app take to complete.

Application consumption metrics

Trace tracks three metrics related to what an application consumes:

  • CPU: this the total CPU usage of the the app across all cores.

  • Memory: the total number of bytes of memory actively used by the app.

  • Request count: this is the number of network requests being made by the app.