Monitoring¶

The Schema Registry reports a variety of metrics through JMX. It can also be configured to report stats using additional pluggable stats reporters using the metrics.reporters configuration option. The easiest way to view the available metrics is to use jconsole to browse JMX MBeans.

The Schema Registry has two types of metrics. Global metrics help you monitor the overall health of the service. Per-endpoint metrics monitor each API endpoint request method and are prefixed by a name of the endpoint (e.g. subjects.get-schema). These help you understand how the proxy is being used and track down specific performance problems.

Global Metrics¶

MBean: kafka.schema.registry:type=jetty-metrics

connections-active

Total number of active TCP connections.

connections-accepted-rate (deprecated since 2.0)

In 1.x: The average rate per second of accepted TCP connections.

In 2.x: Same as connections-opened-rate.

connections-opened-rate

The average rate per second of opened TCP connections.

connections-closed-rate

The average rate per second of closed TCP connections.

MBean: kafka.schema.registry:type=master-slave-role

master-slave-role

The current role of this Schema Registry instance. A value of 1 indicates this instance is the master, 0 indicates it is a slave.

Per-Endpoint Metrics¶

The following are the metrics available for each endpoint request method. Metrics for all requests are also aggregated into a global instance for each one. These aggregate instances have no prefix in their name.

MBean: kafka.schema.registry:type=jersey-metrics

<endpoint>.request-byte-rate

Bytes/second of incoming requests

<endpoint>.request-error-rate

The average number of requests per second that resulted in HTTP error responses

<endpoint>.request-latency-avg

The average request latency in ms

<endpoint>.request-latency-max

The maximum request latency in ms

<endpoint>.request-rate

The average number of HTTP requests per second.

<endpoint>.request-size-avg

The average request size in bytes

<endpoint>.request-size-max

The maximum request size in bytes

<endpoint>.response-byte-rate

Bytes/second of outgoing responses

<endpoint>.response-rate

The average number of HTTP responses per second.

<endpoint>.response-size-avg

The average response size in bytes

<endpoint>.response-size-max

The maximum response size in bytes

Endpoints¶

The following is a list of all the API endpoint methods. The naming should map intuitively to each of the API operations. To create a full metric name, prefix a per-endpoint metric name with one of these values. For example, to find the rate of GET /brokers API calls, combine the endpoint name brokers.list with the metric name request-rate to get brokers.list.request-rate.

compatibility.subjects.versions.verify POST /compatibility/subjects/{subject}/versions/{version}

schemas.ids.get-schema GET /schemas/ids/{id}

subjects.get-schema POST /subjects/{subject}

subjects.list GET /subjects

subjects.versions.get-schema GET /subjects/{subject}/versions/{version}

subjects.versions.list GET /subjects/{subject}/versions

subjects.versions.register POST /subjects/{subject}/versions