Layer Load Performance

Question

Is there a way to handle performance of the map when large number of layers are loaded.

currently we have scenarios where over 200 layers are being loaded depending on the need, and it slows everything down.

Layers sets are combination of MapImageLayer and FeatureLayer.

Edit 1 - MapImageLayers are registered by individuals themselves. They have MapServers running they want to add. Some of these MapServers are large to say the least.

Aeseir · Answer

Edited the post to explain the situation further. Layers are added ad-hoc by users, and they are oftern series of MapServers with number of sublayers.

Unfortunately since a lot of data is outside of our control, our filtering capability is limited to only content we manage.

Aeseir · Answer

Edited the post to explain the situation further. Layers are added ad-hoc by users, and they are oftern series of MapServers with number of sublayers.

Some of your ideas we have already implemented (1,2), 4 is handled via extent of the mapview, however if you can advise how to ensure this is enforced I can review. Item 3 can't confirm as these are external brought in by users.

RRubalcava · Answer

I would echo @JeffreyWilkerson comments. Spot on. With the scale dependency set in the map view, the layers won't load data, but they will send requests for details if referenced as item ids, things like title, name, basically stuff needed for layer list or other resources. I have worked with customers that have had to work with large numbers of layers in their applications and there are some methods that have helped.

* Group layers by theme* Not all users need all layers at once, they are usually looking for certain pieces of information. You can add a button or dropdown that allows them to turn on all layers, say related to "Utility Assets" or something like that. Then you programatically add the desired layers to the map.

* A custom layer list/data add tool.* Provide a way to let users choose the layers they want to see via your own tool so you can control when they are loaded. Dropdown or picklist type component.

In both these cases, you probably have a base set of layers like parcels or boundaries always on, but you can now better control when and what layers are loaded to help alleviate the load.