Disadvantages to rack-cache vs. Varnish in Heroku cedar stack?

Question

The previous 2 Heroku application stacks came with a Varnish layer which automatically reverse-proxy-cached content based on http headers.

The new Heroku cedar stack doe

Answer 1

There are also 3rd party options for hosted Varnish. I wrote a quick post about setting it up with Fastly/Varnish.

Fastly is a hosted Varnish solution that will sit in front of your Heroku app and serve cached responses.

Update link: https://medium.com/@harlow/scale-rails-with-varnish-http-caching-layer-6c963ad144c6

I've seen really great response times. If you can get a good cache hit-rate with Varnish you should be able to throttle back a good percentage of your dyno's.