The chart’s x-axis is a timeline of events (timeseries).
The data plotted in the y-axis all has a timestamp of
when the data was collected. In other words,
it shows the polled state (capacity, used, external,
RSS (resident set size), and GC (garbage collection))
of the memory every 500 ms. This helps provide a live
appearance on the state of the memory as the application is running.

Clicking the Legend button displays the
collected measurements, symbols, and colors
used to display the data.

The Memory Size Scale y-axis automatically
adjusts to the range of data collected in the
current visible chart range.

The quantities plotted on the y-axis are as follows:

Objects (Dart and Flutter objects) in the heap.