What are your settings at? It is supposed to be a limit PER event type and attribute, so those old records should not be causing less of the other types to save less information.
You could also try setting both of those to 10, and wait overnight for the cleanup which should kill a lot of that old stuff. There is also an endpoint command to force a cleanup cycle. Going to see if I can find those links.
UPDATE:
Here is info about the number of days old events are kept. You could set this low enough to purge those, run a cleanup and then set it back if you want.
The database cleanup link is
your.hub.ip/hub/cleanupDatabase
