content/releases/qpid-broker-j-9.2.1/book/Java-Broker-Runtime-Background-Recovery.html

<!DOCTYPE html>  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head> <meta charset="UTF-8"> <title>9.8. Background Recovery - Apache Qpid™</title> <meta http-equiv="X-UA-Compatible" content="IE=edge"/> <meta name="viewport" content="width=device-width, initial-scale=1.0"/> <link rel="stylesheet" href="/site.css" type="text/css" async="async"/> <link rel="stylesheet" href="/deferred.css" type="text/css" defer="defer"/> <script type="text/javascript">var _deferredFunctions = [];</script> <script type="text/javascript" src="/deferred.js" defer="defer"></script>   <meta name="go-import" content="qpid.apache.org git https://gitbox.apache.org/repos/asf/qpid-proton.git"/> <meta name="go-source" content="qpid.apache.org https://github.com/apache/qpid-proton/blob/go1/README.md https://github.com/apache/qpid-proton/tree/go1{/dir} https://github.com/apache/qpid-proton/blob/go1{/dir}/{file}#L{line}"/> </head> <body> <div id="-content"> <div id="-top" class="panel"> <a id="-menu-link"><img width="16" height="16" src="" alt="Menu"/></a> <a id="-search-link"><img width="22" height="16" src="" alt="Search"/></a> <ul id="-global-navigation"> <li><a id="-logotype" href="/index.html">Apache Qpid<sup>™</sup></a></li> <li><a href="/documentation.html">Documentation</a></li> <li><a href="/download.html">Download</a></li> <li><a href="/discussion.html">Discussion</a></li> </ul> </div> <div id="-menu" class="panel" style="display: none;"> <div class="flex"> <section> <h3>Project</h3> <ul> <li><a href="/overview.html">Overview</a></li> <li><a href="/components/index.html">Components</a></li> <li><a href="/releases/index.html">Releases</a></li> </ul> </section> <section> <h3>Messaging APIs</h3> <ul> <li><a href="/proton/index.html">Qpid Proton</a></li> <li><a href="/components/jms/index.html">Qpid JMS</a></li> <li><a href="/components/messaging-api/index.html">Qpid Messaging API</a></li> </ul> </section> <section> <h3>Servers and tools</h3> <ul> <li><a href="/components/broker-j/index.html">Broker-J</a></li> <li><a href="/components/cpp-broker/index.html">C++ broker</a></li> <li><a href="/components/dispatch-router/index.html">Dispatch router</a></li> </ul> </section> <section> <h3>Resources</h3> <ul> <li><a href="/dashboard.html">Dashboard</a></li> <li><a href="https://cwiki.apache.org/confluence/display/qpid/Index">Wiki</a></li> <li><a href="/resources.html">More resources</a></li> </ul> </section> </div> </div> <div id="-search" class="panel" style="display: none;"> <form action="http://www.google.com/search" method="get"> <input type="hidden" name="sitesearch" value="qpid.apache.org"/> <input type="text" name="q" maxlength="255" autofocus="autofocus" tabindex="1"/> <button type="submit">Search</button> <a href="/search.html">More ways to search</a> </form> </div> <div id="-middle" class="panel"> <ul id="-path-navigation"><li><a href="/index.html">Home</a></li><li><a href="/releases/index.html">Releases</a></li><li><a href="/releases/qpid-broker-j-9.2.1/index.html">Qpid Broker-J 9.2.1</a></li><li><a href="/releases/qpid-broker-j-9.2.1/book/index.html">Apache Qpid Broker-J</a></li><li>9.8. Background Recovery</li></ul> <div id="-middle-content"> <div class="docbook"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">9.8. Background Recovery</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="Java-Broker-Runtime-Consumers.html">Prev</a> </td><th width="60%" align="center">Chapter 9. Runtime</th><td width="20%" align="right"> <a accesskey="n" href="Java-Broker-Runtime-Message-Compression.html">Next</a></td></tr></table><hr /></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="Java-Broker-Runtime-Background-Recovery"></a>9.8. Background Recovery</h2></div></div></div><p>On startup of the Broker, or restart of a Virtualhost, the Broker restores all durable queues and their messages from disk. In the Broker's default mode the Virtualhosts do not become active until this recovery process completes. If queues have a large number of entries, this may take considerable time. During this time no messaging can be performed.</p><p>The Broker has a background recovery feature allows the system to return to operation sooner. If enabled the recovery process takes place in the background allow producers and consumers to begin work earlier.</p><p>The feature respects the message delivery order requirements of standard queues, that is any messages arriving whilst the background recovery is in flight won't overtake older messages still to be recovered from disk. There is an exception for the out of order queue types whilst background recovery is in flight. For instance, with priority queues older lower priority messages may be delivered before newer, higher priority.</p><p>To activate the feature, set a <a class="link" href="Java-Broker-Management-Managing-Entities.html#Java-Broker-Management-Managing-Entities-General" title="7.1. General Description">context variable</a> <code class="literal">use_async_message_store_recovery</code> at the desired Virtualhost, or at Broker or higher to enable the feature broker-wide.</p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3><p>The background recovery feature does not write operational log messages to indicate its progress. This means messages <a class="link" href="Java-Broker-Appendix-Operation-Logging.html#Java-Broker-Appendix-Operation-Logging-Message-MST-1004">MST-1004</a> and <a class="link" href="Java-Broker-Appendix-Operation-Logging.html#Java-Broker-Appendix-Operation-Logging-Message-MST-1005">MST-1005</a> will not be seen.</p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="Java-Broker-Runtime-Consumers.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="Java-Broker-Runtime.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="Java-Broker-Runtime-Message-Compression.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">9.7. Consumers </td><td width="20%" align="center"><a accesskey="h" href="Apache-Qpid-Broker-J-Book.html">Home</a></td><td width="40%" align="right" valign="top"> 9.9. Message Compression</td></tr></table></div></div> <hr/> <ul id="-apache-navigation"> <li><a href="http://www.apache.org/">Apache</a></li> <li><a href="http://www.apache.org/licenses/">License</a></li> <li><a href="http://www.apache.org/foundation/sponsorship.html">Sponsorship</a></li> <li><a href="http://www.apache.org/foundation/thanks.html">Thanks!</a></li> <li><a href="/security.html">Security</a></li> <li><a href="http://www.apache.org/"><img id="-apache-feather" width="48" height="14" src="" alt="Apache"/></a></li> </ul> <p id="-legal"> Apache Qpid, Messaging built on AMQP; Copyright © 2015 The Apache Software Foundation; Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>; Apache Qpid, Qpid, Qpid Proton, Proton, Apache, the Apache feather logo, and the Apache Qpid project logo are trademarks of The Apache Software Foundation; All other marks mentioned may be trademarks or registered trademarks of their respective owners </p> </div> </div> </div> </body> </html>

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