title: Major performance difference between two Oracle database instances
body: <p>I am working with two instances of an Oracle database, call them <code>one</code> and <code>two</code>. <code>two</code> is running on better hardware (hard disk, memory, CPU) than <code>one</code>, and <code>two</code> is one minor version behind <code>one</code> in terms of Oracle version (both are 11g). Both have the exact same table <code>table_name</code> with exactly the same indexes defined. I load 500,000 identical rows into <code>table_name</code> on both instances. I then run, on both instances:</p>
  
  <pre><code>delete from table_name;
  </code></pre>
  
  <p>This command takes 30 seconds to complete on <code>one</code> and 40 minutes to complete on <code>two</code>. Doing INSERTs and UPDATEs on the two tables has similar performance differences. Does anyone have any suggestions on what could have such a drastic impact on performance between the two databases?</p>