title: Docker push to Amazon ECR slows or freezes
body: <p>Recently, my <code>docker push</code> commands to a remote ECR registry have become extremely, <em>extremely</em> slow, sometimes maybe frozen.</p>
  
  <p>It hangs long (or forever) in <code>Preparing</code>, or <code>Waiting</code>, or half-way through <code>Pushing</code>, or at 100% <code>Pushing</code>.</p>
  
  <p>I've tried this in different connections, upgrading the Docker daemon (for Mac), restarting it, casting arcane spells, and I can't get it to work as it did.</p>
  
  <p>I know this may not be the best place to ask this question, but I've exhausted all other resources. Has anyone had this issue and solved it?</p>