title: MongoDB limit memory
body: <p>I am using mongo for storing log files. Both mongoDB and mysql are running on the same machine, virtualizing mongo env is not an option. I am afraid I will soon run into perf issues as the logs table grows very fast. Is there a way to limit resident memory for mongo so that it won't eat all available memory and excessively slow down the mysql server?</p>
  
  <p>DB machine: Debian 'lenny' 5</p>
  
  <p>Other solutions (please comment):</p>
  
  <ul>
  <li><p>As we need all historical data, we can not use capped collections, but I am also considering using a cron script that dumps and deletes old data</p></li>
  <li><p>Should I also consider using smaller keys, as suggested on other forums?</p></li>
  </ul>