title: What is the smallest unit of work that is sensible to parallelize with actors?
body: <p>While Scala actors are described as light-weight, Akka actors even more so, there is obviously some overhead to using them.</p>
  
  <p>So my question is, what is the smallest unit of work that is worth parallelising with Actors (assuming it can be parallelized)? Is it only worth it if there is some potentially latency or there are a <em>lot</em> of heavy calculations?</p>
  
  <p>I'm looking for a general rule of thumb that I can easily apply in my everyday work.</p>
  
  <p>EDIT: The answers so far have made me realise that what I'm interested in is perhaps actually the <em>inverse</em> of the question that I originally asked. So:</p>
  
  <p>Assuming that structuring my program with actors is a very good fit, and therefore incurs no extra development overhead (or even incurs <em>less</em> development overhead than a non-actor implementation would), but the units of work it performs are quite small - is there a point at which using actors would be damaging in terms of performance and should be avoided?</p>