<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>