I’m also going to add more to this, I’m running a lean system (1GB ram) and a small site. It has 2 unicorn workers and between them each was taking up 30% of the memory which was causing a lot of memory thrashing, so I decided to cut down the number from 2 to 1 (which I believe can handle about 10 concurrent connections each). This made a HUGE difference and made the page loads almost instantaneous and reduced swapping by a factor of 5-10 (depending on what was being loaded).
The downside that I see now is that I can no longer use browser upgrades to update discourse. When I try to update via a browser I get
ABORTING, you do not have enough unicorn workers running
Docker Manager: FAILED TO UPGRADE
#<RuntimeError: Not enough workers>
So just something to note, not sure if this is something the team Discourse team can figure out/address - doing browser upgrades with a single unicorn worker.