title: MongoDB is using too much memory
body: <p>I'm working with MongoDB on a 32bits CentOS VPS with 1GB of internal memory.
  It works fine most of the time, but every now and then it's memory usage spikes and crashes my server.</p>
  
  <p>Is there a way to prevent this, for example, by limiting the memory and CPU that MongoDB daemon uses?</p>
  
  <p>I was thinking of running the Mongo daemon with <code>ionice</code> and giving it a low priority, but I'm not sure if that would work.</p>
  
  <p>Any help or pointers are welcome!</p>