content/releases/qpid-broker-j-9.2.1/book/Java-Broker-Runtime-Connection-Limit.html (126 lines of code) (raw):

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See the License for the - specific language governing permissions and limitations - under the License. - --> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head> <meta charset="UTF-8"> <title>9.10. Connection Limits - Apache Qpid&#8482;</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> <!--[if lte IE 8]> <link rel="stylesheet" href="/ie.css" type="text/css"/> <script type="text/javascript" src="/html5shiv.js"></script> <![endif]--> <!-- Redirects for `go get` and godoc.org --> <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>&#8482;</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>9.10. Connection Limits</li></ul> <div id="-middle-content"> <div class="docbook"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">9.10. Connection Limits</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="Java-Broker-Runtime-Message-Compression.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-Memory.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-Connection-Limit"></a>9.10. Connection Limits</h2></div></div></div><p> Each connection to the Broker consumes resources while it is connected. In order to protect the Broker against malfunctioning (or malicious) client processes, it is possible to limit the number of connections that can be active on any given port. </p><p> Connection limits on AMQP ports are controlled by an attribute "maxOpenConnections" on the port. By default this takes the value of the context variable <code class="literal">qpid.port.max_open_connections</code> which in itself is defaulted to the value <code class="literal">-1</code> meaning there is no limit. </p><p> If the interpolated value of <code class="literal">maxOpenConnections</code> on an AMQP port is a positive integer, then when that many active connections have been established no new connections will be allowed (until an existing connection has been closed). Any such rejection of a connection will be accompanied by the operational log message <a class="link" href="Java-Broker-Appendix-Operation-Logging.html#Java-Broker-Appendix-Operation-Logging-Message-PRT-1005">PRT-1005</a>. </p><p> The context variable <code class="literal">qpid.port.open_connections_warn_percent</code> can be used to control when a warning log message is generated as the number of open connections approaches the limit for the port. The default value of this variable is <code class="literal">80</code> meaning that if more the number of open connections to the port has exceeded 80% of the given limit then the operatinal log message <a class="link" href="Java-Broker-Appendix-Operation-Logging.html#Java-Broker-Appendix-Operation-Logging-Message-PRT-1004">PRT-1004</a> will be generated. </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="Java-Broker-Runtime-Message-Compression.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-Memory.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">9.9. Message Compression </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"> 9.11. Memory</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 &#169; 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>