org.apache.kafka.streams

Interface StreamsMetrics

@InterfaceStability.Evolving
public interface StreamsMetrics

The Kafka Streams metrics interface for adding metric sensors and collecting metric values.

Method Summary

Modifier and Type	Method and Description
org.apache.kafka.common.metrics.Sensor	addLatencyAndThroughputSensor(String scopeName, String entityName, String operationName, org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel, String... tags) Add a latency and throughput sensor for a specific operation, which will include the following sensors: average latency max latency throughput (num.operations / time unit) Also create a parent sensor with the same metrics that aggregates all entities with the same operation under the same scope if it has not been created.
org.apache.kafka.common.metrics.Sensor	addSensor(String name, org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel) Generic method to create a sensor.
org.apache.kafka.common.metrics.Sensor	addSensor(String name, org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel, org.apache.kafka.common.metrics.Sensor... parents) Generic method to create a sensor with parent sensors.
org.apache.kafka.common.metrics.Sensor	addThroughputSensor(String scopeName, String entityName, String operationName, org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel, String... tags) Add a throughput sensor for a specific operation: throughput (num.operations / time unit) Also create a parent sensor with the same metrics that aggregates all entities with the same operation under the same scope if it has not been created.
Map<MetricName,? extends Metric>	metrics() Get read-only handle on global metrics registry.
void	recordLatency(org.apache.kafka.common.metrics.Sensor sensor, long startNs, long endNs) Record the given latency value of the sensor.
void	recordThroughput(org.apache.kafka.common.metrics.Sensor sensor, long value) Record the throughput value of a sensor.
void	removeSensor(org.apache.kafka.common.metrics.Sensor sensor) Remove a sensor.

Method Detail

metrics

Map<MetricName,? extends Metric> metrics()

Get read-only handle on global metrics registry.

Returns:

Map of all metrics.

addLatencyAndThroughputSensor

org.apache.kafka.common.metrics.Sensor addLatencyAndThroughputSensor(String scopeName,
                                                                     String entityName,
                                                                     String operationName,
                                                                     org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel,
                                                                     String... tags)

Add a latency and throughput sensor for a specific operation, which will include the following sensors:

1. average latency
2. max latency
3. throughput (num.operations / time unit)

Also create a parent sensor with the same metrics that aggregates all entities with the same operation under the same scope if it has not been created.

Parameters:

scopeName - name of the scope, could be the type of the state store, etc.

entityName - name of the entity, could be the name of the state store instance, etc.

operationName - name of the operation, could be get / put / delete / etc.

recordingLevel - the recording level (e.g., INFO or DEBUG) for this sensor.

tags - additional tags of the sensor

Returns:

The added sensor.

recordLatency

void recordLatency(org.apache.kafka.common.metrics.Sensor sensor,
                   long startNs,
                   long endNs)

Record the given latency value of the sensor. If the passed sensor includes throughput metrics, e.g., when created by the addLatencyAndThroughputSensor(String, String, String, Sensor.RecordingLevel, String...) method, then the throughput metrics will also be recorded from this event.

Parameters:

sensor - sensor whose latency we are recording.

startNs - start of measurement time in nanoseconds.

endNs - end of measurement time in nanoseconds.

addThroughputSensor

org.apache.kafka.common.metrics.Sensor addThroughputSensor(String scopeName,
                                                           String entityName,
                                                           String operationName,
                                                           org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel,
                                                           String... tags)

Add a throughput sensor for a specific operation:

1. throughput (num.operations / time unit)

Also create a parent sensor with the same metrics that aggregates all entities with the same operation under the same scope if it has not been created. This sensor is a strict subset of the sensors created by addLatencyAndThroughputSensor(String, String, String, Sensor.RecordingLevel, String...).

Parameters:

scopeName - name of the scope, could be the type of the state store, etc.

entityName - name of the entity, could be the name of the state store instance, etc.

operationName - name of the operation, could be get / put / delete / etc.

recordingLevel - the recording level (e.g., INFO or DEBUG) for this sensor.

tags - additional tags of the sensor

Returns:

The added sensor.

recordThroughput

void recordThroughput(org.apache.kafka.common.metrics.Sensor sensor,
                      long value)

Record the throughput value of a sensor.

Parameters:

sensor - add Sensor whose throughput we are recording

value - throughput value

addSensor

org.apache.kafka.common.metrics.Sensor addSensor(String name,
                                                 org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel)

Generic method to create a sensor. Note that for most cases it is advisable to use addThroughputSensor(String, String, String, Sensor.RecordingLevel, String...) or addLatencyAndThroughputSensor(String, String, String, Sensor.RecordingLevel, String...) to ensure metric name well-formedness and conformity with the rest of the streams code base. However, if the above two methods are not sufficient, this method can also be used.

Parameters:

name - name of the sensor.

recordingLevel - the recording level (e.g., INFO or DEBUG) for this sensor

Returns:

The added sensor.

addSensor

org.apache.kafka.common.metrics.Sensor addSensor(String name,
                                                 org.apache.kafka.common.metrics.Sensor.RecordingLevel recordingLevel,
                                                 org.apache.kafka.common.metrics.Sensor... parents)

Generic method to create a sensor with parent sensors. Note that for most cases it is advisable to use addThroughputSensor(String, String, String, Sensor.RecordingLevel, String...) or addLatencyAndThroughputSensor(String, String, String, Sensor.RecordingLevel, String...) to ensure metric name well-formedness and conformity with the rest of the streams code base. However, if the above two methods are not sufficient, this method can also be used.

Parameters:

name - name of the sensor

recordingLevel - the recording level (e.g., INFO or DEBUG) for this sensor

Returns:

The added sensor.

removeSensor

void removeSensor(org.apache.kafka.common.metrics.Sensor sensor)

Remove a sensor.

Parameters:

sensor - sensor to be removed