Highchart line chart tooltip issues with large dataset

Question

I have quite a large dataset displaying in a highcharts line chart. Tooltips are enabled but the displaying of the tooltip is quite erratic, especially when zoomed in.

You can see the dataset here: http://jsfiddle.net/ARfcB/2/

$(function () {

$('#container').highcharts({

    chart: {
            type: 'line',
            zoomType: "x"
        },
        plotOptions: {
            line: {
                marker: {
                    enabled: true
                },
                animation: true
            }
        },
        legend: {
            enabled: true,
            layout: "vertical",
            align: 'right',
            verticalAlign: 'middle'
        },
        tooltip: {
            enabled: true,
            shared: false
        },
        xAxis: {
            type: "datetime"
        },
        yAxis: {
            title: {
                text: 'Up/Down'
            },
            labels: {
                style: {
                    color: "blue"
                }
            },
            min: 0,
            max: 1,
            tickInterval: 1,
            categories: ['Down', 'Up']
        },
        credits: {
            enabled: false
        },
        series: "large dataset on jsfiddle page"

}); });

The graph basically shows an up/down value for each series. When the mouse is hovering over the 'down' values, no tooltip displays. When zooming in its even worse. Tooltips are displayed but for a point other than the one that is hovered over; and never for the 'down' values.

I'm wondering is this just because the dataset is quite large or is it an issue with highcharts itself.

Thanks in advance for the help.

Answer 1

Your data should be sorted via x ascending.