topic Re: FeatureService draws really slow and incomplete. in ArcGIS API for Silverlight Questions

FeatureService draws really slow and incomplete.

SanajyJadhav — Sat, 20 Nov 2010 07:46:48 GMT

Hi,

I have published the FeatureService using USA_Counties data.It contains only one layer;counties.

Now the problem is when the application loads, this services gets drawn really slow. And it is not drawn completely.Only portion of it is drawn.When I zoom to any undrawn portion, then that potion is drawn but again very slowly.

I tried alter the value of property 'OnDemandCacheSize', but no use.

Am I missing something simple? Any help is appreciated.

Thanks.
Sanjay.

Re: FeatureService draws really slow and incomplete.

DominiqueBroux — Sat, 20 Nov 2010 09:22:38 GMT

You may have reached the limits of the service.
There is a limit on how many features a service can return at once (by default it's 500 for ArcGIS Server 9.3.1 and 1000 for ArcGIS Server 10).
You can change this limit, but take care that, as you mentionned, you can run into a performance issue if a huge number of graphics have to be rendered at the client level.

'OnDemandCacheSize' is used to free the graphic objects which are out of the current extent. It's not used to limit the number of objects inside the current extent.

Re: FeatureService draws really slow and incomplete.

SanajyJadhav — Mon, 22 Nov 2010 02:06:25 GMT

Thanks for information Dominique.I really appreciate it.

-
Sanjay.

Re: FeatureService draws really slow and incomplete.

dotMorten_esri — Mon, 22 Nov 2010 17:53:26 GMT

I suggest setting the layer mode to "OnDemand" and set a maximum resolution so you only see the counties when you zoom in to roughly state-level. That way all features should display and you will get reasonable rendering performance. Rendering all US counties at the same time on the client will bog down the UI thread. If you need to see the counties at country level, use a dynamic map service and set the minimum resolution of that layer to the same as the maximum resolution of the feature layer. That way the layer will automatically switch over to client side rendered features when you zoom in a bit and you will be able to "interact" with them (ie maptips etc).