My application is been live from 6 months. The application is host on jboss 7.1 server. From last few days I am finding numerous problem of hanging of jboss server. Though I restart the jboss server again, it does not invoke. I need to restart the server machine itself.

Can anyone please let me know what could be the cause of these problems and the workable resolutions or any suggestion ?

Kindly dont degrade the question as I am facing a lot problems due to this hanging issue.

Also for the information, the application is based on Java, GWT, Hibernate 3.

Please find the standalone.xml file in case if it helps.

<extensions>
    <extension module="org.jboss.as.clustering.infinispan"/>
    <extension module="org.jboss.as.configadmin"/>
    <extension module="org.jboss.as.connector"/>
    <extension module="org.jboss.as.deployment-scanner"/>
    <extension module="org.jboss.as.ee"/>
    <extension module="org.jboss.as.ejb3"/>
    <extension module="org.jboss.as.jaxrs"/>
    <extension module="org.jboss.as.jdr"/>
    <extension module="org.jboss.as.jmx"/>
    <extension module="org.jboss.as.jpa"/>
    <extension module="org.jboss.as.logging"/>
    <extension module="org.jboss.as.mail"/>
    <extension module="org.jboss.as.naming"/>
    <extension module="org.jboss.as.osgi"/>
    <extension module="org.jboss.as.pojo"/>
    <extension module="org.jboss.as.remoting"/>
    <extension module="org.jboss.as.sar"/>
    <extension module="org.jboss.as.security"/>
    <extension module="org.jboss.as.threads"/>
    <extension module="org.jboss.as.transactions"/>
    <extension module="org.jboss.as.web"/>
    <extension module="org.jboss.as.webservices"/>
    <extension module="org.jboss.as.weld"/>
</extensions>

<system-properties>
    <property name="org.apache.coyote.http11.Http11Protocol.COMPRESSION" value="on"/>
    <property name="org.apache.coyote.http11.Http11Protocol.COMPRESSION_MIME_TYPES" value="text/javascript,text/css,text/html,text/xml,text/json"/>
</system-properties>

<management>
    <security-realms>
        <security-realm name="ManagementRealm">
            <authentication>
                <properties path="mgmt-users.properties" relative-to="jboss.server.config.dir"/>
            </authentication>
        </security-realm>
        <security-realm name="ApplicationRealm">
            <authentication>
                <properties path="application-users.properties" relative-to="jboss.server.config.dir"/>
            </authentication>
        </security-realm>
    </security-realms>
    <management-interfaces>
        <native-interface security-realm="ManagementRealm">
            <socket-binding native="management-native"/>
        </native-interface>
        <http-interface security-realm="ManagementRealm">
            <socket-binding http="management-http"/>
        </http-interface>
    </management-interfaces>
</management>

<profile>
    <subsystem xmlns="urn:jboss:domain:logging:1.1">
        <console-handler name="CONSOLE">
            <level name="INFO"/>
            <formatter>
                <pattern-formatter pattern="%d{HH:mm:ss,SSS} %-5p [%c] (%t) %s%E%n"/>
            </formatter>
        </console-handler>
        <periodic-rotating-file-handler name="FILE">
            <formatter>
                <pattern-formatter pattern="%d{HH:mm:ss,SSS} %-5p [%c] (%t) %s%E%n"/>
            </formatter>
            <file relative-to="jboss.server.log.dir" path="server.log"/>
            <suffix value=".yyyy-MM-dd"/>
            <append value="true"/>
        </periodic-rotating-file-handler>
        <logger category="com.arjuna">
            <level name="WARN"/>
        </logger>
        <logger category="org.apache.tomcat.util.modeler">
            <level name="WARN"/>
        </logger>
        <logger category="sun.rmi">
            <level name="WARN"/>
        </logger>
        <logger category="jacorb">
            <level name="WARN"/>
        </logger>
        <logger category="jacorb.config">
            <level name="ERROR"/>
        </logger>
        <root-logger>
            <level name="INFO"/>
            <handlers>
                <handler name="CONSOLE"/>
                <handler name="FILE"/>
            </handlers>
        </root-logger>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:configadmin:1.0"/>
    <subsystem xmlns="urn:jboss:domain:datasources:1.0">
        <datasources>
            <datasource jndi-name="java:jboss/datasources/ExampleDS" pool-name="ExampleDS" enabled="true" use-java-context="true">
                <connection-url>jdbc:h2:mem:test;DB_CLOSE_DELAY=-1</connection-url>
                <driver>h2</driver>
                <security>
                    <user-name>sa</user-name>
                    <password>sa</password>
                </security>
            </datasource>
            <drivers>
                <driver name="h2" module="com.h2database.h2">
                    <xa-datasource-class>org.h2.jdbcx.JdbcDataSource</xa-datasource-class>
                </driver>
            </drivers>
        </datasources>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:deployment-scanner:1.1">
        <deployment-scanner path="deployments" relative-to="jboss.server.base.dir" scan-interval="5000"/>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:ee:1.0"/>
    <subsystem xmlns="urn:jboss:domain:ejb3:1.2">
        <session-bean>
            <stateless>
                <bean-instance-pool-ref pool-name="slsb-strict-max-pool"/>
            </stateless>
            <stateful default-access-timeout="5000" cache-ref="simple"/>
            <singleton default-access-timeout="5000"/>
        </session-bean>
        <pools>
            <bean-instance-pools>
                <strict-max-pool name="slsb-strict-max-pool" max-pool-size="20" instance-acquisition-timeout="5" instance-acquisition-timeout-unit="MINUTES"/>
                <strict-max-pool name="mdb-strict-max-pool" max-pool-size="20" instance-acquisition-timeout="5" instance-acquisition-timeout-unit="MINUTES"/>
            </bean-instance-pools>
        </pools>
        <caches>
            <cache name="simple" aliases="NoPassivationCache"/>
            <cache name="passivating" passivation-store-ref="file" aliases="SimpleStatefulCache"/>
        </caches>
        <passivation-stores>
            <file-passivation-store name="file"/>
        </passivation-stores>
        <async thread-pool-name="default"/>
        <timer-service thread-pool-name="default">
            <data-store path="timer-service-data" relative-to="jboss.server.data.dir"/>
        </timer-service>
        <remote connector-ref="remoting-connector" thread-pool-name="default"/>
        <thread-pools>
            <thread-pool name="default">
                <max-threads count="10"/>
                <keepalive-time time="100" unit="milliseconds"/>
            </thread-pool>
        </thread-pools>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:infinispan:1.2" default-cache-container="hibernate">
        <cache-container name="hibernate" default-cache="local-query">
            <local-cache name="entity">
                <transaction mode="NON_XA"/>
                <eviction strategy="LRU" max-entries="10000"/>
                <expiration max-idle="100000"/>
            </local-cache>
            <local-cache name="local-query">
                <transaction mode="NONE"/>
                <eviction strategy="LRU" max-entries="10000"/>
                <expiration max-idle="100000"/>
            </local-cache>
            <local-cache name="timestamps">
                <transaction mode="NONE"/>
                <eviction strategy="NONE"/>
            </local-cache>
        </cache-container>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:jaxrs:1.0"/>
    <subsystem xmlns="urn:jboss:domain:jca:1.1">
        <archive-validation enabled="true" fail-on-error="true" fail-on-warn="false"/>
        <bean-validation enabled="true"/>
        <default-workmanager>
            <short-running-threads>
                <core-threads count="50"/>
                <queue-length count="50"/>
                <max-threads count="50"/>
                <keepalive-time time="10" unit="seconds"/>
            </short-running-threads>
            <long-running-threads>
                <core-threads count="50"/>
                <queue-length count="50"/>
                <max-threads count="50"/>
                <keepalive-time time="100" unit="seconds"/>
            </long-running-threads>
        </default-workmanager>
        <cached-connection-manager/>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:jdr:1.0"/>
    <subsystem xmlns="urn:jboss:domain:jmx:1.1">
        <show-model value="true"/>
        <remoting-connector/>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:jpa:1.0">
        <jpa default-datasource=""/>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:mail:1.0">
        <mail-session jndi-name="java:jboss/mail/Default">
            <smtp-server outbound-socket-binding-ref="mail-smtp"/>
        </mail-session>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:naming:1.1"/>
    <subsystem xmlns="urn:jboss:domain:osgi:1.2" activation="lazy">
        <properties>
            <property name="org.osgi.framework.startlevel.beginning">
                1
            </property>
        </properties>
        <capabilities>
            <capability name="javax.servlet.api:v25"/>
            <capability name="javax.transaction.api"/>
            <capability name="org.apache.felix.log" startlevel="1"/>
            <capability name="org.jboss.osgi.logging" startlevel="1"/>
            <capability name="org.apache.felix.configadmin" startlevel="1"/>
            <capability name="org.jboss.as.osgi.configadmin" startlevel="1"/>
        </capabilities>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:pojo:1.0"/>
    <subsystem xmlns="urn:jboss:domain:remoting:1.1">
        <connector name="remoting-connector" socket-binding="remoting" security-realm="ApplicationRealm"/>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:resource-adapters:1.0"/>
    <subsystem xmlns="urn:jboss:domain:sar:1.0"/>
    <subsystem xmlns="urn:jboss:domain:security:1.1">
        <security-domains>
            <security-domain name="other" cache-type="default">
                <authentication>
                    <login-module code="Remoting" flag="optional">
                        <module-option name="password-stacking" value="useFirstPass"/>
                    </login-module>
                    <login-module code="RealmUsersRoles" flag="required">
                        <module-option name="usersProperties" value="${jboss.server.config.dir}/application-users.properties"/>
                        <module-option name="rolesProperties" value="${jboss.server.config.dir}/application-roles.properties"/>
                        <module-option name="realm" value="ApplicationRealm"/>
                        <module-option name="password-stacking" value="useFirstPass"/>
                    </login-module>
                </authentication>
            </security-domain>
            <security-domain name="jboss-web-policy" cache-type="default">
                <authorization>
                    <policy-module code="Delegating" flag="required"/>
                </authorization>
            </security-domain>
            <security-domain name="jboss-ejb-policy" cache-type="default">
                <authorization>
                    <policy-module code="Delegating" flag="required"/>
                </authorization>
            </security-domain>
        </security-domains>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:threads:1.1"/>
    <subsystem xmlns="urn:jboss:domain:transactions:1.1">
        <core-environment>
            <process-id>
                <uuid/>
            </process-id>
        </core-environment>
        <recovery-environment socket-binding="txn-recovery-environment" status-socket-binding="txn-status-manager"/>
        <coordinator-environment default-timeout="300"/>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:web:1.1" default-virtual-server="default-host" native="false">
        <connector name="http" protocol="HTTP/1.1" scheme="http" socket-binding="http"/>
        <virtual-server name="default-host" enable-welcome-root="false">
            <alias name="localhost"/>
            <alias name="nextenders.com"/>
        </virtual-server>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:webservices:1.1">
        <modify-wsdl-address>true</modify-wsdl-address>
        <wsdl-host>${jboss.bind.address:127.0.0.1}</wsdl-host>
        <endpoint-config name="Standard-Endpoint-Config"/>
        <endpoint-config name="Recording-Endpoint-Config">
            <pre-handler-chain name="recording-handlers" protocol-bindings="##SOAP11_HTTP ##SOAP11_HTTP_MTOM ##SOAP12_HTTP ##SOAP12_HTTP_MTOM">
                <handler name="RecordingHandler" class="org.jboss.ws.common.invocation.RecordingServerHandler"/>
            </pre-handler-chain>
        </endpoint-config>
    </subsystem>
    <subsystem xmlns="urn:jboss:domain:weld:1.0"/>
</profile>

<interfaces>
    <interface name="management">
        <inet-address value="${jboss.bind.address.management:127.0.0.1}"/>
    </interface>
    <interface name="public">
        <inet-address value="${jboss.bind.address:127.0.0.1}"/>
    </interface>
    <interface name="unsecure">
        <inet-address value="${jboss.bind.address.unsecure:127.0.0.1}"/>
    </interface>
</interfaces>

<socket-binding-group name="standard-sockets" default-interface="public" port-offset="${jboss.socket.binding.port-offset:0}">
    <socket-binding name="management-native" interface="management" port="${jboss.management.native.port:9999}"/>
    <socket-binding name="management-http" interface="management" port="${jboss.management.http.port:9990}"/>
    <socket-binding name="management-https" interface="management" port="${jboss.management.https.port:9443}"/>
    <socket-binding name="ajp" port="8009"/>
    <socket-binding name="http" port="80"/>
    <socket-binding name="https" port="443"/>
    <socket-binding name="osgi-http" interface="management" port="8090"/>
    <socket-binding name="remoting" port="4447"/>
    <socket-binding name="txn-recovery-environment" port="4712"/>
    <socket-binding name="txn-status-manager" port="4713"/>
    <outbound-socket-binding name="mail-smtp">
        <remote-destination host="localhost" port="25"/>
    </outbound-socket-binding>
</socket-binding-group>