title: Unicorn: Which number of worker processes to use?
body: <p>I am running a Ruby on Rails app on a virtual Linux server that is capped at 1GB RAM. Currently, I am constantly hitting the limit and would like to optimize memory utilization. One option I am looking at is reducing the number of unicorn workers.</p>
  
  <p><strong>So what is the best way to determine the number of unicorn workers to use?</strong></p>
  
  <p>The current setting is 10 workers, but the maximum number of requests per second I have seen on Google Analytics Real-Time is 3 (only scored once at a peak time; in 99% of the time not going above 1 request per second).</p>
  
  <p>So is it a save assumption that I can - for now - go with 4 workers, leaving room for unexpected amounts of requests? <strong>What are the metrics I should have a look at for determining the number of workers and what are the tools I can use for that on my Ubuntu machine?</strong></p>