JBoss.orgCommunity Documentation

Chapter 23. LockManager configuration

23.1. Introduction
23.2. LockManagerImpl
23.3. CacheableLockManagerImpl
23.3.1. Configuration
23.3.2. Simple JbossCache Configuraion
23.3.3. Template JBossCache Configuration
23.3.4. Data Types in Different Databases

What LockManager does?

In general, LockManager stores lock objects, so it can give Lock object or can release it, etc.

Also, LockManager is responsible for removing Locks that live too long. This parameter may be configured with "time-out" property.

JCR provide two base implementation of LockManager:

In this article, we will talk mostly about CacheableLockManagerImpl.

You can enable LockManager by adding lock-manager-configuration to workspace-configuration.

For example:

<workspace name="ws">
   ...
   <lock-manager class="org.exoplatform.services.jcr.impl.core.lock.jbosscache.CacheableLockManagerImpl">
      <properties>
         <property name="time-out" value="15m" />
         ...
      </properties>
   </lock-manager>               
   ...
</workspace>

LockManagerImpl is simple implementation of LockManager, and also faster than CacheableLockManager. It stores Lock objects in HashMap and may also persist Locks if LockPersister is configured. LockManagerImpl does not support replication in any way.

See more about LockManager Configuration at here.

CacheableLockManagerImpl stores Lock object in JBoss-cache, so Locks are replicable and affects on cluster, not only a single node. Also JBoss-cache has JDBCCacheLoader, so locks will be stored to database.

Both implementation supports Expired Locks removing. There is LockRemover - separate thread, that periodically ask LockManager for Locks that live much and must be removed. So, timeout for LockRemover may be set as follows, default value is 30m.

<properties>
   <property name="time-out" value="10m" />
   ...
</properties>

Replication requirements are the same for Cache

You can see a full JCR configuration example at here.

Common tips:

  • clusterName ("jbosscache-cluster-name") must be unique;

  • cache.jdbc.table.name must be unique per datasource;

  • cache.jdbc.fqn.type must and cache.jdbc.node.type must be configured according to used database;

There is a few ways to configure CacheableLockManagerImpl, and all of them configure JBoss-cache and JDBCCacheLoader.

See http://community.jboss.org/wiki/JBossCacheJDBCCacheLoader

First one is - put JbossCache configuraion file path to CacheableLockManagerImpl

Config is:

<lock-manager class="org.exoplatform.services.jcr.impl.core.lock.jbosscache.CacheableLockManagerImpl">
   <properties>
     <property name="time-out" value="15m" />
     <property name="jbosscache-configuration" value="conf/standalone/cluster/test-jbosscache-lock-config.xml" />
   </properties>
</lock-manager>

test-jbosscache-lock-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<jbosscache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:jboss:jbosscache-core:config:3.2">

 <locking useLockStriping="false" concurrencyLevel="50000" lockParentForChildInsertRemove="false" lockAcquisitionTimeout="20000" />

 <clustering mode="replication" clusterName="JBoss-Cache-Lock-Cluster_Name">
  <stateRetrieval timeout="20000" fetchInMemoryState="false" nonBlocking="true" />
  <jgroupsConfig>

   <TCP bind_addr="127.0.0.1" start_port="9800" loopback="true" recv_buf_size="20000000" send_buf_size="640000" discard_incompatible_packets="true"
    max_bundle_size="64000" max_bundle_timeout="30" use_incoming_packet_handler="true" enable_bundling="false" use_send_queues="false" sock_conn_timeout="300"
    skip_suspected_members="true" use_concurrent_stack="true" thread_pool.enabled="true" thread_pool.min_threads="1" thread_pool.max_threads="25"
    thread_pool.keep_alive_time="5000" thread_pool.queue_enabled="false" thread_pool.queue_max_size="100" thread_pool.rejection_policy="run"
    oob_thread_pool.enabled="true" oob_thread_pool.min_threads="1" oob_thread_pool.max_threads="8" oob_thread_pool.keep_alive_time="5000"
    oob_thread_pool.queue_enabled="false" oob_thread_pool.queue_max_size="100" oob_thread_pool.rejection_policy="run" />
   <MPING timeout="2000" num_initial_members="2" mcast_port="34540" bind_addr="127.0.0.1" mcast_addr="224.0.0.1" />


   <MERGE2 max_interval="30000" min_interval="10000" />
   <FD_SOCK />
   <FD max_tries="5" shun="true" timeout="10000" />
   <VERIFY_SUSPECT timeout="1500" />
   <pbcast.NAKACK discard_delivered_msgs="true" gc_lag="0" retransmit_timeout="300,600,1200,2400,4800" use_mcast_xmit="false" />
   <UNICAST timeout="300,600,1200,2400,3600" />
   <pbcast.STABLE desired_avg_gossip="50000" max_bytes="400000" stability_delay="1000" />
   <pbcast.GMS join_timeout="5000" print_local_addr="true" shun="false" view_ack_collection_timeout="5000" view_bundling="true" />
   <FRAG2 frag_size="60000" />
   <pbcast.STREAMING_STATE_TRANSFER />
  <pbcast.FLUSH timeout="0" />

  </jgroupsConfig

  <sync />
 </clustering>

 <loaders passivation="false" shared="true">
  <preload>
   <node fqn="/" />
  </preload>
  <loader class="org.jboss.cache.loader.JDBCCacheLoader" async="false" fetchPersistentState="false" ignoreModifications="false" purgeOnStartup="false">
   <properties>
    cache.jdbc.table.name=jcrlocks_ws
    cache.jdbc.table.create=true
    cache.jdbc.table.drop=false
    cache.jdbc.table.primarykey=jcrlocks_ws_pk
    cache.jdbc.fqn.column=fqn
    cache.jdbc.fqn.type=VARCHAR(512)
    cache.jdbc.node.column=node
    cache.jdbc.node.type=<BLOB>  
    cache.jdbc.parent.column=parent
    cache.jdbc.datasource=jdbcjcr
   </properties>
  </loader>

 </loaders>

</jbosscache>

Configuration requirements:

Second one is using template JBoss-cache configuration for all LockManagers

Lock template configuration

test-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="50000" 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">
      <!-- All the data of the JCR locks needs to be loaded at startup -->
      <preload>
         <node fqn="/" />
      </preload>  
      <!--
      For another cache-loader class you should use another template with
      cache-loader specific parameters
      ->
      <loader class="org.jboss.cache.loader.JDBCCacheLoader" async=q"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>

As you see, all configurable paramaters are filled by templates and will be replaced by LockManagers conf parameters:

<lock-manager class="org.exoplatform.services.jcr.impl.core.lock.jbosscache.CacheableLockManagerImpl">
   <properties>
      <property name="time-out" value="15m" />
      <property name="jbosscache-configuration" value="test-jbosscache-lock.xml" />
      <property name="jgroups-configuration" value="udp-mux.xml" />
      <property name="jgroups-multiplexer-stack" value="true" />
      <property name="jbosscache-cluster-name" value="JCR-cluster-locks-ws" />
      <property name="jbosscache-cl-cache.jdbc.table.name" value="jcrlocks_ws" />
      <property name="jbosscache-cl-cache.jdbc.table.create" value="true" />
      <property name="jbosscache-cl-cache.jdbc.table.drop" value="false" />
      <property name="jbosscache-cl-cache.jdbc.table.primarykey" value="jcrlocks_ws_pk" />
      <property name="jbosscache-cl-cache.jdbc.fqn.column" value="fqn" />
      <property name="jbosscache-cl-cache.jdbc.fqn.type" value="AUTO"/>
      <property name="jbosscache-cl-cache.jdbc.node.column" value="node" />
      <property name="jbosscache-cl-cache.jdbc.node.type" value="AUTO"/>
      <property name="jbosscache-cl-cache.jdbc.parent.column" value="parent" />
      <property name="jbosscache-cl-cache.jdbc.datasource" value="jdbcjcr" />
   </properties>
</lock-manager>

Configuration requirements:

our-udp-mux.xml

<protocol_stacks>
   <stack name="jcr.stack">
      <config>
         <UDP mcast_addr="228.10.10.10" mcast_port="45588" tos="8" ucast_recv_buf_size="20000000"
            ucast_send_buf_size="640000" mcast_recv_buf_size="25000000" mcast_send_buf_size="640000" loopback="false"
            discard_incompatible_packets="true" max_bundle_size="64000" max_bundle_timeout="30"
            use_incoming_packet_handler="true" ip_ttl="2" enable_bundling="true" enable_diagnostics="true"
            thread_naming_pattern="cl" use_concurrent_stack="true" thread_pool.enabled="true" thread_pool.min_threads="2"
            thread_pool.max_threads="8" thread_pool.keep_alive_time="5000" thread_pool.queue_enabled="true"
            thread_pool.queue_max_size="1000" thread_pool.rejection_policy="discard" oob_thread_pool.enabled="true"
            oob_thread_pool.min_threads="1" oob_thread_pool.max_threads="8" oob_thread_pool.keep_alive_time="5000"
            oob_thread_pool.queue_enabled="false" oob_thread_pool.queue_max_size="100" oob_thread_pool.rejection_policy="Run" />

         <PING timeout="2000" num_initial_members="3" />
         <MERGE2 max_interval="30000" min_interval="10000" />
         <FD_SOCK />
         <FD timeout="10000" max_tries="5" shun="true" />
         <VERIFY_SUSPECT timeout="1500" />
         <BARRIER />
         <pbcast.NAKACK use_stats_for_retransmission="false" exponential_backoff="150" use_mcast_xmit="true"
            gc_lag="0" retransmit_timeout="50,300,600,1200" discard_delivered_msgs="true" />
         <UNICAST timeout="300,600,1200" />
         <pbcast.STABLE stability_delay="1000" desired_avg_gossip="50000" max_bytes="1000000" />
         <VIEW_SYNC avg_send_interval="60000" />
         <pbcast.GMS print_local_addr="true" join_timeout="3000" shun="false" view_bundling="true" />
         <FC max_credits="500000" min_threshold="0.20" />
         <FRAG2 frag_size="60000" />
         <!--pbcast.STREAMING_STATE_TRANSFER /-->
         <pbcast.STATE_TRANSFER />
         <!-- pbcast.FLUSH  /-->
      </config>
   </stack>
</protocol_stacks>