Dario Crivelli
We don't pose limits, but consider that each subscription causes some memory to be allocated on the Server;
so, if this usage were associated to a huge number of clients, you should have to perform a load test in order to validate your environment.
Note that a large number of items in a single table may also cause the subscription requests to become very long.
So, you should test the system to ensure that the <request_limit> configuration will not prevent any subscription request;
alternatively, you may consider using "group ids" for table specifications on the client side, which is allowed by all client libraries (please specify which client library you are using, if you need details).