| [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><!--LEFT SIDE NAVIGATION--><td nowrap="true" valign="top" width="20%"><p><strong>Links</strong></p><ul><li><a href="../index.html">Docs Home</a></li><li><a href="index.html">Config Ref. Home</a></li></ul><p><strong>Top Level Elements</strong></p><ul><li><a href="server.html">Server</a></li><li><a href="service.html">Service</a></li></ul><p><strong>Executors</strong></p><ul><li><a href="executor.html">Executor</a></li></ul><p><strong>Connectors</strong></p><ul><li><a href="http.html">HTTP</a></li><li><a href="ajp.html">AJP</a></li></ul><p><strong>Containers</strong></p><ul><li><a href="context.html">Context</a></li><li><a href="engine.html">Engine</a></li><li><a href="host.html">Host</a></li><li><a href="cluster.html">Cluster</a></li></ul><p><strong>Nested Components</strong></p><ul><li><a href="globalresources.html">Global Resources</a></li><li><a href="loader.html">Loader</a></li><li><a href="manager.html">Manager</a></li><li><a href="realm.html">Realm</a></li><li><a href="resources.html">Resources</a></li><li><a href="valve.html">Valve</a></li></ul><p><strong>Cluster Elements</strong></p><ul><li><a href="cluster.html">Cluster</a></li><li><a href="cluster-manager.html">Manager</a></li><li><a href="cluster-channel.html">Channel</a></li><li><a href="cluster-membership.html">Channel/Membership</a></li><li><a href="cluster-sender.html">Channel/Sender</a></li><li><a href="cluster-receiver.html">Channel/Receiver</a></li><li><a href="cluster-interceptor.html">Channel/Interceptor</a></li><li><a href="cluster-valve.html">Valve</a></li><li><a href="cluster-deployer.html">Deployer</a></li><li><a href="cluster-listener.html">ClusterListener</a></li></ul><p><strong>Global Settings</strong></p><ul><li><a href="systemprops.html">System properties</a></li></ul></td><!--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"><small><a href="printer/cluster-sender.html"><img alt="Printer Friendly Version" border="0" src="../images/printer.gif"><br>print-friendly<br>version |
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| 4 | </a></small></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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| 5 | <p> |
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| 6 | The channel sender component is responsible for delivering outgoing cluster messages over the network. |
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| 7 | In the default implementation, <code>org.apache.catalina.tribes.transport.ReplicationTransmitter</code>, |
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| 8 | the sender is a fairly empty shell with not much logic around a fairly complex <code><Transport></code> |
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| 9 | component the implements the actual delivery mechanism. |
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| 10 | </p> |
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| 11 | </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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| 12 | <p> |
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| 13 | In the default <code>transport</code> implementation, <code>org.apache.catalina.tribes.transport.nio.PooledParallelSender</code>, |
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| 14 | Apache Tribes implements what we like to call "Concurrent Parallel Delivery". |
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| 15 | This means that we can send a message to more than one destination at the same time(parallel), and |
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| 16 | deliver two messages to the same destination at the same time(concurrent). Combine these two and we have |
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| 17 | "Concurrent Parallel Delivery". |
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| 18 | </p> |
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| 19 | <p> |
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| 20 | 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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| 21 | 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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| 22 | 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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| 23 | transmission at the same time. Currently there is no interrupt, pause or priority mechanism avaiable, but check back soon. |
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| 24 | </p> |
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| 25 | </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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| 26 | <p> |
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| 27 | The nested element <code><Transport></code> is is not required, by encouraged, as this is where |
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| 28 | you would set all the socket options for the outgoing messages. Please see its attributes below. |
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| 29 | 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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| 30 | based and the other is built using blocking IO. <br> |
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| 31 | <code>org.apache.catalina.tribes.transport.bio.PooledMultiSender</code> is the blocking implemenation and |
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| 32 | <code>org.apache.catalina.tribes.transport.nio.PooledParallelSender</code>. |
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| 33 | 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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| 34 | </p> |
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| 35 | </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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| 36 | <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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| 37 | <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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| 38 | Required, only available implementation is <code>org.apache.catalina.tribes.transport.ReplicationTransmitter</code> |
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| 39 | </td></tr></table> |
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| 40 | </blockquote></td></tr></table> |
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| 41 | <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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| 42 | <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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| 43 | Required, an implementation of the <code>org.apache.catalina.tribes.transport.MultiPointSender</code>.<br> |
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| 44 | Non-blocking implementation is <code>org.apache.catalina.tribes.transport.nio.PooledParallelSender</code><br> |
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| 45 | Blocking implementation is <code>org.apache.catalina.tribes.transport.bio.PooledMultiSender</code> |
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| 46 | </td></tr><tr><td valign="center" align="left"><code>rxBufSize</code></td><td valign="center" align="left"> |
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| 47 | The receive buffer size on the socket. |
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| 48 | Default value is <code>25188</code> bytes. |
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| 49 | </td></tr><tr><td valign="center" align="left"><code>txBufSize</code></td><td valign="center" align="left"> |
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| 50 | The send buffer size on the socket. |
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| 51 | Default value is <code>43800</code> bytes. |
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| 52 | </td></tr><tr><td valign="center" align="left"><code>direct</code></td><td valign="center" align="left"> |
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| 53 | Possible values are <code>true</code> or <code>false</code>. |
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| 54 | Set to true if you want the receiver to use direct bytebuffers when reading data |
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| 55 | from the sockets. Default value is <code>false</code> |
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| 56 | </td></tr><tr><td valign="center" align="left"><code>keepAliveCount</code></td><td valign="center" align="left"> |
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| 57 | The number of requests that can go through the socket before the socket is closed, and reopened |
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| 58 | for the next request. The default value is <code>-1</code>, which is unlimited. |
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| 59 | </td></tr><tr><td valign="center" align="left"><code>keepAliveTime</code></td><td valign="center" align="left"> |
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| 60 | The number of milliseconds a connection is kept open after its been opened. |
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| 61 | The default value is <code>-1</code>, which is unlimited. |
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| 62 | </td></tr><tr><td valign="center" align="left"><code>timeout</code></td><td valign="center" align="left"> |
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| 63 | 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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| 64 | milliseconds. |
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| 65 | </td></tr><tr><td valign="center" align="left"><code>maxRetryAttempts</code></td><td valign="center" align="left"> |
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| 66 | How many times do we retry a failed message, that received a IOException at the socket level. |
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| 67 | The default value is <code>1</code>, meaning we will retry a message that has failed once. |
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| 68 | 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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| 69 | <code>maxRetryAttempts</code>. |
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| 70 | </td></tr><tr><td valign="center" align="left"><code>ooBInline</code></td><td valign="center" align="left"> |
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| 71 | Boolean value for the socket OOBINLINE option. Possible values are <code>true</code> or <code>false</code>. |
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| 72 | </td></tr><tr><td valign="center" align="left"><code>soKeepAlive</code></td><td valign="center" align="left"> |
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| 73 | Boolean value for the socket SO_KEEPALIVE option. Possible values are <code>true</code> or <code>false</code>. |
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| 74 | </td></tr><tr><td valign="center" align="left"><code>soLingerOn</code></td><td valign="center" align="left"> |
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| 75 | Boolean value to determine whether to use the SO_LINGER socket option. |
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| 76 | Possible values are <code>true</code> or <code>false</code>. Default value is <code>true</code>. |
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| 77 | </td></tr><tr><td valign="center" align="left"><code>soLingerTime</code></td><td valign="center" align="left"> |
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| 78 | Sets the SO_LINGER socket option time value. The value is in seconds. |
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| 79 | The default value is <code>3</code> seconds. |
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| 80 | </td></tr><tr><td valign="center" align="left"><code>soReuseAddress</code></td><td valign="center" align="left"> |
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| 81 | Boolean value for the socket SO_REUSEADDR option. Possible values are <code>true</code> or <code>false</code>. |
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| 82 | </td></tr><tr><td valign="center" align="left"><code>soTrafficClass</code></td><td valign="center" align="left"> |
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| 83 | Sets the traffic class level for the socket, the value is between 0 and 255. |
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| 84 | Default value is <code>int soTrafficClass = 0x04 | 0x08 | 0x010;</code> |
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| 85 | 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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| 86 | java.net.Socket#setTrafficClass(int)</a>. |
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| 87 | </td></tr><tr><td valign="center" align="left"><code>tcpNoDelay</code></td><td valign="center" align="left"> |
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| 88 | Boolean value for the socket TCP_NODELAY option. Possible values are <code>true</code> or <code>false</code>. |
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| 89 | The default value is <code>true</code> |
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| 90 | </td></tr><tr><td valign="center" align="left"><code>throwOnFailedAck</code></td><td valign="center" align="left"> |
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| 91 | Boolean value, default value is <code>true</code>. |
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| 92 | If set to true, the sender will throw a <code>org.apache.catalina.tribes.RemoteProcessException</code> |
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| 93 | when we receive a negative ack from the remote member. |
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| 94 | 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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| 95 | </td></tr></table> |
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| 96 | </blockquote></td></tr></table> |
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| 97 | <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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| 98 | <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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| 99 | The maximum number of concurrent connections from A to B. |
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| 100 | The value is based on a per-destination count. |
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| 101 | The default value is <code>25</code> |
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| 102 | </td></tr></table> |
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| 103 | </blockquote></td></tr></table> |
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| 104 | </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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| 105 | Copyright © 1999-2008, Apache Software Foundation |
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| 106 | </em></font></div></td></tr></table></body></html> |
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