THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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Status
Current state: "Under Discussion" Accepted
Discussion thread: here
JIRA: KAFKA-5746
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| ApiKey | Scope of error | Request:Errors Mapping |
|---|---|---|
| UpdateMetadata | request | 1:1 |
| ControlledShutdown | request | 1:1 |
| FindCoordinator | request | 1:1 |
| JoinGroup | request | 1:1 |
| Heartbeat | request | 1:1 |
| LeaveGroup | request | 1:1 |
| SyncGroup | request | 1:1 |
| ListGroups | request | 1:1 |
| SaslHandshake | request | 1:1 |
| ApiVersions | request | 1:1 |
| InitProducerId | request | 1:1 |
| AddOffsetsToTxn | request | 1:1 |
| EndTxn | request | 1:1 |
| DescribeAcls | request | 1:1 |
| Produce | partition | 1:n |
| Fetch | partition | 1:n |
| Offsets | partition | 1:n |
| OffsetCommit | partition | 1:n |
| OffsetFetch | partition | 1:n |
| DeleteRecords | partition | 1:n |
| OffsetForLeaderEpoch | partition | 1:n |
| AddPartitionsToTxn | partition | 1:n |
| WriteTxnMarkers | partition | 1:n |
| TxnOffsetCommit | partition | 1:n |
| LeaderAndIsr | partition + request | 1:n |
| StopReplica | partition + request | 1:n |
| Metadata | topic | 1:n |
| CreateTopics | topic | 1:n |
| DeleteTopics | topic | 1:n |
| DescribeGroups | group | 1:n |
| CreateAcls | acl | 1:n |
| DeleteAcls | acl | 1:n |
| DescribeConfigs | resource | 1:n |
| AlterConfigs | resource | 1:n |
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Message conversion rate and time
Down conversions are expensive since the whole response has to be read into memory for conversion. It will be useful to monitor the rate of down conversion and the time spent on conversions.
Fetch down and produce message conversion rate rates will be a meter meters in the same group as existing topic metrics TotalFetchRequestsPerSec etc.
MBean: kafka.server:type=BrokerTopicMetrics,name=FetchMessageConversionsPerSec,topic=([-.\w]+)
MBean: kafka.server:type=BrokerTopicMetrics,name=FetchDownConversionsPerSecProduceMessageConversionsPerSec,topic=([-.\w]+)
It will also be useful to know the time taken for down conversions. Fetch down conversion time metric will be a histogram in the same groupalongside other request time metrics. This time will also be included in request logs so that clients requiring expensive down conversions can be identified. Conversion time will also be added for produce requests.
MBean: kafka.servernetwork:type=BrokerTopicMetricsRequestMetrics,name=FetchDownConversionsTimeMsMessageConversionsTimeMs,topic=([-.\w]+)
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request={Produce|Fetch}
Request size and temporary memory size
Large messages can cause GC issues in the broker, especially if down conversions are required. Maximum message batch size can be configured per topic to control this, but that is the size after compression. Since the batches are decompressed to validate produce requests and for fetch downconversiondown conversion, it will be useful to have topic metrics for produce message batch size.
Topic Request metrics will be added for request size as well as the temporary memory size for processing the request. These two metrics will be histograms. For produce messages the two metrics will indicate message batch size before and after decompression as well as the compression ratio. The two sizes will give an indication of compression ratio as well. These two metrics will be histograms.
values will also be included in request logs so that clients requiring a lot of temporary memory space can be identified.
MBean: kafka.servernetwork:type=BrokerTopicMetricsRequestMetrics,name=ProduceBatchSizeRequestBytes,topic=([-.\w]+)request=<apiKey>
MBean: kafka.servernetwork:type=BrokerTopicMetricsRequestMetrics,name=ProduceUncompressedBatchSizeTemporaryMemoryBytes,topic=([-.\w]+)request=<apiKey>
Authentication success and failure rates
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- successful-authentication-rate
- failed-authentication-rate
ZooKeeper status and latency
It will be good to monitor latency of ZooKeeper requests so that any issues with ZooKeeper communication can be detected early.
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MBean: kafka.server:type=ZooKeeperClientMetrics,name=ZooKeeperLatencyZooKeeperRequestLatencyMs
It will also be useful to see the current status of broker's connection to ZooKeeper.
This will be a String Gauge in the existing group SessionExpireListener which currently shows the rate of each state (eg. DisconnectsPerSec)
MBean: kafka.server:type=SessionExpireListener,name=SessionState
State will be one of Disconnected|SyncConnected|AuthFailed|ConnectedReadOnly|SaslAuthenticated|Expired
Client-side metrics
Client versions
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