Steve,

You may want to try the 10.2 trial. I think you'll find the performance of the new XamDataChart is much better for these kinds of volumes using scatter charts.

Better yet though, with the XamDataChart, you can get even better performance if you use a line series and the CategoryDateTimeXAxis (which supports irregular spacing). The following emulates the situation you describe and returns very speedily. There are some complexities to make the various x axes align, so see my comments interspersed. These concessions aren't needed for the scatter charts, but unfortunately they aren't as zippy as this solution in the current release:

    public partial class MainPage : UserControl
    {
        List<LineSeries> series = new List<LineSeries>();
            
        public MainPage()
        {
            InitializeComponent();

            
            NumericYAxis yAxis = new NumericYAxis();
            theChart.Axes.Add(yAxis);

            List<List<LineData>> datas =
                new List<List<LineData>>();
            for (int k = 0; k < 10; k++)
            {
                series.Add(new LineSeries() 
                {
                    //we will plot Double.Nan at the end to 
                    //make the axes align, but don't actually show
                    //the value.
                    UnknownValuePlotting =
                    UnknownValuePlotting.DontPlot 
                });
                datas.Add(new List<LineData>(30000));
            }

            Random rand = new Random();
            DateTime maxX = DateTime.Now.AddYears(-100);
            List<CategoryDateTimeXAxis> axes = 
                new List<CategoryDateTimeXAxis>();

            //generating some sample data.
            for (int j = 0; j < series.Count; j++)
            {
                CategoryDateTimeXAxis xAxis = 
                    new CategoryDateTimeXAxis();
                xAxis.DateTimeMemberPath = "XValue";
                xAxis.Label = "{XVAlue:d}";
                axes.Add(xAxis);
                
                //need to use a different category xaxis 
                //because the x values are different
                //but the min/max are aligned
                //so only need to display one of them
                if (j != 0)
                {
                    xAxis.Stroke = 
                        new SolidColorBrush(Colors.Transparent);
                    xAxis.LabelSettings = new AxisLabelSettings() 
                    { 
                        Visibility = Visibility.Collapsed 
                    };
                }

                DateTime currentDate = DateTime.Now.AddYears(-100);
                double currentValue = 100;
                for (int i = 0; i < 30000; i++)
                {
                    if (currentDate > maxX)
                    {
                        maxX = currentDate;
                    }
                    datas[j].Add(new LineData() 
                    { 
                        XValue = currentDate, 
                        YValue = currentValue 
                    });
                    if (rand.NextDouble() > .5 )
                    {
                        currentValue += 5 * rand.NextDouble();
                    }
                    else
                    {
                        currentValue += -5*rand.NextDouble();
                    }
                    currentDate = 
                        currentDate.AddDays(3 + 
                        (-2 + (4 * rand.NextDouble())));
                }
                series[j].XAxis = xAxis;
                series[j].YAxis = yAxis;
                series[j].ValueMemberPath = "YValue";
            }

            for (int j = 0; j < series.Count; j++)
            {
                //force the x axes to align by plotting an non-plotted 
                //end point for each series at the max x for all series.
                if (datas[j][datas[j].Count - 1].XValue < maxX)
                {
                    datas[j].Add(new LineData() 
                    {
                        XValue = maxX, 
                        YValue = double.NaN
                    });
                }
                series[j].ItemsSource = datas[j];
                axes[j].ItemsSource = datas[j];
                theChart.Axes.Add(axes[j]);
            }

            for (int j = 0; j < series.Count; j++)
            {
                theChart.Series.Add(series[j]);
            }
        }
    }

    public class LineData
    {
        public DateTime XValue { get; set; }
        public double YValue { get; set; }
    }

Let me know if you have any questions. Hope this helps!

-Graham

Hello,

I'm trying to find a silverlight chart that is capable of holding up to 10 time series, each about 30,000 points.  I'm plotting them as a scatter plot because the times are irregularly spaced.  I just downloaded the trial 2010.1 version and while the chart looks great, it's taking a while to load with just one series of 30,000 points - about 60 secs.  I've tried:

1. Create a list of key value pairs and bind that to the series as the data source

2. add the points in a loop one by one as datapoints

3. adjusting the unit of the x axis manually

4. adjusting the label visibility of the x axis manually.

None of these had an impact on the load time.

Is there something I'm missing, or is this the expected performance.

Thanks for any help.

-Steve

We were using 9.1 and after shifting to 10.1 we have clear perfomrnace gains, and chart load time has change to 3 to 4 seconds from appox 15 seconds.
Is there still any progress in this context?

Thanks

Hi Graham,

We are also facing same issue, can you tell me in which release this solution will be available.

We are doing data point adding as following: where series are of Line Type and has been definded in xaml

this.cht.RefreshEnabled = false;
Series s1 = this.chtValuationMuliple.Series[0];
Series s2 = this.chtValuationMuliple.Series[1];

DataPoint dp;
for (int i = 0; i < MyCount; i++)
{
 dp = new DataPoint(val1, date);               
        s1.DataPoints.Add(dp);

 dp = new DataPoint(val2);
        s2.DataPoints.Add(dp);
}

this.cht.RefreshEnabled = true;

My application stucks for about 15 seconds on this.cht.RefreshEnabled = true;

Can you please suggest me some work around?

Thanks