This project serves as a playground for trying out monitoring options for both single noded and clustered (sharded) Akka applications.

The application itself is a simulation of Conveyor Sorting Subsystem and its original code (without monitoring and using older Akka version) can be found in akka-sharding-example repository.

To build the application, use build_docker.sh script, which uses sbt to build the fat jar and docker-compose to build the image.

This project uses Prometheus as monitoring solution. You can run both the application (single noded) and Prometheus using Docker Compose that is included in the project. Execute docker-compose up and go to localhost:9090 to see Prometheus GUI.

We can generate lots of HTTP requests using these tools:

• ab - Apache HTTP server benchmarking tool,
• parallel - GNU Parallel - The Command-Line Power Tool,
• haproxy - fast and reliable http reverse proxy and load balancer,
• provided URLs.txt for single-noded app,
• provided shardedURLs.txt and haproxy.conf.

You can install these tools manually or using install_load_test_tools.sh script.

Just run SingleNodedApp from your IDE or sbt runSingle and then:

cat src/main/resources/URLs.txt | parallel -j 5 'ab -ql -n 2000 -c 1 -k {}' | grep 'Requests per second'

You can run two nodes by executing:

• first node: sbt runSharded
• second node: sbt '; set javaOptions += "-Dclustering.port=2552" ; set javaOptions += "-Dapplication.exposed-port=8081" ; set javaOptions += "-Dmetrics.enabled=false" ; runSharded'

We want to balance the traffic between the two nodes. Simple configuration for haproxy daemon can be found in resources dir. Run it with: haproxy -f src/main/resources/haproxy.conf

This will set up a round-robing load balancer with frontend on port 8000 and backends on 8080 and 8081. You can then use different shardedURLs.txt file:

cat src/main/resources/shardedURLs.txt | parallel -j 5 'ab -ql -n 2000 -c 1 -k {}' | grep 'Requests per second'

You can generate Flame Graphs for specified Java PIDs (use jps to find out the PID) by executing generate_flamegraph.sh script.