How to optimize server resource usage for Rails applications?

Question

Ruby on Rails

Good afternoon.
I have a VPS with four RAILS applications - while 10 people visit there per day. RAM - 1GB plus 512MB swap.
Three applications work fine, when I turn on the third - the memory is running out.
You can somehow defeat this without adding memory (that is, somehow twist something, but not to build the kernel from the sources).
What I use when deploying: rvm + unicorn + nginx, each application has 2 workers.
Thank you.

Answer 1

Four unicorns for 1GB? Yes, and 2 workers ?!
Here, either change the server (to a puma, for example), or remove 1 worker from all applications.