[KAFKA-16574] The metrics of LogCleaner disappear after reconfiguration

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 3.9.0
• Assignee: Chia-Chuan Yu
• Reporter: Chia-Ping Tsai
• Created: 17/Apr/24 18:35
• Updated: 01/Jun/24 17:02
• Resolved: 01/Jun/24 17:02

Description

see https://github.com/apache/kafka/blob/a3dcbd4e28a35f79f75ec1bf316ef0b39c0df164/core/src/main/scala/kafka/log/LogCleaner.scala#L227

We don't rebuild the metrics after calling shutdown. The following test can prove that.

@Test
def testMetricsAfterReconfiguration(): Unit = {
  val logCleaner = new LogCleaner(new CleanerConfig(true),
    logDirs = Array(TestUtils.tempDir()),
    logs = new Pool[TopicPartition, UnifiedLog](),
    logDirFailureChannel = new LogDirFailureChannel(1),
    time = time)

  def check(): Unit =
    LogCleaner.MetricNames.foreach(name => assertNotNull(KafkaYammerMetrics.defaultRegistry.allMetrics().get(logCleaner.metricsGroup
      .metricName(name, java.util.Collections.emptyMap())), s"$name is gone?"))

  try {
    check()
    logCleaner.reconfigure(new KafkaConfig(TestUtils.createBrokerConfig(1, "localhost:2181")),
      new KafkaConfig(TestUtils.createBrokerConfig(1, "localhost:2181")))
    check()
  } finally logCleaner.shutdown()
} 

Issue Links

• links to: GitHub Pull Request #15863