目录
二. 分层存储监控（Tiered Storage Monitoring）
三. KRaft 监控指标（KRaft Monitoring Metrics）
3.1. KRaft 投票人数监控指标（KRaft Quorum Monitoring Metrics）
3.2. KRaft 控制器监控指标（KRaft Controller Monitoring Metrics）
3.3. KRaft Broker 监控指标（KRaft Broker Monitoring Metrics）
一. 前言
和任何一个分布式系统一样，Kafka 的存储和网络使用情况也是我们需要关注和监控的指标，只有对存储和网络状态进行充分的监控才能及时发现问题并规避风险。
二. 分层存储监控（Tiered Storage Monitoring）
以下一组指标可用于监视分层存储功能：
| METRIC/ATTRIBUTE NAME | DESCRIPTION | MBEAN NAME |
|---|---|---|
| Remote Fetch Bytes Per Sec | Rate of bytes read from remote storage per topic. Omitting 'topic=(...)' will yield the all-topic rate | kafka.server:type=BrokerTopicMetrics, name=RemoteFetchBytesPerSec,topic=([-.\w]+) |
| Remote Fetch Requests Per Sec | Rate of read requests from remote storage per topic. Omitting 'topic=(...)' will yield the all-topic rate | kafka.server:type=BrokerTopicMetrics, name=RemoteFetchRequestsPerSec,topic=([-.\w]+) |
| Remote Fetch Errors Per Sec | Rate of read errors from remote storage per topic. Omitting 'topic=(...)' will yield the all-topic rate | kafka.server:type=BrokerTopicMetrics, name=RemoteFetchErrorsPerSec,topic=([-.\w]+) |
| Remote Copy Bytes Per Sec | Rate of bytes copied to remote storage per topic. Omitting 'topic=(...)' will yield the all-topic rate | kafka.server:type=BrokerTopicMetrics, name=RemoteCopyBytesPerSec,topic=([-.\w]+) |
| Remote Copy Requests Per Sec | Rate of write requests to remote storage per topic. Omitting 'topic=(...)' will yield the all-topic rate | kafka.server:type=BrokerTopicMetrics, name=RemoteCopyRequestsPerSec,topic=([-.\w]+) |
| Remote Copy Errors Per Sec | Rate of write errors from remote storage per topic. Omitting 'topic=(...)' will yield the all-topic rate | kafka.server:type=BrokerTopicMetrics, name=RemoteCopyErrorsPerSec,topic=([-.\w]+) |
| RemoteLogReader Task Queue Size | Size of the queue holding remote storage read tasks | org.apache.kafka.storage.internals.log:type= RemoteStorageThreadPool, name=RemoteLogReaderTaskQueueSize |
| RemoteLogReader Avg Idle Percent | Average idle percent of thread pool for processing remote storage read tasks | org.apache.kafka.storage.internals.log:type= RemoteStorageThreadPool, name=RemoteLogReaderAvgIdlePercent |
| RemoteLogManager Tasks Avg Idle Percent | Average idle percent of thread pool for copying data to remote storage | kafka.log.remote:type=RemoteLogManager, name=RemoteLogManagerTasksAvgIdlePercent |
三. KRaft 监控指标（KRaft Monitoring Metrics）
允许监视 KRaft 投票数和元数据日志的一组度量。
请注意，一些公开的度量取决于 process.roles 定义的节点的角色
3.1. KRaft 投票人数监控指标（KRaft Quorum Monitoring Metrics）
KRaft 集群中的控制器和 Broker 都报告了这些指标：
| METRIC/ATTRIBUTE NAME | DESCRIPTION | MBEAN NAME |
|---|---|---|
| Current State | The current state of this member; possible values are leader, candidate, voted, follower, unattached, observer. | kafka.server:type=raft-metrics,name=current-state |
| Current Leader | The current quorum leader's id; -1 indicates unknown. | kafka.server:type=raft-metrics,name=current-leader |
| Current Voted | The current voted leader's id; -1 indicates not voted for anyone. | kafka.server:type=raft-metrics,name=current-vote |
| Current Epoch | The current quorum epoch. | kafka.server:type=raft-metrics,name=current-epoch |
| High Watermark | The high watermark maintained on this member; -1 if it is unknown. | kafka.server:type=raft-metrics,name=high-watermark |
| Log End Offset | The current raft log end offset. | kafka.server:type=raft-metrics, name=log-end-offset |
| Number of Unknown Voter Connections | Number of unknown voters whose connection information is not cached. This value of this metric is always 0. | kafka.server:type=raft-metrics, name=number-unknown-voter-connections |
| Average Commit Latency | The average time in milliseconds to commit an entry in the raft log. | kafka.server:type=raft-metrics,name=commit-latency-avg |
| Maximum Commit Latency | The maximum time in milliseconds to commit an entry in the raft log. | kafka.server:type=raft-metrics,name=commit-latency-max |
| Average Election Latency | The average time in milliseconds spent on electing a new leader. | kafka.server:type=raft-metrics,name=election-latency-avg |
| Maximum Election Latency | The maximum time in milliseconds spent on electing a new leader. | kafka.server:type=raft-metrics,name=election-latency-max |
| Fetch Records Rate | The average number of records fetched from the leader of the raft quorum. | kafka.server:type=raft-metrics,name=fetch-records-rate |
| Append Records Rate | The average number of records appended per sec by the leader of the raft quorum. | kafka.server:type=raft-metrics,name=append-records-rate |
| Average Poll Idle Ratio | The average fraction of time the client's poll() is idle as opposed to waiting for the user code to process records. | kafka.server:type=raft-metrics, name=poll-idle-ratio-avg |
| Current Metadata Version | Outputs the feature level of the current effective metadata version. | kafka.server:type=MetadataLoader, name=CurrentMetadataVersion |
| Metadata Snapshot Load Count | The total number of times we have loaded a KRaft snapshot since the process was started. | kafka.server:type=MetadataLoader, name=HandleLoadSnapshotCount |
| Latest Metadata Snapshot Size | The total size in bytes of the latest snapshot that the node has generated. If none have been generated yet, this is the size of the latest snapshot that was loaded. If no snapshots have been generated or loaded, this is 0. | kafka.server:type=SnapshotEmitter, name=LatestSnapshotGeneratedBytes |
| Latest Metadata Snapshot Age | The interval in milliseconds since the latest snapshot that the node has generated. If none have been generated yet, this is approximately the time delta since the process was started. | kafka.server:type=SnapshotEmitter, name=LatestSnapshotGeneratedAgeMs |
3.2. KRaft 控制器监控指标（KRaft Controller Monitoring Metrics）
| METRIC/ATTRIBUTE NAME | DESCRIPTION | MBEAN NAME |
|---|---|---|
| Active Controller Count | The number of Active Controllers on this node. Valid values are '0' or '1'. | kafka.controller:type=KafkaController, name=ActiveControllerCount |
| Event Queue Time Ms | A Histogram of the time in milliseconds that requests spent waiting in the Controller Event Queue. | kafka.controller:type=ControllerEventManager, name=EventQueueTimeMs |
| Event Queue Processing Time Ms | A Histogram of the time in milliseconds that requests spent being processed in the Controller Event Queue. | kafka.controller:type=ControllerEventManager, name=EventQueueProcessingTimeMs |
| Fenced Broker Count | The number of fenced brokers as observed by this Controller. | kafka.controller:type=KafkaController, name=FencedBrokerCount |
| Active Broker Count | The number of active brokers as observed by this Controller. | kafka.controller:type=KafkaController, name=ActiveBrokerCount |
| Global Topic Count | The number of global topics as observed by this Controller. | kafka.controller:type=KafkaController, name=GlobalTopicCount |
| Global Partition Count | The number of global partitions as observed by this Controller. | kafka.controller:type=KafkaController, name=GlobalPartitionCount |
| Offline Partition Count | The number of offline topic partitions (non-internal) as observed by this Controller. | kafka.controller:type=KafkaController, name=OfflinePartitionCount |
| Preferred Replica Imbalance Count | The count of topic partitions for which the leader is not the preferred leader. | kafka.controller:type=KafkaController, name=PreferredReplicaImbalanceCount |
| Metadata Error Count | The number of times this controller node has encountered an error during metadata log processing. | kafka.controller:type=KafkaController, name=MetadataErrorCount |
| Last Applied Record Offset | The offset of the last record from the cluster metadata partition that was applied by the Controller. | kafka.controller:type=KafkaController, name=LastAppliedRecordOffset |
| Last Committed Record Offset | The offset of the last record committed to this Controller. | kafka.controller:type=KafkaController, name=LastCommittedRecordOffset |
| Last Applied Record Timestamp | The timestamp of the last record from the cluster metadata partition that was applied by the Controller. | kafka.controller:type=KafkaController, name=LastAppliedRecordTimestamp |
| Last Applied Record Lag Ms | The difference between now and the timestamp of the last record from the cluster metadata partition that was applied by the controller. For active Controllers the value of this lag is always zero. | kafka.controller:type=KafkaController, name=LastAppliedRecordLagMs |
| ZooKeeper Write Behind Lag | The amount of lag in records that ZooKeeper is behind relative to the highest committed record in the metadata log. This metric will only be reported by the active KRaft controller. | kafka.controller:type=KafkaController, name=ZkWriteBehindLag |
| ZooKeeper Metadata Snapshot Write Time | The number of milliseconds the KRaft controller took reconciling a snapshot into ZooKeeper. | kafka.controller:type=KafkaController, name=ZkWriteSnapshotTimeMs |
| ZooKeeper Metadata Delta Write Time | The number of milliseconds the KRaft controller took writing a delta into ZK. | kafka.controller:type=KafkaController, name=ZkWriteDeltaTimeMs |
| Timed-out Broker Heartbeat Count | The number of broker heartbeats that timed out on this controller since the process was started. Note that only active controllers handle heartbeats, so only they will see increases in this metric. | kafka.controller:type=KafkaController, name=TimedOutBrokerHeartbeatCount |
| Number Of Operations Started In Event Queue | The total number of controller event queue operations that were started. This includes deferred operations. | kafka.controller:type=KafkaController, name=EventQueueOperationsStartedCount |
| Number of Operations Timed Out In Event Queue | The total number of controller event queue operations that timed out before they could be performed. | kafka.controller:type=KafkaController, name=EventQueueOperationsTimedOutCount |
| Number Of New Controller Elections | Counts the number of times this node has seen a new controller elected. A transition to the "no leader" state is not counted here. If the same controller as before becomes active, that still counts. | kafka.controller:type=KafkaController, name=NewActiveControllersCount |
3.3. KRaft Broker 监控指标（KRaft Broker Monitoring Metrics）
| METRIC/ATTRIBUTE NAME | DESCRIPTION | MBEAN NAME |
|---|---|---|
| Last Applied Record Offset | The offset of the last record from the cluster metadata partition that was applied by the broker | kafka.server:type=broker-metadata-metrics,name=last-applied-record-offset |
| Last Applied Record Timestamp | The timestamp of the last record from the cluster metadata partition that was applied by the broker. | kafka.server:type=broker-metadata-metrics,name=last-applied-record-timestamp |
| Last Applied Record Lag Ms | The difference between now and the timestamp of the last record from the cluster metadata partition that was applied by the broker | kafka.server:type=broker-metadata-metrics,name=last-applied-record-lag-ms |
| Metadata Load Error Count | The number of errors encountered by the BrokerMetadataListener while loading the metadata log and generating a new MetadataDelta based on it. | kafka.server:type=broker-metadata-metrics,name=metadata-load-error-count |
| Metadata Apply Error Count | The number of errors encountered by the BrokerMetadataPublisher while applying a new MetadataImage based on the latest MetadataDelta. | kafka.server:type=broker-metadata-metrics,name=metadata-apply-error-count |
