I believe routing is not random, but round robin. I'd like Heroku to confirm. It's still a problem. If you are looking to run Unicorn on Heroku, use the heroku-

I believe routing is not random, but round robin. I'd like Heroku to confirm. It's still a problem. If you are looking to run Unicorn on Heroku, use the heroku-forward gem (https://github.com/dblock/heroku-forward https://github.com/dblock/heroku-forward). Works well, but application RAM is quickly its own issue, we failed to run that in production as our app takes ~300MB.