ActiveMQ KahaDB always locking and waiting
I am trying to use ActiveMQ in a relatively simple work queue use case. I have one queue, and have a simple Producer and Consumer. My question is what am I doing wrong that continuously makes the DB lock? here is the message I get continously:
14/04/05 18:14:13 INFO store.SharedFileLocker: Database activemq-data\localhost\KahaDB\lock is locked... waiting 10 seconds for the database to be unlocked. Reason: java.io.IOException: File 'activemq-data\localhost\KahaDB\lock' could not be locked.
I am running the producer and consumer in separate threads at the same time. Initially, I had the connection at the class level, so I thought that was the problem, but even creating the connection from scratch every call to put and get still causes locking.
I have done research but have failed to find a solution. I am running ActiveMQ 5.9.0 on windows 7.
Here is what prints out when I start it via cmd prompt:
C:\activemq\apache-activemq-5.9.0\bin>activemq
Java Runtime: Oracle Corporation 1.7.0_40 C:\Program Files\Java\jre7
Heap sizes: current=1005568k free=995061k max=1005568k
JVM args: -Dcom.sun.management.jmxremote -Xms1G -Xmx1G -Djava.util.logging.config.file=logging.properties -Dhawtio.realm=activemq -Dhawtio.role=admins -Dhawtio.rolePrincipalCla
vemq.jaas.GroupPrincipal -Djava.security.auth.login.config=C:\activemq\apache-activemq-5.9.0\bin\..\conf\login.config -Dactivemq.classpath=C:\activemq\apache-activemq-5.9.0\bin\..\
che-activemq-5.9.0\bin\../conf;C:\activemq\apache-activemq-5.9.0\bin\../conf; -Dactivemq.home=C:\activemq\apache-activemq-5.9.0\bin\.. -Dactivemq.base=C:\activemq\apache-activemq-5
mq.conf=C:\activemq\apache-activemq-5.9.0\bin\..\conf -Dactivemq.data=C:\activemq\apache-activemq-5.9.0\bin\..\data -Djava.io.tmpdir=C:\activemq\apache-activemq-5.9.0\bin\..\data\t
Extensions classpath:
[C:\activemq\apache-activemq-5.9.0\bin\..\lib,C:\activemq\apache-activemq-5.9.0\bin\..\lib\camel,C:\activemq\apache-activemq-5.9.0\bin\..\lib\optional,C:\activemq\apache-activemq
b,C:\activemq\apache-activemq-5.9.0\bin\..\lib\extra]
ACTIVEMQ_HOME: C:\activemq\apache-activemq-5.9.0\bin\..
ACTIVEMQ_BASE: C:\activemq\apache-activemq-5.9.0\bin\..
ACTIVEMQ_CONF: C:\activemq\apache-activemq-5.9.0\bin\..\conf
ACTIVEMQ_DATA: C:\activemq\apache-activemq-5.9.0\bin\..\data
Loading message broker from: xbean:activemq.xml
INFO | Refreshing org.apache.activemq.xbean.XBeanBrokerFactory$1@5bf2a8f5: startup date [Sat Apr 05 17:42:42 EDT 2014]; root of context hierarchy
INFO | PListStore:[C:\activemq\apache-activemq-5.9.0\bin\..\data\localhost\tmp_storage] started
INFO | Using Persistence Adapter: KahaDBPersistenceAdapter[C:\activemq\apache-activemq-5.9.0\bin\..\data\kahadb]
INFO | KahaDB is version 5
INFO | Recovering from the journal ...
INFO | Recovery replayed 6935 operations from the journal in 0.416 seconds.
INFO | Apache ActiveMQ 5.9.0 (localhost, ID:Owner-PC-49614-1396734165637-0:1) is starting
INFO | Listening for connections at: tcp://Owner-PC:61616?maximumConnections=1000&wireFormat.maxFrameSize=104857600
INFO | Connector openwire started
INFO | Listening for connections at: amqp://Owner-PC:5673?maximumConnections=1000&wireFormat.maxFrameSize=104857600
INFO | Connector amqp started
INFO | Listening for connections at: stomp://Owner-PC:61613?maximumConnections=1000&wireFormat.maxFrameSize=104857600
INFO | Connector stomp started
INFO | Listening for connections at: mqtt://Owner-PC:1883?maximumConnections=1000&wireFormat.maxFrameSize=104857600
INFO | Connector mqtt started
INFO | Listening for connections at ws://Owner-PC:61614?maximumConnections=1000&wireFormat.maxFrameSize=104857600
INFO | Connector ws started
INFO | Apache ActiveMQ 5.9.0 (localhost, ID:Owner-PC-49614-1396734165637-0:1) started
INFO | For help or more information please see: http://activemq.apache.org
INFO | Welcome to hawtio 1.2-M23 : http://hawt.io/ : Don't cha wish your console was hawt like me? ;-)
INFO | Starting hawtio authentication filter, JAAS realm: "activemq" authorized role: "admins" role principal classes: "org.apache.activemq.jaas.GroupPrincipal"
INFO | Using file upload directory: C:\activemq\apache-activemq-5.9.0\bin\..\data\tmp\uploads
INFO | jolokia-agent: Using access restrictor classpath:/jolokia-access.xml
INFO | ActiveMQ WebConsole available at http://localhost:8161/
INFO | Initializing Spring FrameworkServlet 'dispatcher'
Here is my java to implement the Queue as ActiveMQ (I have a Queue interface and this is an Impl)
import com.google.gson.Gson;
import java.util.Set;
import javax.jms.Connection;
import javax.jms.DeliveryMode;
import javax.jms.Destination;
import javax.jms.ExceptionListener;
import javax.jms.JMSException;
import javax.jms.MessageConsumer;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;
import org.apache.activemq.ActiveMQConnectionFactory;
public class ActiveMQImpl implements Queue, ExceptionListener {
private String host;
private String user;
private String pw;
public void init() {
}
public void close() {
}
public Message get() {
Message outMessage = null;
ActiveMQConnectionFactory connectionFactory = null;
Connection connection = null;
try {
if (connection == null) {
connectionFactory = new ActiveMQConnectionFactory("vm://localhost");
// Create a Connection
connection = connectionFactory.createConnection();
}
connection.start();
// Create a Session
Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the destination (Topic or Queue)
Destination destination = session.createQueue("work");
// Create a MessageConsumer from the Session to the Topic or Queue
MessageConsumer consumer = session.createConsumer(destination);
// Wait for a message
javax.jms.Message message = consumer.receive(1000);
if (message instanceof TextMessage) {
TextMessage textMessage = (TextMessage) message;
String text = textMessage.getText();
outMessage = new Gson().fromJson(text, Message.class);
// System.out.println("Received: " + text);
} else {
// System.out.println("Received: " + message);
}
consumer.close();
// session.commit();
session.close();
//connection.close();
} catch (Exception e) {
System.out.println("Caught: " + e);
e.printStackTrace();
}
return outMessage;
}
public void put(Message inMessage) {
try {
ActiveMQConnectionFactory connectionFactory = null;
Connection prodConnection = null;
connectionFactory = new ActiveMQConnectionFactory("vm://localhost");
prodConnection = connectionFactory.createConnection();
prodConnection.start();
Session session = prodConnection.createSession(false, Session.AUTO_ACKNOWLEDGE);
Destination destination = session.createQueue("work");
MessageProducer producer = session.createProducer(destination);
producer.setDeliveryMode(DeliveryMode.PERSISTENT);
producer.setTimeToLive(60000);
// Create a messages
String text = inMessage.toString();
TextMessage message = session.createTextMessage(text);
// Tell the producer to send the message
System.out.println("Sent message: " + text);
producer.send(message);
producer.close();
// session.commit();
session.close();
prodConnection.close();
} catch (Exception e) {
System.out.println("Caught: " + e);
onException(null);
e.printStackTrace();
}
}
public void onException(JMSException jmse) {
//send this to the error channel object...
System.out.println(jmse);
}
public void put(Set<Message> messages) {
try {
ActiveMQConnectionFactory connectionFactory=null;
Connection connection=null;
Connection prodConnection=null;
if (connection == null) {
connectionFactory = new ActiveMQConnectionFactory("vm://localhost?jms.useAsyncSend=true");
// Create a Connection
connection = connectionFactory.createConnection("admin", "admin");
}
connection.start();
// Create a Session
Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
// Create the destination (Topic or Queue)
Destination destination = session.createQueue("work");
// Create a MessageProducer from the Session to the Topic or Queue
MessageProducer producer = session.createProducer(destination);
producer.setDeliveryMode(DeliveryMode.PERSISTENT);
// Create a messages
for (Message inMessage : messages) {
String text = inMessage.toString();
TextMessage message = session.createTextMessage(text);
// Tell the producer to send the message
System.out.println("Sent message: " + text);
producer.send(message);
}
producer.close();
// session.commit();
session.close();
//connection.close();
} catch (Exception e) {
System.out.println("Caught: " + e);
onException(null);
e.printStackTrace();
}
}
}
Here are the producers and consumers (simple debugging classes)
public class Producer {
public static void main(String[] args) {
Queue q = QueueFactory.create(QueueType.ACTIVEMQ);
try {
for (int i = 0; i < 10; i++) {
q.put(new Message("testimpl" + i, "whatever", i));
Thread.sleep(1000);
}
} catch (InterruptedException ex) {
Logger.getLogger(Producer.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
public class Consumer {
public static void main(String[] args) {
Queue q = QueueFactory.create(QueueType.ACTIVEMQ);
try {
while (true) {
Message get = q.get();
System.out.println(get);
Thread.sleep(1000);
}
} catch (InterruptedException ex) {
Logger.getLogger(Consumer.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
any help is appreciated.
Answer
do following
kill java process for active mq, open task manager -> go to process -> check for java -> and right click and say end process
then go to <activemq_install_directory>/data/kahadb
and delete lock file which gets generated
try starting activemq again
for me this works every time I face this issue