1 Reply Latest reply on Apr 3, 2007 7:57 AM by Ryszard Kozmik

    memory problem with eviction policy

    Suray Philippe Newbie

      Hello all,
      We use JBossCache in a web application to store images (the webapp is a mapping service like google maps).
      TreeCache is started in ServletContextListener.contextInitialized() and stopped in ServletContextListener.contextDestroyed(). In the config file, we specified an eviction policy and a cache loader (see config below).

      <?xml version="1.0" encoding="UTF-8"?>
      <!-- ===================================================================== -->
      <!-- -->
      <!-- Sample TreeCache Service Configuration -->
      <!-- -->
      <!-- ===================================================================== -->
       <classpath codebase="./lib" archives="jboss-cache.jar, jgroups.jar"/>
       <!-- ==================================================================== -->
       <!-- Defines TreeCache configuration -->
       <!-- ==================================================================== -->
       <mbean code="org.jboss.cache.TreeCache" name="jboss.cache:service=TreeCache">
       <!-- Configure the TransactionManager -->
       <attribute name="TransactionManagerLookupClass">org.jboss.cache.BatchModeTransactionManagerLookup</attribute>
       Node locking level : SERIALIZABLE
       REPEATABLE_READ (default)
       <attribute name="IsolationLevel">REPEATABLE_READ</attribute>
       Valid modes are LOCAL
       <attribute name="CacheMode">LOCAL</attribute>
       <attribute name="UseInterceptorMbeans">true</attribute>
       <!-- Name of cluster. Needs to be the same for all clusters, in order
       to find each other
       <attribute name="ClusterName">TreeCache-Cluster</attribute>
       <!-- JGroups protocol stack properties. Can also be a URL,
       e.g. file:/home/bela/default.xml
       <attribute name="ClusterProperties"></attribute>
       <attribute name="ClusterConfig">
       <!-- UDP: if you have a multihomed machine,
       set the bind_addr attribute to the appropriate NIC IP address -->
       <!-- UDP: On Windows machines, because of the media sense feature
       being broken with multicast (even after disabling media sense)
       set the loopback attribute to true -->
       <UDP mcast_addr="" mcast_port="48866"
       ip_ttl="64" ip_mcast="true"
       mcast_send_buf_size="150000" mcast_recv_buf_size="80000"
       ucast_send_buf_size="150000" ucast_recv_buf_size="80000"
       <PING timeout="2000" num_initial_members="3"
       up_thread="false" down_thread="false"/>
       <MERGE2 min_interval="10000" max_interval="20000"/>
       <FD shun="true" up_thread="true" down_thread="true"/>
       <VERIFY_SUSPECT timeout="1500"
       up_thread="false" down_thread="false"/>
       <pbcast.NAKACK gc_lag="50" retransmit_timeout="600,1200,2400,4800"
       max_xmit_size="8192" up_thread="false" down_thread="false"/>
       <UNICAST timeout="600,1200,2400" window_size="100" min_threshold="10"
       <pbcast.STABLE desired_avg_gossip="20000"
       up_thread="false" down_thread="false"/>
       <FRAG frag_size="8192"
       down_thread="false" up_thread="false"/>
       <pbcast.GMS join_timeout="5000" join_retry_timeout="2000"
       shun="true" print_local_addr="true"/>
       <pbcast.STATE_TRANSFER up_thread="false" down_thread="false"/>
       The max amount of time (in milliseconds) we wait until the
       initial state (ie. the contents of the cache) are retrieved from
       existing members in a clustered environment
       <attribute name="InitialStateRetrievalTimeout">20000</attribute>
       Number of milliseconds to wait until all responses for a
       synchronous call have been received.
       <attribute name="SyncReplTimeout">20000</attribute>
       <!-- Max number of milliseconds to wait for a lock acquisition -->
       <attribute name="LockAcquisitionTimeout">15000</attribute>
       <attribute name="EvictionPolicyConfig">
       <attribute name="wakeUpIntervalSeconds">60</attribute>
       <region name="/command_image" policyClass="org.jboss.cache.eviction.LFUPolicy">
       <attribute name="maxNodes">100</attribute>
       <attribute name="minNodes">50</attribute>
       <region name="/command_photo" policyClass="org.jboss.cache.eviction.LFUPolicy">
       <attribute name="maxNodes">80</attribute>
       <attribute name="minNodes">50</attribute>
       <region name="/command_mixte" policyClass="org.jboss.cache.eviction.LFUPolicy">
       <attribute name="maxNodes">80</attribute>
       <attribute name="minNodes">50</attribute>
       Indicate whether to use region based marshalling or not. Set this to true if you are running under a scoped
       class loader, e.g., inside an application server. Default is "false".
       <attribute name="UseRegionBasedMarshalling">false</attribute>
       <attribute name="CacheLoaderConfiguration">
       <!-- if passivation is true, only the first cache loader is used; the rest are ignored -->
       <!-- comma delimited FQNs to preload -->
       <!-- are the cache loaders shared in a cluster? -->
       <!-- we can now have multiple cache loaders, which get chained -->
       <!-- the 'cacheloader' element may be repeated -->
       <!-- same as the old CacheLoaderConfig attribute -->
       <!-- whether the cache loader writes are asynchronous -->
       <!-- only one cache loader in the chain may set fetchPersistentState to true.
       An exception is thrown if more than one cache loader sets this to true. -->
       <!-- determines whether this cache loader ignores writes - defaults to false. -->
       <!-- if set to true, purges the contents of this cache loader when the cache starts up.
       Defaults to false. -->

      When an image is created, we put it in the cache and never remove it because we want that every created image must be kept in the cache.

      We have a problem with memory because she grows and never decreases, i don't understand why the eviction policy does'nt decrease it. We have set passivation parameter to true.

      Thank you for your help.