function plotbusyworkers(data) {
    $.plot($("#overallgraph"), [
        { data: data, label: "Busy workers", color: 3}
    ],
        {
            series: { stack: true, lines: { show: true, steps: false, fill: true } },
            xaxis: { mode: 'time' },
            yaxis: { min: 0, position: "left" },
        });
}