How to mix 2X & PX dynos for web process in Heroku?

Question

I want to use both 2X & PX dynos for my web application. So in my Procfile, I have the following config:

web: env WEB_CONCURRENCY=4 bundle exec unicorn -p $PORT -c ./config/unicorn.rb
web_px: env WEB_CONCURRENCY=20 bundle exec unicorn -p $PORT -c ./config/unicorn.rb

But based on Heroku metic, it seems only the web one is used to process web request (web_px one is not used most of the time).

How can I tell Heroku to use both web and web_px to process HTTP request?

Answer 1

Here is the answer from Heroku tech support:

Hi,

Our router will send requests only to dynos named web. Any other dyno is considered as a background worker and won't receive any requests. I'm afraid we don't support having two different kind of dyno sizes for the same type.