问题
My problem is that Storm KafkaSpout stopped to consume messages from Kafka topic after a period of time. When debug is enabled in storm, I get the log file like this:
2016-07-05 03:58:26.097 o.a.s.d.task [INFO] Emitting: packet_spout __metrics [#object[org.apache.storm.metric.api.IMetricsConsumer$TaskInfo 0x2c35b34f "org.apache.storm.metric.api.IMetricsConsumer$TaskInfo@2c35b34f"] [#object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x798f1e35 "[__ack-count = {default=0}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x230867ec "[__sendqueue = {sojourn_time_ms=0.0, write_pos=5411461, read_pos=5411461, overflow=0, arrival_rate_secs=0.0, capacity=1024, population=0}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x7cdec8eb "[__complete-latency = {default=0.0}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x658fc59 "[__skipped-max-spout = 0]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x3c1f3a50 "[__receive = {sojourn_time_ms=4790.5, write_pos=2468305, read_pos=2468304, overflow=0, arrival_rate_secs=0.20874647740319383, capacity=1024, population=1}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x262d7906 "[__skipped-inactive = 0]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x73648c7e "[kafkaPartition = {Partition{host=slave103:9092, topic=packet, partition=12}/fetchAPICallCount=0, Partition{host=slave103:9092, topic=packet, partition=12}/fetchAPILatencyMax=null, Partition{host=slave103:9092, topic=packet, partition=12}/lostMessageCount=0, Partition{host=slave103:9092, topic=packet, partition=12}/fetchAPILatencyMean=null, Partition{host=slave103:9092, topic=packet, partition=12}/fetchAPIMessageCount=0}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x4e43df61 "[kafkaOffset = {packet/totalLatestCompletedOffset=154305947, packet/partition_12/spoutLag=82472754, packet/totalEarliestTimeOffset=233919465, packet/partition_12/earliestTimeOffset=233919465, packet/partition_12/latestEmittedOffset=154307691, packet/partition_12/latestTimeOffset=236778701, packet/totalLatestEmittedOffset=154307691, packet/partition_12/latestCompletedOffset=154305947, packet/totalLatestTimeOffset=236778701, packet/totalSpoutLag=82472754}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x49fe816b "[__transfer-count = {__ack_init=0, default=0, __metrics=0}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x63e2bdc0 "[__fail-count = {}]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x3b17bb7b "[__skipped-throttle = 1086120]"] #object[org.apache.storm.metric.api.IMetricsConsumer$DataPoint 0x1315a68c "[__emit-count = {__ack_init=0, default=0, __metrics=0}]"]]]
2016-07-05 03:58:55.042 o.a.s.d.executor [INFO] Processing received message FOR -2 TUPLE: source: __system:-1, stream: __tick, id: {}, [30]
2016-07-05 03:59:25.042 o.a.s.d.executor [INFO] Processing received message FOR -2 TUPLE: source: __system:-1, stream: __tick, id: {}, [30]
2016-07-05 03:59:25.946 o.a.s.d.executor [INFO] Processing received message FOR -2 TUPLE: source: __system:-1, stream: __metrics_tick, id: {}, [60]
My test topology is really simple, One KafkaSpout and another Counter Bolt. When the topology works fine, the value between FOR and TUPLE is a positive number; when the topology stops to consume the message, the value becomes negative. so I'm curious about what causes the problem of Processing received message FOR -2 TUPLE, and how to fix this problem?
By the way, my experiment environment is:
OS: Red Hat Enterprise Linux Server release 7.0 (Maipo)
Kafka: 0.10.0.0
Storm: 1.0.1
回答1:
With the help from the stom mail list I was able to tune KafkaSpout and resolve the issue. The following settings work for me.
config.put(Config.TOPOLOGY_MAX_SPOUT_PENDING, 2048);
config.put(Config.TOPOLOGY_BACKPRESSURE_ENABLE, false);
config.put(Config.TOPOLOGY_EXECUTOR_RECEIVE_BUFFER_SIZE, 16384);
config.put(Config.TOPOLOGY_EXECUTOR_SEND_BUFFER_SIZE, 16384);
I tested by sending 20k-50k batches with 1sec pause between bursts. Each message was 2048 bytes.
I am running 3 node cluster, my topology has 4 spouts and topic has 64 partitions.
After 200M messages its still working....
回答2:
- Check if the producer is actually writing to the topic you expect.
- Make sure that the spouts can reach Kafka, at the network level. You can check it using Telnet command.
- Can spouts reach Zookeeper? Check it again using Telnet.
Source: KafkaSpout is not receiving anything from Kafka
If above three are true, then:
Kafka has fixed retention window for topics. If the retention is full, it will drop the messages from the tail.
So here what 'might' be happening : the rate at which you are pushing the data to kafka is faster than the rate at which the consumers can consume the messages.
Source : Storm-kafka spout not fast enough to process the information
来源：https://stackoverflow.com/questions/38198961/storm-kafkaspout-stopped-to-consume-messages-from-kafka-topic