title: How do you effectively compare 15000 files multiple times?
body: <p>I am comparing two almost identical folders which include hidden .svn folders which should be ignored and I want to continually quickly compare the folders as some files are patched to compared the difference without checking the unchanged matching files again.</p>
  
  <p>edit:
  Because there are so many options I'm interested in a solution that clearly exploits the knowledge from the previous compare because any other solution is not really feasable when doing repeated comparisons.</p>