Most metric values reset each emission period. By default druid emission period is 1 minute, this can be changed by setting the property `druid.monitoring.emissionPeriod`.
|`query/node/time`|Milliseconds taken to query individual historical/realtime processes.|id, status, server.|<1s|
|`query/node/bytes`|number of bytes returned from querying individual historical/realtime processes.|id, status, server.| |
|`query/node/ttfb`|Time to first byte. Milliseconds elapsed until Broker starts receiving the response from individual historical/realtime processes.|id, status, server.|<1s|
|`query/node/backpressure`|Milliseconds that the channel to this process has spent suspended due to backpressure.|id, status, server.| |
|`query/interrupted/count`|number of queries interrupted due to cancellation.|This metric is only available if the QueryCountStatsMonitor module is included.||
|`query/timeout/count`|number of timed out queries.|This metric is only available if the QueryCountStatsMonitor module is included.||
|`query/time`|Milliseconds taken to complete a query.|Common: dataSource, type, interval, hasFilters, duration, context, remoteAddress, id. Aggregation Queries: numMetrics, numComplexMetrics. GroupBy: numDimensions. TopN: threshold, dimension.|<1s|
|`query/segment/time`|Milliseconds taken to query individual segment. Includes time to page in the segment from disk.|id, status, segment.|several hundred milliseconds|
|`query/wait/time`|Milliseconds spent waiting for a segment to be scanned.|id, segment.|<severalhundredmilliseconds|
|`segment/scan/pending`|Number of segments in queue waiting to be scanned.||Close to 0|
|`query/segmentAndCache/time`|Milliseconds taken to query individual segment or hit the cache (if it is enabled on the Historical process).|id, segment.|several hundred milliseconds|
|`query/cpu/time`|Microseconds of CPU time taken to complete a query|Common: dataSource, type, interval, hasFilters, duration, context, remoteAddress, id. Aggregation Queries: numMetrics, numComplexMetrics. GroupBy: numDimensions. TopN: threshold, dimension.|Varies|
|`query/interrupted/count`|number of queries interrupted due to cancellation.|This metric is only available if the QueryCountStatsMonitor module is included.||
|`query/timeout/count`|number of timed out queries.|This metric is only available if the QueryCountStatsMonitor module is included.||
|`query/interrupted/count`|number of queries interrupted due to cancellation.|This metric is only available if the QueryCountStatsMonitor module is included.||
|`query/timeout/count`|number of timed out queries.|This metric is only available if the QueryCountStatsMonitor module is included.||
|`*/put/ok`|Number of new cache entries successfully cached.||Varies, but more than zero.|
|`*/put/error`|Number of new cache entries that could not be cached due to errors.||Varies, but more than zero.|
|`*/put/oversized`|Number of potential new cache entries that were skipped due to being too large (based on `druid.{broker,historical,realtime}.cache.maxEntrySize` properties).||Varies.|
|`query/cache/memcached/total`|Cache metrics unique to memcached (only if `druid.cache.type=memcached`) as their actual values|Variable|N/A|
|`query/cache/memcached/delta`|Cache metrics unique to memcached (only if `druid.cache.type=memcached`) as their delta from the prior event emission|Variable|N/A|
These metrics are applicable for the Kafka Indexing Service.
|Metric|Description|Dimensions|Normal Value|
|------|-----------|----------|------------|
|`ingest/kafka/lag`|Total lag between the offsets consumed by the Kafka indexing tasks and latest offsets in Kafka brokers across all partitions. Minimum emission period for this metric is a minute.|dataSource.|Greater than 0, should not be a very high number |
|`ingest/kafka/maxLag`|Max lag between the offsets consumed by the Kafka indexing tasks and latest offsets in Kafka brokers across all partitions. Minimum emission period for this metric is a minute.|dataSource.|Greater than 0, should not be a very high number |
|`ingest/kafka/avgLag`|Average lag between the offsets consumed by the Kafka indexing tasks and latest offsets in Kafka brokers across all partitions. Minimum emission period for this metric is a minute.|dataSource.|Greater than 0, should not be a very high number |
These metrics are applicable for the Kinesis Indexing Service.
|Metric|Description|Dimensions|Normal Value|
|------|-----------|----------|------------|
|`ingest/kinesis/lag/time`|Total lag time in milliseconds between the current message sequence number consumed by the Kinesis indexing tasks and latest sequence number in Kinesis across all shards. Minimum emission period for this metric is a minute.|dataSource.|Greater than 0, up to max Kinesis retention period in milliseconds |
|`ingest/kinesis/maxLag/time`|Max lag time in milliseconds between the current message sequence number consumed by the Kinesis indexing tasks and latest sequence number in Kinesis across all shards. Minimum emission period for this metric is a minute.|dataSource.|Greater than 0, up to max Kinesis retention period in milliseconds |
|`ingest/kinesis/avgLag/time`|Average lag time in milliseconds between the current message sequence number consumed by the Kinesis indexing tasks and latest sequence number in Kinesis across all shards. Minimum emission period for this metric is a minute.|dataSource.|Greater than 0, up to max Kinesis retention period in milliseconds |
These metrics are only available if the RealtimeMetricsMonitor is included in the monitors list for the Realtime process. These metrics are deltas for each emission period.
|`ingest/events/processed`|Number of events successfully processed per emission period.|dataSource, taskId, taskType.|Equal to your # of events per emission period.|
|`ingest/rows/output`|Number of Druid rows persisted.|dataSource, taskId, taskType.|Your # of events with rollup.|
|`ingest/persists/count`|Number of times persist occurred.|dataSource, taskId, taskType.|Depends on configuration.|
|`ingest/persists/time`|Milliseconds spent doing intermediate persist.|dataSource, taskId, taskType.|Depends on configuration. Generally a few minutes at most.|
|`ingest/persists/cpu`|Cpu time in Nanoseconds spent on doing intermediate persist.|dataSource, taskId, taskType.|Depends on configuration. Generally a few minutes at most.|
|`ingest/persists/backPressure`|Milliseconds spent creating persist tasks and blocking waiting for them to finish.|dataSource, taskId, taskType.|0 or very low|
|`ingest/persists/failed`|Number of persists that failed.|dataSource, taskId, taskType.|0|
|`ingest/handoff/failed`|Number of handoffs that failed.|dataSource, taskId, taskType.|0|
|`ingest/merge/time`|Milliseconds spent merging intermediate segments|dataSource, taskId, taskType.|Depends on configuration. Generally a few minutes at most.|
|`ingest/merge/cpu`|Cpu time in Nanoseconds spent on merging intermediate segments.|dataSource, taskId, taskType.|Depends on configuration. Generally a few minutes at most.|
|`ingest/handoff/count`|Number of handoffs that happened.|dataSource, taskId, taskType.|Varies. Generally greater than 0 once every segment granular period if cluster operating normally|
|`ingest/sink/count`|Number of sinks not handoffed.|dataSource, taskId, taskType.|1~3|
|`ingest/events/messageGap`|Time gap between the data time in event and current system time.|dataSource, taskId, taskType.|Greater than 0, depends on the time carried in event |
|`task/run/time`|Milliseconds taken to run a task.|dataSource, taskId, taskType, taskStatus.|Varies.|
|`task/action/log/time`|Milliseconds taken to log a task action to the audit log.|dataSource, taskId, taskType|<1000(subsecond)|
|`task/action/run/time`|Milliseconds taken to execute a task action.|dataSource, taskId, taskType|Varies from subsecond to a few seconds, based on action type.|
|`segment/added/bytes`|Size in bytes of new segments created.|dataSource, taskId, taskType, interval.|Varies.|
|`segment/moved/bytes`|Size in bytes of segments moved/archived via the Move Task.|dataSource, taskId, taskType, interval.|Varies.|
|`segment/nuked/bytes`|Size in bytes of segments deleted via the Kill Task.|dataSource, taskId, taskType, interval.|Varies.|
|`task/success/count`|Number of successful tasks per emission period. This metric is only available if the TaskCountStatsMonitor module is included.|dataSource.|Varies.|
|`task/failed/count`|Number of failed tasks per emission period. This metric is only available if the TaskCountStatsMonitor module is included.|dataSource.|Varies.|
|`task/running/count`|Number of current running tasks. This metric is only available if the TaskCountStatsMonitor module is included.|dataSource.|Varies.|
|`task/pending/count`|Number of current pending tasks. This metric is only available if the TaskCountStatsMonitor module is included.|dataSource.|Varies.|
|`task/waiting/count`|Number of current waiting tasks. This metric is only available if the TaskCountStatsMonitor module is included.|dataSource.|Varies.|
|`taskSlot/total/count`|Number of total task slots per emission period. This metric is only available if the TaskSlotCountStatsMonitor module is included.| |Varies.|
|`taskSlot/idle/count`|Number of idle task slots per emission period. This metric is only available if the TaskSlotCountStatsMonitor module is included.| |Varies.|
|`taskSlot/used/count`|Number of busy task slots per emission period. This metric is only available if the TaskSlotCountStatsMonitor module is included.| |Varies.|
|`taskSlot/lazy/count`|Number of total task slots in lazy marked MiddleManagers and Indexers per emission period. This metric is only available if the TaskSlotCountStatsMonitor module is included.| |Varies.|
|`taskSlot/blacklisted/count`|Number of total task slots in blacklisted MiddleManagers and Indexers per emission period. This metric is only available if the TaskSlotCountStatsMonitor module is included.| |Varies.|
|`segment/size`|Total size of used segments in a data source. Emitted only for data sources to which at least one used segment belongs.|dataSource.|Varies.|
|`segment/count`|Number of used segments belonging to a data source. Emitted only for data sources to which at least one used segment belongs.|dataSource.|<max|
|`segment/unavailable/count`|Number of segments (not including replicas) left to load until segments that should be loaded in the cluster are available for queries.|dataSource.|0|
|`segment/underReplicated/count`|Number of segments (including replicas) left to load until segments that should be loaded in the cluster are available for queries.|tier, dataSource.|0|
|`compact/task/count`|Number of tasks issued in the auto compaction run.| |Varies.|
|`compactTask/maxSlot/count`|Max number of task slots that can be used for auto compaction tasks in the auto compaction run.| |Varies.|
|`compactTask/availableSlot/count`|Number of available task slots that can be used for auto compaction tasks in the auto compaction run. (this is max slot minus any currently running compaction task)| |Varies.|
|`segment/waitCompact/bytes`|Total bytes of this datasource waiting to be compacted by the auto compaction (only consider intervals/segments that are eligible for auto compaction).|datasource.|Varies.|
|`segment/waitCompact/count`|Total number of segments of this datasource waiting to be compacted by the auto compaction (only consider intervals/segments that are eligible for auto compaction).|datasource.|Varies.|
|`interval/waitCompact/count`|Total number of intervals of this datasource waiting to be compacted by the auto compaction (only consider intervals/segments that are eligible for auto compaction).|datasource.|Varies.|
|`segment/compacted/bytes`|Total bytes of this datasource that are already compacted with the spec set in the auto compaction config.|datasource.|Varies.|
|`segment/compacted/count`|Total number of segments of this datasource that are already compacted with the spec set in the auto compaction config.|datasource.|Varies.|
|`interval/compacted/count`|Total number of intervals of this datasource that are already compacted with the spec set in the auto compaction config.|datasource.|Varies.|
|`segment/skipCompact/bytes`|Total bytes of this datasource that are skipped (not eligible for auto compaction) by the auto compaction.|datasource.|Varies.|
|`segment/skipCompact/count`|Total number of segments of this datasource that are skipped (not eligible for auto compaction) by the auto compaction.|datasource.|Varies.|
|`interval/skipCompact/count`|Total number of intervals of this datasource that are skipped (not eligible for auto compaction) by the auto compaction.|datasource.|Varies.|
|`coordinator/time`|Approximate Coordinator duty runtime in milliseconds. The duty dimension is the string alias of the Duty that is being run.|duty.|Varies.|
|`coordinator/global/time`|Approximate runtime of a full coordination cycle in milliseconds. The `dutyGroup` dimension indicates what type of coordination this run was. i.e. Historical Management vs Indexing|`dutyGroup`|Varies.|
|`metadata/kill/supervisor/count`|Total number of terminated supervisors that were automatically deleted from metadata store per each Coordinator kill supervisor duty run. This metric can help adjust `druid.coordinator.kill.supervisor.durationToRetain` configuration based on whether more or less terminated supervisors need to be deleted per cycle. Note that this metric is only emitted when `druid.coordinator.kill.supervisor.on` is set to true.| |Varies.|
|`metadata/kill/audit/count`|Total number of audit logs that were automatically deleted from metadata store per each Coordinator kill audit duty run. This metric can help adjust `druid.coordinator.kill.audit.durationToRetain` configuration based on whether more or less audit logs need to be deleted per cycle. Note that this metric is only emitted when `druid.coordinator.kill.audit.on` is set to true.| |Varies.|
|`metadata/kill/rule/count`|Total number of rules that were automatically deleted from metadata store per each Coordinator kill rule duty run. This metric can help adjust `druid.coordinator.kill.rule.durationToRetain` configuration based on whether more or less rules need to be deleted per cycle. Note that this metric is only emitted when `druid.coordinator.kill.rule.on` is set to true.| |Varies.|
If `emitBalancingStats` is set to `true` in the Coordinator [dynamic configuration](../configuration/index.md#dynamic-configuration), then [log entries](../configuration/logging.md) for class
|`jvm/gc/cpu`|Count of CPU time in Nanoseconds spent on garbage collection. Note: `jvm/gc/cpu` represents the total time over multiple GC cycles; divide by `jvm/gc/count` to get the mean GC time per cycle|gcName, gcGen|Sum of `jvm/gc/cpu` should be within 10-30% of sum of `jvm/cpu/total`, depending on the GC algorithm used (reported by [`JvmCpuMonitor`](../configuration/index.md#enabling-metrics)) |
|`ingest/events/buffered`|Number of events queued in the EventReceiverFirehose's buffer|serviceName, dataSource, taskId, taskType, bufferCapacity.|Equal to current # of events in the buffer queue.|
|`sys/disk/write/size`|Bytes written to disk. Can we used to determine how much paging is occurring with regards to segments.|fsDevName, fsDirName, fsTypeName, fsSysTypeName, fsOptions.|Varies.|
|`sys/disk/read/size`|Bytes read from disk. Can we used to determine how much paging is occurring with regards to segments.|fsDevName, fsDirName, fsTypeName, fsSysTypeName, fsOptions.|Varies.|