Before profiling, you can set preferences that change how the profiling performs and what should be recorded. These preferences control the accuracy and amount of data collected at the expense of potential performance impact.
To open the Profiling preferences, select Detox Instruments ➔ Preferences, and select the Profiling tab.
The Sampling frequency preference configures how many samples should be collected every second. The more samples collected, the more accurate the profiling, at some expense of performance.
It is recommended to start with the default value and only increase sampling frequency if necessary.
The Record performance preference controls whether performance samples are collected during profiling. Disable this if you want to focus on other instruments, such as network, events or React Native profiling.
The Record thread information preference controls whether any thread information is recorded during profiling. Recording thread information can provide additional performance metrics per thread. Normally, recording thread information is not an expensive operation and should be enabled unless absolutely not needed.
The Collect stack traces preference enables the recording of the stack trace of the heaviest thread. This provides code symbol information for additional debugging purposes. This is a relatively inexpensive operation, but depending on the sampling frequency, may have a slight performance cost.
The Symbolicate stack traces preference enables the runtime symbolication of symbols collected in stack traces. This further assists development by creating human-readable symbols. This is a relatively inexpensive operation, but depending on the sampling frequency, may have a slight performance cost.
The Collect open file names preference enables the collection of names of files open in the app at the time of sampling. This is a relatively inexpensive operation, but depending on the sampling frequency, may have a slight performance cost.
The Record network preference controls whether any network traffic is recorded, including headers and data. Depending on your app's activity, this can take a small-to-moderate toll on performance. If network recording is not necessary, you can turn this preference off to save performance.
The Record localhost network preference extends the network recording to localhost connections as well. Depending on your app's activity, this may introduce a lot of unwanted noise. Enable if you need to profile or debug localhost connections.
The Disable network cache preference controls whether network cache should be disabled for requests the app makes while recording.
The Record events preference controls whether any events are recorded during profiling.
The Ignored Categories button presents the Ignored Events Categories sheet.
In this screen, you can add Events categories that will be ignored when recording. Use this to save performance and lower clutter. For an in-depth look at the Events instrument, see Events Instrument.
The Record app activity preference controls whether activity events are recorded during profiling.
For an in-depth look at the Events instrument, see Activity Instrument.
The Collect log output preference enables the recording of your app's log output. This can be very useful for cross-referencing your debug log output with profiling samples of your app. This is an inexpensive operation, but depending on the log output amount, may have a slight performance cost.
The Profile React Native (if available) preference controls the React Native profiling systems in Detox Instruments and its Profiler framework. These systems provide information such as JavaScript thread performance, bridge calls and bridge data, which can be very helpful when debugging apps with React Native usage.
The Record async storage data preference controls whether React Native async storage data is recorded in conjunction to async storage metrics. Depending on your app's activity, this can take a small-to-moderate toll on performance. If async storage data recording is not necessary, you can turn this preference off to save performance.
The Record bridge data preference controls whether React Native bridge data is recorded during profiling. Depending on your app's activity, this can take a small-to-moderate toll on performance. If bridge data recording is not necessary, you can turn this preference off to save performance.
The Record timers as activity preference controls whether React Native timers, created in JavaScript using setTimeout(), should be recorded as activity and displayed in the Activity instrument. This preference requires that the detox-instruments-react-native-utils package be installed in your React Native app. For information on installing the package, see Events API Reference for React Native / JavaScript.
The Record internal React Native activity preference controls whether internal React Native activity is recorded. Record this information when you want to have insight on the internal working and performance of React Native.
The Time limit preference sets a hard time limit on recording duration. You can set the value in seconds, minutes or hours. The default is 2 minutes.
The App launch profiling preference sets the duration, in seconds, to profile app launches. The default is 15 seconds.
The Restore Defaults button resets all profiling preferences to their default value. These defaults may change from time to time, depending on development and feedback considerations.