title: How many workers in a Node.js relatively to CPU cores
body: <p>When working with <code>child_process</code> or <code>cluster</code>, is it best to have as many subprocess as CPU cores, or should we subtract one to that number, as the master process is already sitting on one of them ?</p>
  <p>Expanding on this question, how are things handled by Node.js when we spawn <em>more</em> processes than there are CPU cores on the machine ?</p>