Monitoring the Kafka Connector using Java Management Extensions (JMX)

This topic describes how to use Java Management Extensions (JMX) to monitor the Snowflake Connector for Kafka. Kafka Connect provides pre-configured JMX metrics that provides information about the Kafka connector. The Snowflake Connector for Kafka provides multiple Managed Beans (MBeans) that you can use to ingest metrics about the Kafka environment. You can load this information into 3rd-party tools, including Prometheus and Grafana.

The JMX feature is enabled in the connector by default. To disable JMX, set the jmx property to false.

Important

Support for JMX is available in version 1.6.0 and later.

In this Topic:

Configuring JMX in the Kafka Connector

JMX is enabled by default in the Snowflake Kafka connector. To enable JMX in Kafka, perform the following:

  1. Enable JMX to connect to your Kafka installation:

    • To make JMX connections to a Kafka installation running on a remote server, set the KAFKA_JMX_OPTS environment variable in your Kafka Connect startup script:

      export KAFKA_JMX_OPTS="-Dcom.sun.management.jmxremote=true
          -Dcom.sun.management.jmxremote.authenticate=false
          -Dcom.sun.management.jmxremote.ssl=false
          -Djava.rmi.server.hostname=<ip_address>
          -Dcom.sun.management.jmxremote.port=<jmx_port>"
      

      Where:

      • ip_address: specifies the IP address of your Kafka Connect installation.

      • jmx_port: specifies the JMX port where Kafka Connect listens for JMX connections.

    • To make JMX connections to Kafka running on the same server, set the JMX_PORT environment variable in your Kafka startup script:

      export JMX_PORT=<port_number>
      

      Where port_number is the JMX port of your Kafka installation.

  2. Restart the Kafka connector.

Using the Snowflake Kafka Connector Managed Beans (MBeans)

JMX uses MBeans to represent objects within Kafka that it can monitor (e.g. thread count, cpu load, etc.). The Snowflake Kafka connector provides MBeans for accessing objects managed by the connector. You can use these MBeans to create monitoring dashboards.

The general format of the Kafka Connector MBean object name is:

snowflake.kafka.connector:connector=connector_name,pipe=pipe_name,category=category_name,name=metric_name

Where:

  • connector=connector_name specifies the name of the connector defined in the Kafka configuration file.

  • pipe=pipe_name specifies the Snowpipe object used to ingest data. The Kafka connector defines Snowpipe objects for each partition.

  • category=category_name specifies the category of the MBean. Each category contains a set of metrics.

  • name=metric_name specifies the name of the metric.

The following sections list the names of the categories and metrics provided by the Snowflake Kafka connector.

Category: file-counts

Metric Name

Data Type

Description

file-count-on-stage

long

The number of files currently on an internal stage. This value is decremented after the process of purging the files has started. This property provides an estimate of how many files are currently on an internal stage.

file-count-on-ingestion

long

The number of files in Snowpipe determined by calling the insertFiles REST API. There is currently a limitation of 5k for files that are being sent via a single REST API request. There is not a one to one relation between the number of files and the number of REST API calls. The number of calls to the insertFiles REST API can be larger than this value. The value of this property is 0 if there are no more files to be ingested.

file-count-table-stage-ingestion-fail

long

The number of files on the table stage that failed ingestion.

file-count-table-stage-broken-record

long

The number of files present on the table stage that corresponds to a broken offset.

file-count-purged

long

The number of files purged from the internal stage after the ingestion status was deteremined.

Category: offsets

Metric Name

Data Type

Description

processed-offset

long

An offset referring to the most recent record sent to the in-memory buffer.

flushed-offset

long

An offset referring to a record that is being flushed on an internal stage after the buffer threshold was reached. The buffer can reach its threshold by time, number of records, or size.

committed-offset

long

An offset referring to a record that has had the precommit API called and has called the Snowpipe insertFiles REST API called.

purged-offset

long

An offset referring to a record that is being purged from the internal stage. This number is the value of the highest recent offset that was purged from the internal stage.

Category: buffer

Metric Name

Data Type

Description

buffer-size-bytes

long

Based on buffer thresholds, returns the buffer size (in bytes) before it is flushed to an internal stage. This value may not be same as the file size since files are compressed when being loaded to an internal stage.

buffer-record-count

long

Based on buffer thresholds, returns the number of Kafka records buffered into memory before the buffer is flushed to an internal stage.

Category: latencies

Metric Name

Data Type

Description

kafka-lag

long

The difference (in seconds) between the time the record is put into Kafka and the time the record is fetched into Kafka Connect. Note that this value can be null if the value was not set inside a record.

commit-lag

long

The difference (in seconds) between the time the file is uploaded to an internal stage and the time the insertFiles REST API is called.

ingestion-lag

long

The difference (in seconds) between the time a file is uploaded to an internal stage and the time the file ingestion status is reported through the insertReport or loadHistoryScan API.