title: How to improve asp.net AJAX autocomplete performance
body: <p>My web site has city,state and zip code autocomplete feature. </p>
  
  <p>If user types in 3 characters of a city in the textbox, then top 20 cities starting with those characters are shown.
  As of now, Autocomplete method in our application queries sql 2005 database which has got around 900,000 records related to city,state and zip.</p>
  
  <p>But the response time to show the cities list seems to be very very slow.</p>
  
  <p>Hence, for peformance optimization, is it a good idea to store the location data into Lucene index or may be in Active directory and then pull the data from there?</p>
  
  <p>Which one will be faster...Lucene or Activedirectory?And what are the pros and cons of each?Any suggestions please?</p>
  
  <p>Thanks a bunch!</p>