Please refer to https://community.oracle.com/thread/3687884 for details.

If you run the following code for a while, I noticed increasing memory consumption.

A heap analysis shows especially two classes which have thousands of instances (and keep growing):
1. java.lang.ref.WeakReference
2. javafx.beans.property.BooleanPropertyBase$Listener

After a heap analysis, it seems for me like something inside JavaFX is adding listeners to:

Platform.accessibilityActiveProperty()

but never removes them.



    import javafx.animation.Animation;
    import javafx.animation.KeyFrame;
    import javafx.animation.Timeline;
    import javafx.application.Application;
    import javafx.collections.FXCollections;
    import javafx.collections.ObservableList;
    import javafx.geometry.Insets;
    import javafx.scene.Scene;
    import javafx.scene.chart.NumberAxis;
    import javafx.scene.chart.StackedAreaChart;
    import javafx.scene.chart.XYChart;
    import javafx.scene.layout.Priority;
    import javafx.scene.layout.VBox;
    import javafx.stage.Stage;
    import javafx.util.Duration;
      
    public class TestApp4 extends Application {
        private static final int COUNT = 50;
      
        private final ObservableList<XYChart.Data<Number, Number>> data = FXCollections.observableArrayList();
      
        public static void main(String[] args) {
            launch();
        }
      
        @Override
        public void start(Stage stage) throws Exception {
      
            VBox root = new VBox();
            root.setPadding(new Insets(50, 50, 50, 50));
      
            NumberAxis timeAxis = new NumberAxis();
            timeAxis.setMinorTickVisible(false);
            timeAxis.setTickLabelsVisible(false);
            timeAxis.setLabel("t");
            NumberAxis memoryAxis = new NumberAxis();
            memoryAxis.setLabel("X");
            StackedAreaChart<Number, Number> stackedAreaChart = new StackedAreaChart<>(timeAxis, memoryAxis);
      
            final ObservableList<XYChart.Series<Number, Number>> data = FXCollections.observableArrayList();
              
            XYChart.Series<Number, Number> series = new XYChart.Series<>(this.data);
            data.add(series);
      
            updateSeries();
      
            stackedAreaChart.setData(data);
            stackedAreaChart.setAnimated(false);
            Timeline timeline = new Timeline(new KeyFrame(Duration.millis(100), actionEvent -> updateSeries()));
            timeline.setCycleCount(Animation.INDEFINITE);
            timeline.play();
      
            VBox.setVgrow(stackedAreaChart, Priority.ALWAYS);
      
            root.getChildren().add(stackedAreaChart);
      
            Scene scene = new Scene(root);
            stage.setScene(scene);
            stage.show();
        }
      
        private void updateSeries() {
            if (data.size() > COUNT) {
                data.remove(0);
            }
            for (XYChart.Data<Number, Number> data : this.data) {
                data.setXValue(data.getXValue().intValue() - 1);
            }
            data.add(new XYChart.Data<>(COUNT, Math.random()));
        }
    }