Status

Current state: Under Discussion

Discussion thread: https://lists.apache.org/thread/fvog79tprhk4qybyfs1c0yk0v9j0wffh

JIRA: KAFKA-16810 - Getting issue details... STATUS

Motivation

The kafka-consumer-perf-test tool is a great tool for quickly assessing raw consumer performance. Currently, it subscribes to all partitions and provides an overview of the entire cluster's performance. However, the tool does not support testing the performance of a single broker or partition. Introducing this capability would be highly beneficial for debugging and estimating capacity and resource requirements.

In a real-world scenario, our production environment encountered an issue where a Spark Structured Streaming consumer was experiencing lag. This lag was due to some tasks taking longer to complete. Despite all tasks reading from different partitions with an equal number of records to process, the fetch-time for some partitions was noticeably higher than for others. By modifying the kafka-consumer-perf-test tool to test individual partitions, we were able to isolate the problem to a single broker with a faulty switch.

This modification provided the Hardware team with a straightforward method to conduct experiments and verify resolutions, ultimately streamlining the troubleshooting process and ensuring smoother operations.

Public Interfaces

Add following new optional parameters to kafka-consumer-perf-test:

  • partitions
    List of partitions to fetch data from. Multiple partitions can be provided as a comma-separated list. e.g. --partitions 0,1,2
  • offsets
    List of offsets to start reading from. If specified, the list must have the same number of elements as the partitions list in the same sequence. If not specified, starts reading from earliest unless --from-latest is specified. Only works with --partitions option.

Proposed Changes

As mentioned earlier, two new flags are introduced. When they are specified, consumer will be assigned only specified partitions and seek to provided offsets (If specified). User can specify start offsets to ensure the results are precisely comparable.

Compatibility, Deprecation, and Migration Plan

  • This change is backward compatible since both parameters are optional

Test Plan

The change can be easily tested by specifying new parameters and checking metrics. 

Rejected Alternatives

NA

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