Thanks for reply!
I can’t duplicate the issue in sandcastle.
In the Sources tab, I can see multiple cesiumWorkerBootstrapper.js are generated quickly in sandcastle. But it takes few minutes to have all the cesiumWorkerBootstrapper.js ready in our application. I can see the polylines displayed when cesiumWorkerBootstrapper.js finish getting all the files it need.
I think that may related to what is discussed here https://community.cesium.com/t/slow-initial-rendering-of-polyline-polygon/9183/3
Is there a way I can load the web workers before I load geojson, so I don’t need to wait for the initial loading the web workers?
Or should I use Primitive API as an alternative way to display geometries? Is there performance difference between GeoJsonDataSource and primitives.add?
Thanks for helping!