title: ActiveDirectory performance with query on large database
body: <p>How hard is it for an AD server to deliver the search result of the following LDAP query?</p>
  
  <pre><code>(&amp;(objectclass=user)(objectcategory=person)(msRTCSIP-UserEnabled=TRUE))
  </code></pre>
  
  <p>Lets say for 100k hits? 250k?</p>
  
  <p>The alternative is to do a running query for each update, which is anywhere from a few per second to 500+ per second, using a query with lots of wildcards. I assume that wildcard searches are quite resource demanding for the database to look up.</p>
  
  <p>The idea is that if it is comparatively easy for the server to make the above search initially, when we start the system, we can cut the other query to something far less frequent.</p>