How to choose Redis add-on on Heroku

Question

I am to new to Rails and trying to use Sidekiq with Rails 4.2 on Heroku. I thus need to choose a Redis Heroku add-on, but don't really understand how to evaluate the different services (memory-size, connections..)

I'll use Sidekiq for Mailers, Push Notifications and external API calls which end up saving one object at a time.

Any advice on which add-on to choose?

Answer 1

Disclaimer - I am with Redis Labs, provider of the Redis Cloud Heroku add-on

To get an estimate of how much memory you'll be needing and the amount of connections, do some local tests with your app. Once you have the ballpark figures, simply choose the appropriate plan from the add-on you want.

While most providers offer what appears to be the same service, Redis Cloud is the only one that actually provides an uninterrupted upgrade/downgrade procedure. That means that if you change your add-on's plan, your database remains available (with all the data, of course). AFAIK, other providers reprovision a different Redis instance when you change your plan, which requires a migration (i.e. some downtime).

Lastly, you could compare $-per-MB between the different providers - last time I checked, Redis Cloud was the cheapest and had the largest selection of plans :)