[mapserver-users] Help in plotting several tens of thousand 'pies'

[Eichner, Andreas - SID]

> We used to
> serve this data as a vector for smaller systems via GeoJSON and use
> Openlayers 2 to render on a slippery map. For a few hundred sites it was
> fine, no performance degradation or issues. When we started testing with
> larger real life samples, the browser would literally crawl. I understand
> it is because each vector feature adds to the DOM and there is a limit

Do you need to display all at once? I've read that OpenLayers can use different strategies to fetch data. Retrieving everything when the layer is created is of course the simplest one. A more sophisticated solution would be to use a BBOX filter and load data on demand. But this only makes sense if not every feature is required at the same time.