title: Postgres: dropping huge AWS hosted table doesn't free up space
body: <p>I have a postgres (v10) database hosted on an Amazon AWS instance (which was running very low on 'Free Storage Space'). It had a 50GB table on it which I then dropped (pgAdmin - right click, delete/drop table).</p>
  
  <p>I then checked the monitoring page on our AWS console for this instance. The Free Storage Space graph did not show a 50GB jump in free space. It remained static, even after waiting a while, refreshing the page etc.</p>
  
  <p>Did dropping the 50GB table actually do anything at all?</p>