Rails app, MongoDB, and EngineYard

Question

If I want to setup a test environment on EngineYard for my Rails app with MySQL, MongoDB, and the Jenkins Continuous Integration server included, do I set all this up as a Single Instance Environment or as a multiple-instance environment? Would I need to setup a separate utility instance just for MongoDB or would they be able to live on the same "Single Instance Environment"?

Answer 1

Running this on a solo instance is fine for testing, however you may run into performance issues. MongoDB mmaps data files and MySQL allocates RAM for InnoDB buffers, so depending on the size of your dataset[s] you could easily exhaust the available RAM on a solo instance.

Engine Yard provides a public repo with some recipes that may help you set this up (particularly MongoDB). They're available here: https://github.com/engineyard/ey-cloud-recipes

Disclaimer: I work for Engine Yard, but this isn't official support. Please open a ticket if you'd like some of that!

Answer 2

You can set them up in a solo (i.e. single instance) environment. As long as they aren't set up to sit on conflicting ports or use conflicting directories, you should be fine. I have a solo environment with mysql, redis, and cassandra running without issue.