| <div class="docbook"><div class="navheader"><table summary="Navigation header" width="100%"><tr><th align="center" colspan="3">Chapter 9. Runtime</th></tr><tr><td align="left" width="20%"><a accesskey="p" href="Java-Broker-Security-Configuration-Encryption.html">Prev</a> </td><th align="center" width="60%"> </th><td align="right" width="20%"> <a accesskey="n" href="Java-Broker-Runtime-Disk-Space-Management.html">Next</a></td></tr></table><hr /></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a id="Java-Broker-Runtime"></a>Chapter 9. Runtime</h1></div></div></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="section"><a href="Java-Broker-Runtime.html#Java-Broker-Runtime-Logging">9.1. Logging</a></span></dt><dd><dl><dt><span class="section"><a href="Java-Broker-Runtime.html#Java-Broker-Runtime-Logging-Concepts">9.1.1. Concepts</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime.html#Java-Broker-Runtime-Logging-Default-Configuration">9.1.2. Default Configuration</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime.html#Java-Broker-Runtime-Logging-Loggers">9.1.3. Loggers</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime.html#Java-Broker-Runtime-Logging-InclusionRules">9.1.4. Inclusion Rules</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime.html#Java-Broker-Runtime-Logging-Management">9.1.5. Logging Management</a></span></dt></dl></dd><dt><span class="section"><a href="Java-Broker-Runtime-Disk-Space-Management.html">9.2. Disk Space Management</a></span></dt><dd><dl><dt><span class="section"><a href="Java-Broker-Runtime-Disk-Space-Management.html#Java-Broker-Runtime-Disk-Space-Management-Producer-Flow-Control">9.2.1. Disk quota-based flow control</a></span></dt></dl></dd><dt><span class="section"><a href="Java-Broker-Runtime-Transaction-Timeout.html">9.3. Transaction Timeout</a></span></dt><dd><dl><dt><span class="section"><a href="Java-Broker-Runtime-Transaction-Timeout.html#Java-Broker-Runtime-Transaction-Timeout-GeneralInformation">9.3.1. General Information</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Transaction-Timeout.html#Java-Broker-Runtime-Transaction-Timeout-Purpose">9.3.2. Purpose</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Transaction-Timeout.html#Java-Broker-Runtime-Transaction-Timeout-Effect">9.3.3. Effect</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Transaction-Timeout.html#Java-Broker-Runtime-Transaction-Timeout-Configuration">9.3.4. Configuration</a></span></dt></dl></dd><dt><span class="section"><a href="Java-Broker-Runtime-Handling-Undeliverable-Messages.html">9.4. Handing Undeliverable Messages</a></span></dt><dd><dl><dt><span class="section"><a href="Java-Broker-Runtime-Handling-Undeliverable-Messages.html#Java-Broker-Runtime-Handling-Undeliverable-Messages-Introduction">9.4.1. Introduction</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Handling-Undeliverable-Messages.html#Java-Broker-Runtime-Handling-Undeliverable-Messages-Maximum-Delivery-Count">9.4.2. Maximum Delivery Count</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Handling-Undeliverable-Messages.html#Java-Broker-Runtime-Handling-Undeliverable-Messages-Dead-Letter-Queues">9.4.3. Alternate Binding</a></span></dt></dl></dd><dt><span class="section"><a href="Java-Broker-Runtime-Close-Connection-When-No-Route.html">9.5. Closing client connections on unroutable mandatory messages</a></span></dt><dd><dl><dt><span class="section"><a href="Java-Broker-Runtime-Close-Connection-When-No-Route.html#Java-Broker-Runtime-Close-Connection-When-No-Route-Summary">9.5.1. Summary</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Close-Connection-When-No-Route.html#Java-Broker-Runtime-Close-Connection-When-No-Route-Configuration">9.5.2. Configuring | |
| <span class="emphasis"><em>closeWhenNoRoute</em></span> | |
| </a></span></dt></dl></dd><dt><span class="section"><a href="Java-Broker-Runtime-Flow-To-Disk.html">9.6. Flow to Disk</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Consumers.html">9.7. Consumers</a></span></dt><dd><dl><dt><span class="section"><a href="Java-Broker-Runtime-Consumers.html#Java-Broker-Runtime-Consumers-Prioirty">9.7.1. Priority</a></span></dt></dl></dd><dt><span class="section"><a href="Java-Broker-Runtime-Background-Recovery.html">9.8. Background Recovery</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Message-Compression.html">9.9. Message Compression</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Connection-Limit.html">9.10. Connection Limits</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Memory.html">9.11. Memory</a></span></dt><dd><dl><dt><span class="section"><a href="Java-Broker-Runtime-Memory.html#Java-Broker-Runtime-Memory-Introduction">9.11.1. Introduction</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Memory.html#Java-Broker-Runtime-Memory-Types">9.11.2. Types of Memory</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Memory.html#Java-Broker-Runtime-Memory-Usage">9.11.3. Memory Usage in the Broker</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Memory.html#Java-Broker-Runtime-Memory-Low-Memory">9.11.4. Low Memory Conditions</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Memory.html#Java-Broker-Runtime-Memory-Defaults">9.11.5. Defaults</a></span></dt><dt><span class="section"><a href="Java-Broker-Runtime-Memory.html#Java-Broker-Runtime-Memory-Tuning">9.11.6. Memory Tuning the Broker</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="Java-Broker-Runtime-Logging"></a>9.1. Logging</h2></div></div></div><p>This section describes the flexible logging capabilities of the Apache Qpid Broker-J.</p><p> | |
| </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The Broker is capable of sending logging events to a variety of destinations including | |
| plain files, remote syslog daemons, and an in-memory buffer (viewable from Management). | |
| The system is also open for extension meaning it is possible to produce a plugin to log to | |
| a bespoke destination.</p></li><li class="listitem"><p>Logging can be dynamically configured at runtime. For instance, it is possible to | |
| temporarily increase the logging verbosity of the system whilst a problem is investigated | |
| and then revert later, all without the need to restart the Broker.</p></li><li class="listitem"><p>Virtualhosts can be configured to generate their own separate log, and the Broker is | |
| capable of generating a log either inclusive or exclusive of virtualhost events.</p></li><li class="listitem"><p>Logs are accessible over Management, removing the need for those operating the Broker | |
| to have shell level access.</p></li></ul></div><p> | |
| </p><p>In the remainder of this section you will first find a description of the concepts used in | |
| the logging subsystem. Next, you find a description of the default configuration. The section | |
| then concludes with a in-depth description of the loggers themselves and how they may be | |
| configured.</p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Runtime-Logging-Concepts"></a>9.1.1. Concepts</h3></div></div></div><p>The logging subsystem uses two concepts:</p><p> | |
| </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>A <span class="emphasis"><em>Logger</em></span> is responsible for production of a log. The Broker | |
| ships a variety of loggers, for instance, a file logger, which is capable of writing a | |
| log file to the file system, a Syslog Logger capable of writing to a remote syslog | |
| daemon and console logger capable of writing to stdout or stderr.</p><p>Loggers are attached at two points within the Broker Model; the Broker itself and | |
| the virtualhosts. Loggers attached at the Broker can capture log events for the system | |
| as a whole, or can exclude events related to virtualhosts.</p><p>Loggers attached to a virtualhost capture log events relating to that virtualhost | |
| only.</p><p>The Broker and virtualhosts can have zero or more Loggers. If no loggers are | |
| configured, no logging is generated at all.</p></li><li class="listitem"><p><span class="emphasis"><em>Inclusion rules</em></span> govern what appears within a log. Inclusion | |
| rules are associated with Loggers. This means it is possible for different Loggers to | |
| have different contents.</p><p>A Logger with no inclusion rules will produce an empty log.</p></li></ul></div><p> | |
| </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Runtime-Logging-Default-Configuration"></a>9.1.2. Default Configuration</h3></div></div></div><p>The default configuration is designed to be suitable for use without change in small | |
| production environments. It has the following characteristics:</p><p> | |
| </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The Broker generates a single log file <code class="literal">qpid.log</code>. This logfile is | |
| rolled automatically when the file reaches 100MB. A maximum history of one file is | |
| retained. On restart the the log will be appended to.</p><p>The log contains: </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; "><li class="listitem"><p>All operational logging events. See <a class="xref" href="Java-Broker-Appendix-Operation-Logging.html" title="Appendix C. Operational Logging">Appendix C, <em>Operational Logging</em></a>.</p></li><li class="listitem"><p>Log events from Qpid itself deemed informational or | |
| higher.</p></li><li class="listitem"><p>Log events from Qpid's dependencies (such as Derby or Jetty) that are | |
| deemed warning or higher.</p></li></ul></div><p> | |
| </p><p>The default location for the log file is | |
| <code class="literal">${QPID_WORK}/log/qpid.log</code>.</p></li><li class="listitem"><p>The Broker also caches the last 4096 log events in a memory cache. By default, the | |
| memory logger logs the same things the file logger does.</p></li></ul></div><p> | |
| </p><p>The configuration can be customised at runtime using Management. This makes it possible to | |
| investigate unusual conditions <span class="emphasis"><em>without</em></span> the need to restart the Broker. | |
| For instance, you may alter the logging level so that a verbose log is produced whilst an | |
| investigation is in progress and revert the setting later, all without the need to restart the | |
| Broker.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Runtime-Logging-Loggers"></a>9.1.3. Loggers</h3></div></div></div><p>Loggers are responsible for the writing of a log. The log includes log events that match a | |
| Logger's inclusion rules.</p><p>Loggers are associated with either the Broker or a virtualhost. Virtualhost loggers write | |
| only log events related to that virtualhost. Broker Loggers write log events from the Broker | |
| as a whole. Optionally a Broker Logger can be configured to exclude log events coming from | |
| virtualhosts. These abilities can be usefully exploited together in managed service scenarios | |
| to produce separate logs for separate user groups.</p><p>Loggers can be added or removed at runtime, without restarting the Broker. However changes | |
| to a Logger's configuration such as filenames and rolling options don't take effect until the | |
| next restart. Changes to a Logger's inclusion rules take effect immediately.</p><p>All loggers allow the log event layout to be customised. Loggers understand <a class="link" href="http://logback.qos.ch/manual/layouts.html#ClassicPatternLayout" target="_top"> Logback Classic | |
| Pattern Layouts</a>. </p><p>The following sections describes each Logger implementation in detail.</p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="Java-Broker-Runtime-Logging-Loggers-FileLogger"></a>9.1.3.1. FileLogger</h4></div></div></div><p>A <span class="emphasis"><em>FileLogger</em></span> - writes a log file to the filesystem. The name and | |
| location of the log file, the rolling configuration, and compression options can be | |
| configured.</p><p>The <span class="emphasis"><em>roll daily</em></span> option, if enabled, will cause the log file will be | |
| rolled at midnight local time. The rolled over file will have a suffix in the form | |
| <code class="literal">yyyy-mm-dd</code>. In roll daily mode, <span class="emphasis"><em>maximum number of rolled | |
| files</em></span> controls the maximum number of <span class="emphasis"><em>days</em></span> to be retained. | |
| Older files will be deleted.</p><p>The <span class="emphasis"><em>maximum file size</em></span> option limits the size of any one log file. | |
| Once a log file reaches the given size, it will be rolled. The rolled over file will have | |
| the numeric suffix, beginning at <code class="literal">1</code>. If the log file rolls again, first | |
| the existing file with the suffix <code class="literal">.1</code> is renamed to <code class="literal">.2</code> | |
| and so forth. If roll daily is not in use, <span class="emphasis"><em>maximum number of rolled | |
| files</em></span> governs the number of rolled <span class="emphasis"><em>files</em></span> that will be | |
| retained.</p><p><span class="emphasis"><em>Roll on restart</em></span> governs whether the log file is rolled when the | |
| Broker is restarted. If not ticked, the Broker will append to the existing log file until it | |
| needs to be rolled.</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="Java-Broker-Runtime-Logging-Loggers-ConsoleLogger"></a>9.1.3.2. ConsoleLogger</h4></div></div></div><p><span class="emphasis"><em>ConsoleLogger</em></span> - writes a log file standard out or standard | |
| error.</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="Java-Broker-Runtime-Logging-Loggers-SyslogLogger"></a>9.1.3.3. SyslogLogger</h4></div></div></div><p><span class="emphasis"><em>SyslogLogger</em></span> - writes a log file to a syslog daemon using the | |
| <code class="literal">USER</code> facility. The hostname and port number of the syslog daemon can be | |
| configured.</p><p>Log entries can be prefixed with a string. This string defaults to include the word | |
| <code class="literal">Qpid</code> and the name of the Broker or virtualhost. This serves to | |
| distinguish the logging generated by this Qpid instance, from other Qpid instances, or other | |
| applications using the <code class="literal">USER</code>.</p></div><div class="section"><div class="titlepage"><div><div><h4 class="title"><a id="Java-Broker-Runtime-Logging-Loggers-MemoryLogger"></a>9.1.3.4. MemoryLogger</h4></div></div></div><p><span class="emphasis"><em>MemoryLogger</em></span> - writes a log file to a circular in-memory buffer. By | |
| default the circular buffer holds the last 4096 log events. The contents of the buffer can | |
| be viewed via Management. See <a class="xref" href="Java-Broker-Runtime.html#Java-Broker-Runtime-Logging-Management-MemoryLogger" title="Figure 9.3. Viewing a memory logger">Figure 9.3, “Viewing a memory logger”</a></p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Runtime-Logging-InclusionRules"></a>9.1.4. Inclusion Rules</h3></div></div></div><p>A <span class="emphasis"><em>Logger</em></span> has one or more <span class="emphasis"><em>inclusion rules</em></span>. These | |
| govern what appears in the log. A Logger with no inclusion rules will log nothing.</p><p>Inclusion rules can be added, removed or changed at runtime. Changes take place | |
| immediately.</p><p> | |
| </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The <span class="emphasis"><em>Name And Level</em></span> inclusion rule accepts log events that match | |
| a given <span class="emphasis"><em>log event source name</em></span> and have a level that equals or | |
| exceeds the specified value.</p><p>The log event source name refers to the fully qualified class name from which the | |
| event originates. These names permit a trailing wild card <code class="literal">.*</code>. For | |
| instance a source name of <code class="literal">org.apache.qpid.*</code> will match all events | |
| from classes in the package <code class="literal">org.apache.qpid</code> and any sub packages | |
| beneath.</p><p>The <span class="emphasis"><em>Level</em></span> governs the level of the events that will be included | |
| in the log. It may take one of the following values: ERROR, WARN, INFO, DEBUG, TRACE | |
| where ERROR is considered the highest and TRACE the lowest. In addition, there are two | |
| special values: OFF and ALL, the former excludes all log events whereas the latter will | |
| include everything. When considering whether a logging event should be included in the | |
| log, the logging event must have a level that matches that of the inclusion rule or be | |
| higher, otherwise the log event will not appear in the log.</p></li></ul></div><p> | |
| </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Runtime-Logging-Management"></a>9.1.5. Logging Management</h3></div></div></div><p>The logging subsystem can be completely managed from the Web Management Console or the | |
| REST API. You can: </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>Add, remove, or change the configuration of Loggers.</p></li><li class="listitem"><p>Add, remove, or change the Inclusion Rules.</p></li><li class="listitem"><p>For FileLoggers, download the log file and rolled log files associated with | |
| the Logger.</p></li><li class="listitem"><p>For MemoryLoggers, view the last <code class="literal">n</code> log | |
| events</p></li></ul></div><p> | |
| </p><p> The figure that follows shows a FileLogger. The attributes area shows the configuration | |
| of the Logger. The inclusion rule table shows the rules that are associated with the Logger. | |
| The area towards the bottom of the tab allows the log files to be downloaded to the browser. | |
| </p><div class="figure"><a id="Java-Broker-Runtime-Logging-Management-FileLogger"></a><p class="title"><strong>Figure 9.1. Viewing a file logger</strong></p><div class="figure-contents"><div class="mediaobject"><table border="0" style="cellpadding: 0; cellspacing: 0;" summary="manufactured viewport for HTML img" width="900"><tr><td><img alt="Viewing a file logger" src="images/Management-Web-Logging-FileLogger.png" width="900" /></td></tr></table></div></div></div><p><br class="figure-break" /> | |
| </p><p> The figure below shows the editing of the level of an inclusion rule. </p><div class="figure"><a id="Java-Broker-Runtime-Logging-Management-InclusionRule"></a><p class="title"><strong>Figure 9.2. Editing an inclusion rule</strong></p><div class="figure-contents"><div class="mediaobject"><table border="0" style="cellpadding: 0; cellspacing: 0;" summary="manufactured viewport for HTML img" width="900"><tr><td><img alt="Editing an inclusion rule" src="images/Management-Web-Logging-InclusionRule.png" width="900" /></td></tr></table></div></div></div><p><br class="figure-break" /> | |
| </p><p> The figure below shows a Memory Logger. Note that the Memory Logger provides access to | |
| the cached message via the viewer towards the bottom on the tab. </p><div class="figure"><a id="Java-Broker-Runtime-Logging-Management-MemoryLogger"></a><p class="title"><strong>Figure 9.3. Viewing a memory logger</strong></p><div class="figure-contents"><div class="mediaobject"><table border="0" style="cellpadding: 0; cellspacing: 0;" summary="manufactured viewport for HTML img" width="900"><tr><td><img alt="Viewing a memory logger" src="images/Management-Web-Logging-MemoryLogger.png" width="900" /></td></tr></table></div></div></div><p><br class="figure-break" /> | |
| </p></div></div></div><div class="navfooter"><hr /><table summary="Navigation footer" width="100%"><tr><td align="left" width="40%"><a accesskey="p" href="Java-Broker-Security-Configuration-Encryption.html">Prev</a> </td><td align="center" width="20%"> </td><td align="right" width="40%"> <a accesskey="n" href="Java-Broker-Runtime-Disk-Space-Management.html">Next</a></td></tr><tr><td align="left" valign="top" width="40%">8.4. Configuration Encryption </td><td align="center" width="20%"><a accesskey="h" href="Apache-Qpid-Broker-J-Book.html">Home</a></td><td align="right" valign="top" width="40%"> 9.2. Disk Space Management</td></tr></table></div></div> |