JS code inside qml runs so slowly for generating a series

Question

I'm currently working on a line chart and trying to generate a random series of points for it. I wrote some js codes in order to generate a random series for my line chart but when I want to generate 17000 points or even more , my code runs so slow and it takes about 1 minute to generate the series for my line chart. I don't know if I'm writing inefficiently in js or should I write it in a separate thread ?

ChartView {
            id: centralLineChartView
            legend.visible: false
            antialiasing: true
            anchors.fill: parent
            axes: [
                ValuesAxis {
                    id: xAxis
                    min: 0
                    max: 1000
                } ,
                ValuesAxis {
                    id: yAxis
                    min: -130
                    max: 10
                }
            ]

            Component.onCompleted: {
                var series = centralLineChartView.createSeries(ChartView.SeriesTypeLine , "Series" , xAxis , yAxis);
                series.color = Qt.rgba(Math.random() , Math.random() , Math.random() , 1);
                series.hovered.connect(function(point, state) {console.log(point);});

                for(var i = 0; i <= 17000; i ++){
                    var y = Math.random() * (-120 - (-95)) + (-95);
                    series.append(i , y);

                }
            }
        }