JBoss.orgCommunity Documentation
Each mentioned components uses instances of JBoss Cache product for caching in clustered environment. So every element has it's own transport and has to be configured in a proper way. As usual, workspaces have similar configuration but with different cluster-names and may-be some other parameters. The simplest way to configure them is to define their own configuration files for each component in each workspace:
<property name="jbosscache-configuration" value="conf/standalone/test-jbosscache-lock-db1-ws1.xml" />
But if there are few workspaces, configuring them in such a way can be painful and hard-manageable. eXo JCR offers a template-based configuration for JBoss Cache instances. You can have one template for Lock Manager, one for Indexer and one for data container and use them in all the workspaces, defining the map of substitution parameters in a main configuration file. Just simply define ${jbosscache-<parameter name>} inside xml-template and list correct value in JCR configuration file just below "jbosscache-configuration", as shown:
Template:
...
<clustering mode="replication" clusterName="${jbosscache-cluster-name}">
<stateRetrieval timeout="20000" fetchInMemoryState="false" />
...and JCR configuration file:
... <property name="jbosscache-configuration" value="jar:/conf/portal/jbosscache-lock.xml" /> <property name="jbosscache-cluster-name" value="JCR-cluster-locks-db1-ws" /> ...
JGroups is used by JBoss Cache for network communications and transport in a clustered environment. If property "jgroups-configuration" is defined in component configuration, it will be injected into the JBoss Cache instance on startup.
<property name="jgroups-configuration" value="your/path/to/modified-udp.xml" />
As mentioned above, each component (lock manager, data container and query handler) for each workspace requires its own clustered environment. In other words, they have their own clusters with unique names. By default, each cluster should perform multi-casts on a separate port. This configuration leads to much unnecessary overhead on cluster. That's why JGroups offers multiplexer feature, providing ability to use one single channel for set of clusters. This feature reduces network overheads and increase performance and stability of application. To enable multiplexer stack, you should define appropriate configuration file (upd-mux.xml is pre-shipped one with eXo JCR) and set "jgroups-multiplexer-stack" into "true".
<property name="jgroups-configuration" value="jar:/conf/portal/udp-mux.xml" /> <property name="jgroups-multiplexer-stack" value="true" />
eXo JCR implementation is shipped with ready-to-use JBoss Cache configuration templates for JCR's components. They are situated in application package in /conf/porta/ folder.
Data container template is "jbosscache-data.xml":
<?xml version="1.0" encoding="UTF-8"?>
<jbosscache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:jboss:jbosscache-core:config:3.1">
<locking useLockStriping="false" concurrencyLevel="500" lockParentForChildInsertRemove="false"
lockAcquisitionTimeout="20000" />
<clustering mode="replication" clusterName="${jbosscache-cluster-name}">
<stateRetrieval timeout="20000" fetchInMemoryState="false" />
<jgroupsConfig multiplexerStack="jcr.stack" />
<sync />
</clustering>
<!-- Eviction configuration -->
<eviction wakeUpInterval="5000">
<default algorithmClass="org.jboss.cache.eviction.ExpirationAlgorithm"
actionPolicyClass="org.exoplatform.services.jcr.impl.dataflow.persistent.jbosscache.ParentNodeEvictionActionPolicy"
eventQueueSize="1000000">
<property name="maxNodes" value="1000000" />
<property name="warnNoExpirationKey" value="false" />
</default>
</eviction>
</jbosscache>It's template name is "jbosscache-lock.xml"
<?xml version="1.0" encoding="UTF-8"?>
<jbosscache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:jboss:jbosscache-core:config:3.1">
<locking useLockStriping="false" concurrencyLevel="500" lockParentForChildInsertRemove="false"
lockAcquisitionTimeout="20000" />
<clustering mode="replication" clusterName="${jbosscache-cluster-name}">
<stateRetrieval timeout="20000" fetchInMemoryState="false" />
<jgroupsConfig multiplexerStack="jcr.stack" />
<sync />
</clustering>
<loaders passivation="false" shared="true">
<preload>
<node fqn="/" />
</preload>
<loader class="org.exoplatform.services.jcr.impl.core.lock.jbosscache.JDBCCacheLoader" async="false" fetchPersistentState="false"
ignoreModifications="false" purgeOnStartup="false">
<properties>
cache.jdbc.table.name=${jbosscache-cl-cache.jdbc.table.name}
cache.jdbc.table.create=${jbosscache-cl-cache.jdbc.table.create}
cache.jdbc.table.drop=${jbosscache-cl-cache.jdbc.table.drop}
cache.jdbc.table.primarykey=${jbosscache-cl-cache.jdbc.table.primarykey}
cache.jdbc.fqn.column=${jbosscache-cl-cache.jdbc.fqn.column}
cache.jdbc.fqn.type=${jbosscache-cl-cache.jdbc.fqn.type}
cache.jdbc.node.column=${jbosscache-cl-cache.jdbc.node.column}
cache.jdbc.node.type=${jbosscache-cl-cache.jdbc.node.type}
cache.jdbc.parent.column=${jbosscache-cl-cache.jdbc.parent.column}
cache.jdbc.datasource=${jbosscache-cl-cache.jdbc.datasource}
</properties>
</loader>
</loaders>
</jbosscache>To prevent any consistency issue regarding the lock data please ensure that your cache loader is org.exoplatform.services.jcr.impl.core.lock.jbosscache.JDBCCacheLoader and that your database engine is transactional.
Table 22.2. Template variables
| Variable |
|---|
| jbosscache-cluster-name |
| jbosscache-cl-cache.jdbc.table.name |
| jbosscache-cl-cache.jdbc.table.create |
| jbosscache-cl-cache.jdbc.table.drop |
| jbosscache-cl-cache.jdbc.table.primarykey |
| jbosscache-cl-cache.jdbc.fqn.column |
| jbosscache-cl-cache.jdbc.fqn.type |
| jbosscache-cl-cache.jdbc.node.column |
| jbosscache-cl-cache.jdbc.node.type |
| jbosscache-cl-cache.jdbc.parent.column |
| jbosscache-cl-cache.jdbc.datasource |
Have a look at "jbosscache-indexer.xml"
<?xml version="1.0" encoding="UTF-8"?>
<jbosscache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:jboss:jbosscache-core:config:3.1">
<locking useLockStriping="false" concurrencyLevel="500" lockParentForChildInsertRemove="false"
lockAcquisitionTimeout="20000" />
<clustering mode="replication" clusterName="${jbosscache-cluster-name}">
<stateRetrieval timeout="20000" fetchInMemoryState="false" />
<jgroupsConfig multiplexerStack="jcr.stack" />
<sync />
</clustering>
</jbosscache>