title: Is my code overtaxing my iPhone?
body: <p>In my application, I'm maintaining an <code>NSMutableDictionary</code> object that in normal circumstances will contain about 400-500 objects, and in some cases may contain 1500-2000.  The objects it contains are all <code>NSMutableArray</code> objects, each of which will normally contain 10-15 objects (a simple extender of <code>NSObject</code> with a few <code>NSString</code> and <code>NSDate</code> properties added) and may contain as many as 50.</p>
  
  <p>By my seat-of-the-pants calculation (assuming 100 bytes per object?) this is about 5 MB on the low side and 80 MB on the high side, so I'm not sure this is a good idea.  </p>
  
  <p>On the iPhone, how big would you want a structure like this to be before you had to implement some form of caching?</p>