Hi Gino,

Keeping track of the subscribed item on the adapter and sending to the Lightstreamer Server just the itemEvents for Items actually subscribed, is a best practice compared to sending all the ItemEvents to the Lightstreamer Server regardless they were subscribed or not and letting the Server deal with them.
Actually the Lightstreamer SDK for Node Adapters should throw an exception when your adapter tries to send an ItemEvent for an Item not subscribed. Avoid to create unnecessary exceptions is also a good practice, so, yes, I would keep track of the subscribed items, especially if there are thousand of Items and just a small part of them are actually subscribed.
By the way, do you see these exceptions?