Help with configuration

[zigad]

Hi,

I have a question regarding on how to configure the test to run.

I have a RabbitMQ instance and Quarkus application that recieves the event from example "aaa" queue, process it and returns it back to example "bbb" queue. I have predefined exchanges "xxx" and "yyy", binding are made from "xxx" to "aaa" and from "yyy" to "bbb", so i will be using —predeclared option and that is fine.

The question now is how can I configure perf test so that producer will send messages to "xxx" exchange and consume messages from "bbb" queue. I have already setup so messages sent to "xxx" exchange are correct inc headers, but the problem I find is that I cannot specify on what queue the pert test will be consuming processed messages.

Overview of the message flow:

Producer sending to "xxx" exchange -> "xxx" exchange -> bindings route message to "aaa" queue -> Quarkus app -> "yyy" exchange -> bindings route message to "bbb" queue -> Consume and test performance from "bbb" queue.

I tried with something like this but it's not working as expected.
java -jar perf-test-2.18.0.jar --uri "customUri" --producers 1 --consumers 1 —predeclared -e "xxx" -k "customRoutingKey" -mp "customHeaders" --body body.json --predeclared -u "bbb" -z 60

[acogoluegnes]

It may be simpler to start 2 PerfTest instances, one to publish only (-x 1 -y 0) and one to consume only (-x 0 -y 1).

[zigad]

It may be simpler to start 2 PerfTest instances, one to publish only (-x 1 -y 0) and one to consume only (-x 0 -y 1).

Hey, yes I thought about that but I would like to run the performance test to see how well my Quarkus application is performing, not the RabbitMQ instance. I think that if I do it like this I will get metrics for just consumption/production and not throughput of the Quarkus app :/

[acogoluegnes]

Have you tried to use the -u flag to specify the pre-declared queue you want PerfTest to consume from? Note PerfTest expects a specific message content to extract a timestamp and measure latency. You'll have to send back a message that contains the timestamp in the place PerfTest expects.

It may be a bit tricky, see the PerfTest consumer code that extracts the message timestamp to calculate latency (there's an option to use a header to store the timestamp):

rabbitmq-perf-test/src/main/java/com/rabbitmq/perf/Consumer.java

Lines 138 to 154 in 4f3edd1

	if (timestampProvider.isTimestampInHeader()) {
	this.timestampExtractor = (properties, body) -> {
	Object timestamp = properties.getHeaders().get(Producer.TIMESTAMP_HEADER);
	return timestamp == null ? Long.MAX_VALUE : (Long) timestamp;
	};
	} else {
	this.timestampExtractor = (properties, body) -> {
	DataInputStream d = new DataInputStream(new ByteArrayInputStream(body));
	try {
	d.readInt(); // read sequence number
	return d.readLong();
	} catch (IOException e) {
	throw new RuntimeException("Error while extracting timestamp from body");
	}
	};
	}

Routing keys also need to match:

rabbitmq-perf-test/src/main/java/com/rabbitmq/perf/Consumer.java

Lines 281 to 284 in 4f3edd1

	long messageTimestamp = timestampExtractor.apply(properties, body);
	long diff_time = timestampProvider.getDifference(nowTimestamp, messageTimestamp);
	performanceMetrics.received(id.equals(envelope.getRoutingKey()) ? diff_time : 0L);

I've never done it but I think it's possible.

[zigad]

Thanks for this, I'll try it or maybe create a fork and try to modify it to meet my needs.