[jboss-cvs] JBossAS SVN: r94387 - projects/docs/community/5/Performance_Tuning_Guide/en-US.

[jboss-cvs-commits at lists.jboss.org]

Author: bstansberry at jboss.com
Date: 2009-10-05 14:21:24 -0400 (Mon, 05 Oct 2009)
New Revision: 94387

Modified:
   projects/docs/community/5/Performance_Tuning_Guide/en-US/Performance_Tuning_Guide.xml
Log:
[JBAS-6299] Add JMX discussion to Cluster Performance Tuning Documentation

Modified: projects/docs/community/5/Performance_Tuning_Guide/en-US/Performance_Tuning_Guide.xml
===================================================================
--- projects/docs/community/5/Performance_Tuning_Guide/en-US/Performance_Tuning_Guide.xml	2009-10-05 18:19:53 UTC (rev 94386)
+++ projects/docs/community/5/Performance_Tuning_Guide/en-US/Performance_Tuning_Guide.xml	2009-10-05 18:21:24 UTC (rev 94387)
@@ -517,6 +517,66 @@
          or not the entity type that has been written is itself cached. The cost of these messages can
          easily offset the benefit of query result caching. So, again, be sure to test the effect of caching.</para>
       </section>
+      
+      <section>
+         <title>Monitoring JGroups via JMX</title>
+         <para>When the JBoss AS clustering services create a JGroups <literal>Channel</literal>
+         to use for intra-cluster communication, they also register with the JMX server a number of MBeans related to 
+         that channel; one for the channel itself and one for each of its constituent protocols. For users
+         interested in monitoring the performance-related behavior of a channel, a number of MBean attributes
+         may prove useful.</para>
+         
+         <variablelist>
+            <varlistentry>
+               <term><emphasis role="bold">jboss.jgroups:cluster=&lt;cluster_name&gt;,protocol=UDP,type=protocol</emphasis></term>
+               <listitem>
+               <para>Provides statistical information on the sending and receipt of messages over the network,
+               along with statistics on the behavior of the two thread pools used to carry incoming messages
+               up the channel's protocol stack.</para>
+               <para>Useful attributes directly related to the rate of transmission and receipt include
+               <literal>MessagesSent</literal>, <literal>BytesSent</literal>, <literal>MessagesReceived</literal> and 
+               <literal>BytesReceived</literal>.</para>
+               <para>Useful attributes related to the behavior of the thread pool used to carry ordinary
+               incoming messages up the protocol stack include
+               <literal>IncomingPoolSize</literal> and <literal>IncomingQueueSize</literal>. Equivalent
+               attributes for the pool of threads used to carry special, unordered "out-of-band" messages
+               up the protocol stack include <literal>OOBPoolSize</literal> and <literal>OOBQueueSize</literal>.
+               Note that <literal>OOBQueueSize</literal> will typically be <literal>0</literal> as the standard
+               JGroups configurations do not use a queue for OOB messages.</para>
+               </listitem>
+            </varlistentry>
+            <varlistentry>
+               <term><emphasis role="bold">jboss.jgroups:cluster=&lt;cluster_name&gt;,protocol=UNICAST,type=protocol</emphasis></term>
+               <listitem><para>Provides statistical information on the behavior of the protocol responsible for
+               ensuring lossless, ordered delivery of unicast (i.e. point-to-point) messages.</para>
+               <para>The ratio of <literal>NumRetransmissions</literal> to <literal>MessagesSent</literal>
+               can be tracked to see how frequently messages are not being received by peers and need to be retransmitted.
+               The <literal>NumberOfMessagesInReceiveWindows</literal> attribute can be monitored to track
+               how many messages are queueing up on a receipient node waiting for a message with an earlier
+               sequence number to be received. A high number indicates messages are being dropped and 
+               need to be retransmitted.</para>
+               </listitem>
+            </varlistentry>
+            <varlistentry>
+               <term><emphasis role="bold">jboss.jgroups:cluster=&lt;cluster_name&gt;,protocol=NAKACK,type=protocol</emphasis></term>
+               <listitem><para>Provides statistical information on the behavior of the protocol responsible for
+               ensuring lossless, ordered delivery of multicast (i.e. point-to-multipoint) messages.</para>
+               <para>Use the <literal>XmitRequestsReceived</literal> attribute to track how often a node is being
+               asked to retransmit a messages it sent; use <literal>XmitRequestsSent</literal> to track how
+               often a node is needing to request retransmission of a message.</para>
+               </listitem>
+            </varlistentry>
+            <varlistentry>
+               <term><emphasis role="bold">jboss.jgroups:cluster=&lt;cluster_name&gt;,protocol=FC,type=protocol</emphasis></term>
+               <listitem><para>Provides statistical information on the behavior of the protocol responsible for
+               ensuring fast message senders do not overwhelm slow receivers.</para>
+               <para>Attributes useful for monitoring whether threads seeking to send messages are having to
+               block while waiting for credits from receivers include <literal>Blockings</literal>, 
+               <literal>AverageTimeBlocked</literal> and <literal>TotalTimeBlocked</literal>.</para>
+               </listitem>
+            </varlistentry>
+         </variablelist>
+      </section>
    </section>
 		
 		<section>