| [66] | 1 | <html><head><META http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><title>Apache Tomcat Configuration Reference - The Cluster Sender object</title><meta value="Filip Hanik" name="author"><meta value="fhanik@apache.org" name="email"></head><body vlink="#525D76" alink="#525D76" link="#525D76" text="#000000" bgcolor="#ffffff"><table cellspacing="0" width="100%" border="0"><!--PAGE HEADER--><tr><td><!--PROJECT LOGO--><a href="http://tomcat.apache.org/"><img border="0" alt=" | 
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 | 2 |     The Apache Tomcat Servlet/JSP Container | 
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 | 3 |   " align="right" src="../../images/tomcat.gif"></a></td><td><font face="arial,helvetica,sanserif"><h1>Apache Tomcat 6.0</h1></font></td><td><!--APACHE LOGO--><a href="http://www.apache.org/"><img border="0" alt="Apache Logo" align="right" src="../../images/asf-logo.gif"></a></td></tr></table><table cellspacing="4" width="100%" border="0"><!--HEADER SEPARATOR--><tr><td colspan="2"><hr size="1" noshade></td></tr><tr><!--RIGHT SIDE MAIN BODY--><td align="left" valign="top" width="80%"><table cellspacing="4" width="100%" border="0"><tr><td valign="top" align="left"><h1>Apache Tomcat Configuration Reference</h1><h2>The Cluster Sender object</h2></td><td nowrap="true" valign="top" align="right"><img border="0" hspace="0" vspace="0" height="1" width="1" src="../../images/void.gif"></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Introduction"><strong>Introduction</strong></a></font></td></tr><tr><td><blockquote> | 
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 | 4 |   <p> | 
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 | 5 |   The channel sender component is responsible for delivering outgoing cluster messages over the network. | 
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 | 6 |   In the default implementation, <code>org.apache.catalina.tribes.transport.ReplicationTransmitter</code>, | 
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 | 7 |   the sender is a fairly empty shell with not much logic around a fairly complex <code><Transport></code> | 
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 | 8 |   component the implements the actual delivery mechanism. | 
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 | 9 |   </p> | 
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 | 10 | </blockquote></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Concurrent Parallel Delivery"><strong>Concurrent Parallel Delivery</strong></a></font></td></tr><tr><td><blockquote> | 
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 | 11 |   <p> | 
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 | 12 |   In the default <code>transport</code> implementation, <code>org.apache.catalina.tribes.transport.nio.PooledParallelSender</code>, | 
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 | 13 |   Apache Tribes implements what we like to call "Concurrent Parallel Delivery".  | 
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 | 14 |   This means that we can send a message to more than one destination at the same time(parallel), and | 
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 | 15 |   deliver two messages to the same destination at the same time(concurrent). Combine these two and we have  | 
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 | 16 |   "Concurrent Parallel Delivery". | 
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 | 17 |   </p> | 
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 | 18 |   <p> | 
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 | 19 |   When is this useful? The simplest example we can think of is when part of your code is sending a 10MB message, | 
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 | 20 |   like a war file being deployed, and you need to push through a small 10KB message, say a session being replicated, | 
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 | 21 |   you don't have to wait for the 10MB message to finish, as a separate thread will push in the small message  | 
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 | 22 |   transmission at the same time. Currently there is no interrupt, pause or priority mechanism avaiable, but check back soon. | 
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 | 23 |   </p> | 
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 | 24 | </blockquote></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Nested Elements"><strong>Nested Elements</strong></a></font></td></tr><tr><td><blockquote> | 
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 | 25 |  <p> | 
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 | 26 |    The nested element <code><Transport></code> is is not required, by encouraged, as this is where | 
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 | 27 |    you would set all the socket options for the outgoing messages. Please see its attributes below. | 
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 | 28 |    There are two implementations, in a similar manner to the <a href="cluster-receiver.html">receiver</a>, one is non-blocking | 
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 | 29 |    based and the other is built using blocking IO. <br> | 
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 | 30 |    <code>org.apache.catalina.tribes.transport.bio.PooledMultiSender</code> is the blocking implemenation and  | 
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 | 31 |    <code>org.apache.catalina.tribes.transport.nio.PooledParallelSender</code>. | 
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 | 32 |    Parallel delivery is not available for the blocking implementation due to the fact that it is blocking a thread on sending data. | 
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 | 33 |  </p> | 
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 | 34 | </blockquote></td></tr></table><table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#525D76"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Attributes"><strong>Attributes</strong></a></font></td></tr><tr><td><blockquote> | 
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 | 35 |   <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Common Sender Attributes"><strong>Common Sender Attributes</strong></a></font></td></tr><tr><td><blockquote> | 
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 | 36 |     <table cellpadding="5" border="1"><tr><th bgcolor="#023264" width="15%"><font color="#ffffff">Attribute</font></th><th bgcolor="#023264" width="85%"><font color="#ffffff">Description</font></th></tr><tr><td valign="center" align="left"><strong><code>className</code></strong></td><td valign="center" align="left"> | 
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 | 37 |         Required, only available implementation is <code>org.apache.catalina.tribes.transport.ReplicationTransmitter</code> | 
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 | 38 |       </td></tr></table> | 
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 | 39 |   </blockquote></td></tr></table> | 
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 | 40 |   <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="Common Transport Attributes"><strong>Common Transport Attributes</strong></a></font></td></tr><tr><td><blockquote> | 
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 | 41 |     <table cellpadding="5" border="1"><tr><th bgcolor="#023264" width="15%"><font color="#ffffff">Attribute</font></th><th bgcolor="#023264" width="85%"><font color="#ffffff">Description</font></th></tr><tr><td valign="center" align="left"><strong><code>className</code></strong></td><td valign="center" align="left"> | 
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 | 42 |         Required, an implementation of the <code>org.apache.catalina.tribes.transport.MultiPointSender</code>.<br> | 
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 | 43 |         Non-blocking implementation is <code>org.apache.catalina.tribes.transport.nio.PooledParallelSender</code><br> | 
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 | 44 |         Blocking implementation is <code>org.apache.catalina.tribes.transport.bio.PooledMultiSender</code> | 
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 | 45 |       </td></tr><tr><td valign="center" align="left"><code>rxBufSize</code></td><td valign="center" align="left"> | 
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 | 46 |         The receive buffer size on the socket. | 
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 | 47 |         Default value is <code>25188</code> bytes. | 
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 | 48 |       </td></tr><tr><td valign="center" align="left"><code>txBufSize</code></td><td valign="center" align="left"> | 
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 | 49 |        The send buffer size on the socket. | 
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 | 50 |        Default value is <code>43800</code> bytes. | 
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 | 51 |       </td></tr><tr><td valign="center" align="left"><code>direct</code></td><td valign="center" align="left"> | 
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 | 52 |        Possible values are <code>true</code> or <code>false</code>.  | 
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 | 53 |        Set to true if you want the receiver to use direct bytebuffers when reading data | 
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 | 54 |        from the sockets. Default value is <code>false</code> | 
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 | 55 |       </td></tr><tr><td valign="center" align="left"><code>keepAliveCount</code></td><td valign="center" align="left"> | 
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 | 56 |        The number of requests that can go through the socket before the socket is closed, and reopened | 
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 | 57 |        for the next request. The default value is <code>-1</code>, which is unlimited. | 
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 | 58 |       </td></tr><tr><td valign="center" align="left"><code>keepAliveTime</code></td><td valign="center" align="left"> | 
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 | 59 |        The number of milliseconds a connection is kept open after its been opened. | 
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 | 60 |        The default value is <code>-1</code>, which is unlimited. | 
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 | 61 |       </td></tr><tr><td valign="center" align="left"><code>timeout</code></td><td valign="center" align="left"> | 
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 | 62 |         Sets the SO_TIMEOUT option on the socket. The value is in milliseconds and the default value is <code>3000</code>  | 
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 | 63 |         milliseconds. | 
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 | 64 |       </td></tr><tr><td valign="center" align="left"><code>maxRetryAttempts</code></td><td valign="center" align="left"> | 
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 | 65 |         How many times do we retry a failed message, that received a IOException at the socket level. | 
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 | 66 |         The default value is <code>1</code>, meaning we will retry a message that has failed once.  | 
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 | 67 |         In other words, we will attempt a message send no more than twice. One is the original send, and one is the  | 
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 | 68 |         <code>maxRetryAttempts</code>. | 
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 | 69 |       </td></tr><tr><td valign="center" align="left"><code>ooBInline</code></td><td valign="center" align="left"> | 
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 | 70 |         Boolean value for the socket OOBINLINE option. Possible values are <code>true</code> or <code>false</code>. | 
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 | 71 |       </td></tr><tr><td valign="center" align="left"><code>soKeepAlive</code></td><td valign="center" align="left"> | 
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 | 72 |         Boolean value for the socket SO_KEEPALIVE option. Possible values are <code>true</code> or <code>false</code>. | 
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 | 73 |       </td></tr><tr><td valign="center" align="left"><code>soLingerOn</code></td><td valign="center" align="left"> | 
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 | 74 |         Boolean value to determine whether to use the SO_LINGER socket option.  | 
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 | 75 |         Possible values are <code>true</code> or <code>false</code>. Default value is <code>true</code>. | 
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 | 76 |       </td></tr><tr><td valign="center" align="left"><code>soLingerTime</code></td><td valign="center" align="left"> | 
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 | 77 |         Sets the SO_LINGER socket option time value. The value is in seconds.  | 
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 | 78 |         The default value is <code>3</code> seconds. | 
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 | 79 |       </td></tr><tr><td valign="center" align="left"><code>soReuseAddress</code></td><td valign="center" align="left"> | 
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 | 80 |        Boolean value for the socket SO_REUSEADDR option. Possible values are <code>true</code> or <code>false</code>. | 
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 | 81 |       </td></tr><tr><td valign="center" align="left"><code>soTrafficClass</code></td><td valign="center" align="left"> | 
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 | 82 |        Sets the traffic class level for the socket, the value is between 0 and 255. | 
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 | 83 |        Default value is <code>int soTrafficClass = 0x04 | 0x08 | 0x010;</code> | 
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 | 84 |        Different values are defined in <a href="http://java.sun.com/j2se/1.5.0/docs/api/java/net/Socket.html#setTrafficClass(int)"> | 
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 | 85 |        java.net.Socket#setTrafficClass(int)</a>. | 
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 | 86 |       </td></tr><tr><td valign="center" align="left"><code>tcpNoDelay</code></td><td valign="center" align="left"> | 
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 | 87 |        Boolean value for the socket TCP_NODELAY option. Possible values are <code>true</code> or <code>false</code>. | 
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 | 88 |        The default value is <code>true</code> | 
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 | 89 |       </td></tr><tr><td valign="center" align="left"><code>throwOnFailedAck</code></td><td valign="center" align="left"> | 
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 | 90 |        Boolean value, default value is <code>true</code>. | 
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 | 91 |        If set to true, the sender will throw a <code>org.apache.catalina.tribes.RemoteProcessException</code> | 
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 | 92 |        when we receive a negative ack from the remote member. | 
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 | 93 |        Set to false, and Tribes will treat a positive ack the same way as a negative ack, that the message was received. | 
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 | 94 |       </td></tr></table> | 
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 | 95 |   </blockquote></td></tr></table> | 
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 | 96 |   <table cellpadding="2" cellspacing="0" border="0"><tr><td bgcolor="#828DA6"><font face="arial,helvetica.sanserif" color="#ffffff"><a name="PooledParallelSender Attributes"><strong>PooledParallelSender Attributes</strong></a></font></td></tr><tr><td><blockquote> | 
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 | 97 |     <table cellpadding="5" border="1"><tr><th bgcolor="#023264" width="15%"><font color="#ffffff">Attribute</font></th><th bgcolor="#023264" width="85%"><font color="#ffffff">Description</font></th></tr><tr><td valign="center" align="left"><code>poolSize</code></td><td valign="center" align="left"> | 
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 | 98 |         The maximum number of concurrent connections from A to B. | 
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 | 99 |         The value is based on a per-destination count. | 
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 | 100 |         The default value is <code>25</code> | 
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 | 101 |       </td></tr></table> | 
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 | 102 |   </blockquote></td></tr></table> | 
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 | 103 | </blockquote></td></tr></table></td></tr><!--FOOTER SEPARATOR--><tr><td colspan="2"><hr size="1" noshade></td></tr><!--PAGE FOOTER--><tr><td colspan="2"><div align="center"><font size="-1" color="#525D76"><em> | 
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 | 104 |         Copyright © 1999-2008, Apache Software Foundation | 
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 | 105 |         </em></font></div></td></tr></table></body></html> | 
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