Performance metrics

Startup time to the first frame
    
      Check the time when
WidgetsBinding.instance.firstFrameRasterized 
is true.
      See the
perf dashboard.

Frame buildDuration, rasterDuration, and totalSpan
    
      See FrameTiming
in the API docs.

Statistics of frame buildDuration (*_frame_build_time_millis)
    
      We recommend monitoring four stats: average, 90th percentile, 99th
percentile, and worst frame build time.
      See, for example, metrics for the 
flutter_gallery__transition_perf test.

Statistics of frame rasterDuration (*_frame_build_time_millis)
    
      We recommend monitoring four stats: average, 90th percentile, 99th
percentile, and worst frame build time.
      See, for example, metrics for the 
flutter_gallery__transition_perf test.