title: What does "nodetool compact" do for DateTieredCompactionStrategy?
body: <p><a href="https://docs.datastax.com/en/cassandra/2.1/cassandra/tools/toolsCompact.html" rel="noreferrer">The documentation for nodetool compact says</a>:</p>
  
  <blockquote>
    <p>This command starts the compaction process on tables that use the
    SizeTieredCompactionStrategy and DateTieredCompactionStrategy. You can
    specify a keyspace for compaction.</p>
  </blockquote>
  
  <p>But what it does for DateTieredCompactionStrategy?</p>
  
  <p>Side question: what is <code>-s, --split-output</code> parameter? It is explained as: <code>Use -s to not create a single big file</code>. I'm confused - isn't that the purpose of <code>nodetool compact</code>?</p>