For a project we aim to use Exhcange Web Services Streaming Notifications to monitor the calendars for a number of resources. We need to do some processing whenever a resource is booked or when such a booking is modified.
I know there are certain throttling variables etc. that might have an impact on how the application is designed. Assuming I follow best practice, how can these notification subscriptions be expected to affect the load on the Exchange server? I can't manage to find any useful numbers or even hints on this subject.
We expect to monitor the calendars of up to about 100 mailboxes.
In simpler terms - are notifications (in particular streaming) "cheap" so that we don't need to worry much about server load from this? Or are they "expensive", so that we should expect this number of subscriptions to have a not insignificant effect on server load?
I realize the server load will also be impacted by any calls we make to Exchange in response to notifications. This question is mainly about the performance impact of the notification subscription themselves. Typically, I expect that in response to an updated item, we will load that item (including the item's list of participants).
IMO, Streaming notifications are pretty efficient. In past years, my app has been doing Push Notifications in shops with several hundred to several thousand MBs being subscribed, and while we have been throttled, I think using impersonation helps to avoid that. Streaming Notifications are overall at least as efficient as Push, and much more firewall friendly. For a real-world Exchange setup, i.e. multiple CAS and MBX servers, I don't see how 100 MB would put any real load on it.