Results for August 7, 2025 testing

Metrics

The metrics shown below come from three separate test runs:

1. Test run CLASSIC uses the CLASSIC group protocol from trunk
2. Test run CONSUMER uses the CONSUMER group protocol, also from trunk
3. Test run CONSUMER (branch) uses the CONSUMER group protocol from my current development branch (KAFKA-19296-revise-wakeups)

Results:

Execution

The test is run on a single AWS instance targeting a six-node cluster. The data on the topic is pre-populated with 100,000,000 messages of 512 bytes each before any of the tests are run. A single “warm up” run of the performance test is executed before executing the three test runs mentioned above.

The command to execute the test is:

kafka-consumer-perf-test.sh \
  --bootstrap-server $BOOTSTRAP_SERVER \
  --topic $TOPIC_NAME \
  --messages $NUM_MESSAGES \
  --consumer.config conf/consumer-$GROUP_PROTOCOL.properties \
  --show-detailed-stats \
  --print-metrics

NUM_MESSAGES is set to 100000000 (100 million).

Client configuration

The consumer configuration sets max.poll.records=5, but is otherwise mostly defaults apart from connectivity/authentication:

bootstrap.servers=$BOOTSTRAP_SERVER
sasl.jaas.config=org.apache.kafka.common.security.plain.PlainLoginModule required
  username="$USER_ID"
  password='$USER_PASSWORD' ;
security.protocol=SASL_SSL
sasl.mechanism=PLAIN
ssl.endpoint.identification.algorithm=
client.dns.lookup=use_all_dns_ips

# Key
max.poll.records=5