Wanted to ask some specifics about the "Message Groups" feature.
* is the feature incurring an overhead to the broker processing?
* would a large queue depth cause any issues?
* there is a note about 'grouping in memory', does this mean messsages are somehow re-ordered?
* would an ever increasing number of groups, e.g. a new group for every 2nd or 3rd message cause an issue?
Then also I wanted to ask about a specific use case:
There is a way to close a group. Is there also one to explicitly open a group?
I have a situation where a certain consumer should attract a specific group, can I tell the broker about this in advance?