Use Flashlight to Monitor Activity

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Prerequisites

1. Install the Vega SDK
2. Install yarn

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Install Flashlight

1. Download Flashlight:
2. Extract to flashlight directory:
   unzip flashlight-kepler-becb05f.zip -d ~/flashlight
   
3. Build using yarn:
   cd ~/flashlight/flashlight-private-kepler-secret
   yarn
   yarn build
   

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Run Flashlight

1. Launch your sideloaded app on Fire TV Stick or Vega Virtual Device.
2. Navigate to Flashlight directory:
   cd ~/flashlight/flashlight-private-kepler-secret
   
3. Run measure command to start Flashlight web interface.
   • For Vega Virtual Device:
     PLATFORM=keplersimulator node packages/commands/measure/dist/server/bin.js measure
     
   • For Fire TV Stick:
     PLATFORM=keplerdevice node packages/commands/measure/dist/server/bin.js measure
     
   The terminal prints a local URL (for example, http://localhost:3000). Open it in your browser to load the Flashlight web interface.
4. In the Flashlight web interface, do the following:
   • Select the “Auto Detect” to find your app’s package ID.
   • Select the “Start Measuring” to begin monitoring.
   Flashlight begins displaying live CPU and memory data for your app, confirming that monitoring is active.

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Watch how to use Flashlight

1. Build, sideload, and launch VegaVideoApp on Fire TV.
2. Use Flashlight to monitor VegaVideoApp’s live performance.

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Related topics

• Monitor and Record Memory
• Monitor CPU Usage