Sidekiq is the magic that makes federation on mastodon work. It handles all the notifications, and pushing new toots etc. to other server.
This is what the last 6 months of activity on our server looks like
@M0YNG whoa! that's amazing!
Wow! That's an Eternal September level of traffic increase, except that it happened in October.
https://www.vice.com/en/article/nze8nb/its-september-forever