<div class="wiki-content maincontent"><h2>Kaha Persistence</h2>

<p>Kaha Peristence is a storage solution written especially for message persistence and is part of the ActiveMQ project. It's tuned to provide optimal performance for typical message usage patterns, which involves writing/reading and discarding messages that are persisted very quickly.</p>

<p>Data stored in Kaha is appended to data logs - the log files are discarded once there is no longer interest in the data contained in the log.</p>

<h3>Configuring Kaha Persistence</h3>

<p>In the broker XML specify the persistence adaptor to be Kaha e.g.</p>

<p>ActiveMQ 5.0 and above:</p>

<structured-macro ac:macro-id="f1210018-4a80-4011-a088-a6da3b1db3bc" ac:name="code" ac:schema-version="1"><plain-text-body>
 &lt;broker brokerName="broker" persistent="true" useShutdownHook="false"&gt;
    &lt;transportConnectors&gt;
      &lt;transportConnector uri="tcp://localhost:61616"/&gt;
    &lt;/transportConnectors&gt;
    &lt;persistenceAdapter&gt;
      &lt;kahaPersistenceAdapter directory="activemq-data" maxDataFileLength="33554432"/&gt;
    &lt;/persistenceAdapter&gt;
  &lt;/broker&gt;
</plain-text-body></structured-macro>


<p>ActiveMQ 4.1 and earlier:</p>

<structured-macro ac:macro-id="a53390c5-5c6b-4155-b84d-be230563faf1" ac:name="code" ac:schema-version="1"><plain-text-body>
 &lt;broker brokerName="broker" persistent="true" useShutdownHook="false"&gt;
    &lt;transportConnectors&gt;
      &lt;transportConnector uri="tcp://localhost:61616"/&gt;
    &lt;/transportConnectors&gt;
    &lt;persistenceAdapter&gt;
      &lt;kahaPersistenceAdapter dir="activemq-data" maxDataFileLength="33554432"/&gt;
    &lt;/persistenceAdapter&gt;
  &lt;/broker&gt;
</plain-text-body></structured-macro></div>