Too many simultaneous ClientSession.get() calls

I wrote a custom component with which I can create an arbitrary amount of entities through config files. The update of each entity includes a ClientSession.get() call to get information from a (local) server - each entity has its own instance of ClientSession via async_create_clientsession(hass).
This works fine until I define more than 20 entities: exactly 20 entities get updated but everything above that times out - the failing entities always differ. It seems like I’m hitting a threshold.
Is there a best practice to space out the updates of entities of custom components so they don’t all happen at once?

Thanks.