1# @ohos.arkui.performanceMonitor (Performance Monitor) 2 3The **performanceMonitor** module provides APIs for performance monitoring indicators: response delay, completion delay, and frame loss rate. 4 5> **NOTE** 6> 7> The APIs of this module are supported since API version 10. Updates will be marked with a superscript to indicate their earliest API version. 8> 9> The APIs provided by this module are system APIs. 10 11 12## Modules to Import 13 14```ts 15import performanceMonitor from '@ohos.arkui.performanceMonitor'; 16``` 17 18 19## ActionType 20 21Enumerates types of actions that trigger user scenes. 22 23**System capability**: SystemCapability.ArkUI.ArkUI.Full 24 25| Name| Value| Description| 26| -- | -- | -- | 27| LAST_DOWN | 0 | Pressing against the screen. | 28| LAST_UP | 1 | Lifting a finger off the screen.| 29| FIRST_MOVE | 2 | First swiping on the screen.| 30 31 32## performanceMonitor.begin 33 34begin(scene: string, startInputType: ActionType, note?: string): void 35 36Starts a user scene. 37 38 39**System capability**: SystemCapability.ArkUI.ArkUI.Full 40 41**Parameters** 42 43| Name| Type| Mandatory| Description| 44| -- | -- | -- | -- | 45| scene | string | Yes| User scene ID.| 46| startInputType | [ActionType](#actiontype)| Yes| Type of action that triggers the user scene.| 47| note | string| No| Important information about the user scene.| 48 49**Example** 50 ```ts 51performanceMonitor.begin("LAUNCHER_APP_LAUNCH_FROM_ICON", performanceMonitor.ActionType.LAST_UP, "APP_START_BEGIN"); 52 ``` 53 54 55## performanceMonitor.end 56 57end(scene: string): void 58 59Ends a user scene. 60 61**System capability**: SystemCapability.ArkUI.ArkUI.Full 62 63**Parameters** 64| Name| Type| Mandatory| Description| 65| -- | -- | -- | -- | 66| scene | string | Yes| User scene ID, which corresponds to that in **begin**.| 67 68**Example** 69 ```ts 70performanceMonitor.end("LAUNCHER_APP_LAUNCH_FROM_ICON"); 71 ``` 72