Verzögerung beim Konsumieren von Nachrichten in Apache Kafka
Ich benutze Kafka 0.8.0 und versuche, das unten genannte Szenario zu erreichen.
JCA API (Dient als Produzent und sendet Daten an) -----> Consumer ------> HBase
Ich sende jede Nachricht an den Verbraucher, sobald ich die Daten mit dem JCA-Client abrufe. Zum Beispiel, sobald der Produzent die Nachricht Nr. 1 sendet, möchte ich dasselbe vom Konsumenten holen und in HBase 'setzen'. Mein Konsument beginnt jedoch, die Nachrichten nach einigen zufälligen n Nachrichten abzurufen. Ich möchte Produzent und Konsument synchronisieren, damit beide zusammenarbeiten.
Ich habe benutzt:
1 Makler
1 einzelnes Thema
1 einzelner Produzent und hochrangiger Konsument
Kann jemand vorschlagen, was ich tun muss, um das gleiche zu erreichen?
BEARBEITET:
Hinzufügen eines relevanten Code-Snippets.
Consumer.java
public class Consumer extends Thread {
private final ConsumerConnector consumer;
private final String topic;
PrintWriter pw = null;
int t = 0;
StringDecoder kd = new StringDecoder(null);
Map<String, Integer> topicCountMap = new HashMap<String, Integer>();
Map<String, List<KafkaStream<String, Signal>>> consumerMap;
KafkaStream<String, Signal> stream;
ConsumerIterator<String, Signal> it;
public Consumer(String topic) {
consumer = kafka.consumer.Consumer.createJavaConsumerConnector(createConsumerConfig());
this.topic = topic;
topicCountMap.put(topic, new Integer(1));
consumerMap = consumer.createMessageStreams(topicCountMap, kd, new Serializer(
new VerifiableProperties()));
stream = consumerMap.get(topic).get(0);
it = stream.iterator();
}
private static ConsumerConfig createConsumerConfig() {
Properties props = new Properties();
props.put("zookeeper.connect", KafkaProperties.zkConnect);
props.put("group.id", KafkaProperties.groupId);
props.put("zookeeper.session.timeout.ms", "400");
props.put("zookeeper.sync.time.ms", "200");
props.put("auto.commit.interval.ms", "1000");
props.put("fetch.size", "1024");
return new ConsumerConfig(props);
}
synchronized public void run() {
while (it.hasNext()) {
t = (it.next().message()).getChannelid();
System.out.println("In Consumer received msg" + t);
}
}
}
producer.java
public class Producer {
public final kafka.javaapi.producer.Producer<String, Signal> producer;
private final String topic;
private final Properties props = new Properties();
public Producer(String topic)
{
props.put("serializer.class", "org.bigdata.kafka.Serializer");
props.put("key.serializer.class", "kafka.serializer.StringEncoder");
props.put("metadata.broker.list", "localhost:9092");
// Use random partitioner. Don't need the key type. Just set it to Integer.
// The message is of type userdefined Object .
producer = new kafka.javaapi.producer.Producer<String,Signal(newProducerConfig(props));
this.topic = topic;
}
}
KafkaProperties.java
public interface KafkaProperties {
final static String zkConnect = "127.0.0.1:2181";
final static String groupId = "group1";
final static String topic = "test00";
final static String kafkaServerURL = "localhost";
final static int kafkaServerPort = 9092;
final static int kafkaProducerBufferSize = 64 * 1024;
final static int connectionTimeOut = 100000;
final static int reconnectInterval = 10000;
final static String clientId = "SimpleConsumerDemoClient";
}
Auf diese Weise verhält sich der Verbraucher für die ersten 10 Nachrichten, die er nicht empfängt, aber ab der 11. Nachricht funktioniert er ordnungsgemäß.
producer sending msg1
producer sending msg2
producer sending msg3
producer sending msg4
producer sending msg5
producer sending msg6
producer sending msg7
producer sending msg8
producer sending msg9
producer sending msg10
producer sending msg11
producer sending msg12
In Consumer received msg12
producer sending msg13
In Consumer received msg13
producer sending msg14
In Consumer received msg14
producer sending msg15
In Consumer received msg15
producer sending msg16
In Consumer received msg16
producer sending msg17
In Consumer received msg17
producer sending msg18
In Consumer received msg18
producer sending msg19
In Consumer received msg19
producer sending msg20
In Consumer received msg20
producer sending msg21
In Consumer received msg21
BEARBEITET: Hinzufügen der Listener-Funktion, bei der der Produzent Nachrichten an den Konsumenten sendet. Und ich benutze die Standard-Produzentenkonfiguration, habe sie nicht überschrieben
public synchronized void onValueChanged(final MonitorEvent event_) {
// Get the value from the DBR
try {
final DBR dbr = event_.getDBR();
final String[] val = (String[]) dbr.getValue();
producer1.producer.send(new KeyedMessage<String, Signal>
(KafkaProperties.topic,new Signal(messageNo)));
System.out.println("producer sending msg"+messageNo);
messageNo++;
} catch (Exception ex) {
ex.printStackTrace();
}
}