title: How clean old segments from compacted log in Kafka 0.8.2
body: <p>I know that in new Kafka versions we have new retention policy option - compaction of log which delete old version of messages with same keys. But after long time we will get too many compacted log segments with old messages. How can we clean this compacted log automatically?</p>
  
  <p><strong>UDPATE</strong>: </p>
  
  <p>I should clarify that we need compact log and way to clean up old messages this in those time.
  I found discussion for same problem here <a href="http://grokbase.com/t/kafka/users/14bv6gaz0t/kafka-0-8-2-log-cleaner" rel="nofollow">http://grokbase.com/t/kafka/users/14bv6gaz0t/kafka-0-8-2-log-cleaner</a>
  but not found how we can manually issue thomstone markers for message and have not any idea this.</p>