title: MongoDB Capped Collection Maximum allowable size
body: <p>I'm using a mongodb capped collection which is tailable. I want to set the size of it to a maximum value as I don't want to really have the oldest records removed according to the FIFO rule. </p>
  
  <p>I want the data to pesist for as long as possible whilst keeping the features of a capped collection.</p>
  
  <p>Thanks</p>