title: HanekeSwift unable to allocate memory
body: <p>I'm fetching about 136 images, each one about <strong>500 KB</strong>, in order to have them cached on the disk.</p>
  
  <p>After downloading image #98, I start getting the following error for the images left (which makes me think they aren't getting cached).</p>
  
  <pre><code>2015-07-29 09:52:44.471 MyProject[299:3418965] [HANEKE][ERROR] Failed to get data for key https://s3.amazonaws.com/my_bucket/my_image_n_99.jpg
  Jul 29 09:52:45 my.host.net MyProject[299] &lt;Error&gt;: CGBitmapContextInfoCreate: unable to allocate 31492608 bytes for bitmap data
  MyProject(299,0xb039f000) malloc: *** mach_vm_map(size=31494144) failed (error code=3)
  *** error: can't allocate region
  *** set a breakpoint in malloc_error_break to debug
  </code></pre>
  
  <p>My first guess was the memory cache filled up, so I called <strong>HanekeSwift</strong>'s <code>Cache.onMemoryWarning()</code> (had to make it <code>public</code>) since it has the following implementation:</p>
  
  <pre><code>for (_, (_, memoryCache, _)) in self.formats {
      memoryCache.removeAllObjects()
  }
  </code></pre>
  
  <p>But even tho I called it (and supposedly it should clear the memory cache), I still get the error, so I don't know what's wrong.</p>
  
  <p>Any ideas?</p>