Just left a session where they discussed 10.6.1 and newer 4.x JSAPI enabling much faster FeatureLayers by downloading lighter payloads and using quantization. Does this apply to runtime?
Yes, this is something we have plans to do. We already support quantization in the Interaction_No_Cache mode of ServiceFeatureTable, and the Interaction_Cache mode temporarily caches features and doesn't query for the same ones again in order to reduce data exchange and improve performance.
We'll be looking at leveraging other options such as protocol buffers, feature tiles, etc in a future release to improve things even more.
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