John Roesler created KAFKA-9557: ----------------------------------- Summary: Thread-level "process" metrics are computed incorrectly Key: KAFKA-9557 URL: https://issues.apache.org/jira/browse/KAFKA-9557 Project: Kafka Issue Type: Bug Components: streams Reporter: John Roesler Assignee: John Roesler
Among others, Streams reports the following two thread-level "process" metrics: "process-rate": The average number of process calls per second. "process-total": The total number of process calls across all tasks. See the docs: https://kafka.apache.org/documentation/#kafka_streams_thread_monitoring There's some surprising ambiguity in these definitions that has led to Streams actually reporting something different than what most people would probably expect. Specifically, it's not defined what a "process call" is. A reasonable definition of a "process call" is processing a record or processing a task (both of which are publicly facing concepts, and both of which are the same, since tasks process records one at a time). However, we currently measure number of invocations to a private, internal `process()` method, which would actually process more than one record at a time. Thus, the current metric is under-counting the throughput, in an esoteric and confusing way. Instead, we should simply change the rate and total metrics to measure the (rate and total) of _record_ processing. -- This message was sent by Atlassian Jira (v8.3.4#803005)