Real-time performance stats

Amazon GameLift Streams collects performance stats during active stream sessions, measuring resource utilization every second. Use these stats to monitor your application's performance, identify resource bottlenecks, and optimize your streaming experience.

Performance stats include both application-level stats (CPU and memory utilization for your specific application) and system-level stats (CPU, memory, GPU, and VRAM utilization for the shared compute infrastructure).

You can receive performance stats in two ways:

Receive performance stats

Receive stats in real-time

To receive performance stats in your client application during an active session, set the SharedWithClient parameter to true when calling the StartStreamSession API. The Amazon GameLift Streams Web SDK provides a performanceStats callback that triggers whenever new stats arrive from the streaming session.

When initializing the Amazon GameLift Streams Web SDK, set clientConnection.performanceStats to a callback function that will receive performance stats.

const gls = new gameliftstreams.GameLiftStreams({
    videoElement: document.getElementById('streamVideoElement'),
    audioElement: document.getElementById('streamAudioElement'),
    inputConfiguration: {
        ...
    },
    clientConnection: {
        ...
        performanceStats: (perfStats) => {
            // Your callback logic here
            console.log('CPU: ' + perfStats.application.cpuNormalized);
            console.log('Memory: ' + perfStats.application.memoryMB + ' MB');
            console.log('GPU: ' + perfStats.system.gpuPercent + '%');
        },
    }
});

The callback receives a PerformanceStats object containing both application-level and system-level stats. For details on the interface structure, see the Amazon GameLift Streams Web SDK documentation on the Getting Started product page.

The Amazon GameLift Streams console also includes a built-in performance overlay when using the test stream feature, allowing you to monitor stats in real-time without any implementation work.

You can combine performance stats with WebRTC stats provided by the getVideoRTCStats() and getAudioRTCStats() functions in the Amazon GameLift Streams Web SDK. This combination provides a complete picture of streaming performance, including network stats, client frame rate, and resource utilization.

Receive stats post-session

Amazon GameLift Streams automatically collects performance stats during every stream session. When you export session files, the stats are included as stats/perf_stats_v1.csv in the exported ZIP file. This provides a complete record of all stats collected during the session for post-session analysis and debugging.

For more information about exporting session files, see Export stream session files.

Performance stats reference

The following table lists all performance stats collected by Amazon GameLift Streams. Application stats are specific to the current session, while shared system stats reflect the total utilization of the shared compute by sessions on multi-tenant stream classes.

The stat names listed in the following table are used as CSV column headers in the exported file. When receiving stats in real-time via the Amazon GameLift Streams Web SDK, these stats are available through the PerformanceStats interface with property names in camel case. For the exact interface structure and property names, see the Amazon GameLift Streams Web SDK API reference guide on the Getting Started product page.