I have an application running Kafka consumers and want to monitor the processing time of each message consumed from the topic. The application is a Spring boot application and exposes Kafka consumer metrics to Spring Actuator Prometheus endpoint using micrometre registry.
Can I use kafka_consumer_commit_latency_avg_seconds or kafka_consumer_commit_latency_max_seconds to monitor or alert?
Those metrics have nothing to do with record processing time. spring-kafka provides metrics for that; see here.
Monitoring Listener Performance
Starting with version 2.3, the listener container will automatically create and update Micrometer Timer s for the listener, if Micrometer is detected on the class path, and a single MeterRegistry is present in the application context. The timers can be disabled by setting the ContainerProperty micrometerEnabled to false.
Two timers are maintained - one for successful calls to the listener and one for >failures.
Related
How can I connect my Springboot application to Kafka topic as soon as the application start,
so that when send method is invoked there is no need to fetch the metadata information?
Kafka clients are required to do an initial metadata fetch to determine the leader broker to actually send the data, but this shouldn't drastically change the startup time of any application and wouldn't prevent you from calling any Kafka producer actions
How health indicators should be properly configured for Spring Boot service running on top of Kafka Streams with DB connection? We use Spring Cloud Streams and Kafka Streams binding, Spring-Data JPA, Kubernetes as a container hypervisor. We have let say 3 service replicas and 9 partitions for each topic. A typical service usually joins messages from two topics and persist data in a database and publish data back to another kafka topic.
After switching to Spring Boot 2.3.1 and changing K8s liveness/readiness endpoints to the new ones:
/actuator/health/liveness
/actuator/health/readiness
we discovered that by default they do not have any health indicators included.
According to documentation:
Actuator configures the "liveness" and "readiness" probes as Health
Groups; this means that all the Health Groups features are available
for them. (...) By default, Spring Boot does not add other Health
Indicators to these groups.
I believe that this is the right approach, but I have not tested that:
management.endpoint.health.group.readiness.include: readinessState,db,binders
management.endpoint.health.group.liveness.include: livenessState,ping,diskSpace
We try to cover the following use cases:
rolling update: not available consumption slot (idle instance) when new replica is added
stream has died (runtime exception has been thrown)
DB is not available during container start up / when service is running
broker is not available
I have found a similar question, however I believe the current one is specifically related to Kafka services. They are different in it's nature from REST services.
Update:
In spring boot 2.3.1 binders health indicator checks if streams are in RUNNING or REBALANCING state for Kafka 2.5 (before only RUNNING), so I guess that rolling update case with idle instance is handled by its logic.
I'm using Spring boot version 1.5.4.RELEASE & spring Kafka version 1.3.8.RELEASE.
Some generic questions
is there way to find out no more messages in topic/partition in
consumer
how to start consumer to start consuming messages from a
topic only after writing from the producer is done?
Spring Boot 1.5 is end of life and no longer supported; the current version is 2.2.5.
The latest 1.3.x version of Spring for Apache Kafka is 1.3.10. It will only be supported through the end of this year.
You should plan on upgrading.
You can start and stop containers using the KafkaListenerEndpointRegistry bean; set autoStartup to false on the container factory.
See Detecting Idle and Non-Responsive Consumers.
While efficient, one problem with asynchronous consumers is detecting when they are idle - users might want to take some action if no messages arrive for some period of time.
You can configure the listener container to publish a ListenerContainerIdleEvent when some time passes with no message delivery. While the container is idle, an event will be published every idleEventInterval milliseconds.
...
In my POC, I am using Spring Cloud Config and Spring Stream Rabbit. I want to dynamically change number of listeners (concurrency). Is it possible to do that? I want to do following:
1) If there are too many messages in queue, i want to increase concurrency level.
2) In scenario where my downstream system is not available, I want to stop processing messages from queue (in short concurrency level 0).
How i can achieve this?
Thanks for help.
The listener container running in the binder supports such changes (although you can't go down to 0, but the container can be stop() ped).
However, spring-cloud-stream provides no mechanism for you to get a reference to the listener container.
You might want to consider using a #RabbitListener from Spring AMQP instead - it will give you complete control over the listener container.
Application Data Flow:
JSon Messages--> Active MQ --> Spring XD-- Business Login(Transform JSon to Java Object)--> Save Data to Target DB--> DB.
Question:
Sprin-Xd is running in cluster mode, configured with Radis.
Spring XD picks up the message from the Active message queue(AMQ). So message is no longer in AMQ. Now while one of the containers where this message is being processed with some business logic suddenly goes down. In this scenarios-
Will Spring-XD framework automatically re-process that particular message ? what's mechanism behind that?
Thanks,
Abhi
Not with a Redis transport; Redis has no infrastructure to support such a requirement ("transactional" reads). You would need to use a rabbit or kafka transport.
EDIT:
See Application Configuration (scroll down to RabbitMQ) and Message Bus Configuration.
Specifically, the default ackMode is AUTO which means messages are acknowledged on success.