[Home](./index.md) > [@firebase/performance](./performance.md) ## performance package Firebase Performance Monitoring ## Functions | Function | Description | | --- | --- | | [getPerformance(app)](./performance.getperformance.md) | Returns a FirebasePerformance instance for the given app. | | [initializePerformance(app, settings)](./performance.initializeperformance.md) | Returns a FirebasePerformance instance for the given app. Can only be called once. | | [trace(performance, name)](./performance.trace.md) | Returns a new PerformanceTrace instance. | ## Interfaces | Interface | Description | | --- | --- | | [FirebasePerformance](./performance.firebaseperformance.md) | The Firebase Performance Monitoring service interface. | | [PerformanceSettings](./performance.performancesettings.md) | Defines configuration options for the Performance Monitoring SDK. | | [PerformanceTrace](./performance.performancetrace.md) | The interface representing a Trace. |