Scope of work

• Implement a load test to check how the system performs with 100+ concurrent users, which are sending HTTP requests to the backend.
• Show how the test results need to be interpreted.
• Show which changes need to be done to the system to improve the results of the load test (optional).
• Add enpoints for managing (at least create, read and delete, if there's enough time add update) Blogs, Comments and Authors.
• Refactor the Text-Validator service to be generic.
• Refactor boundry to be reactive.
  • Making the boundry resources of the REST API reactive is out of scope.

Take a look at JMeter here.

Load tests and reports

The load tests are located here:

• for 100 users
• for 1000 users

I tested the following endpoints:

• GET /blog
• POST /blog/{authorId}
• GET /author
• POST /author
• GET /blog/{id}/comment
• POST /blog/{id}/comment/{authorId}

The reporst are located here:

• for 100 users
• for 1000 users
  and should be opened in a browser after locally checking out the repository.

Interpretation

Dashboard Statistics for 100 Users Dashboard Statistics for 1000 Users As can be seen in the above images the difference between the Min and Max Response Times in milliseconds is very big, and increases the more users there are. This implies an inconsistent performance the more users there are.

Response Time Percentiles Chart for 100 Users Response Time Percentiles Chart for 1000 Users

The more GET requests were made, the longer the response times took.

Proposed solutions

• Use the quarkus-hibernate-reactive-panache dependency to use reactive repositories
• Use the quarkus-reactive-mysql-client dependecy to use a reactive SQL client for MySQL
• Add paging so only a limited amount of objects can be fetched per request which should reduced the response time.

For further reading on how to

• implement a reactive Hibernate with Panache using the repository pattern, check here
• implement paging, check here

Used resources

• Apache JMeter documentation
• Quarkus documentation
• Moodle Course Distributed Systems 1
• Moodle Course Distributed Systems 2
• ChatGPT
• StackOverflow
• How to Analyze JMeter Dashboard Reports

How to run the services

To run the production services, execute the following command:

docker-compose --file docker-compose.prod.yaml up -d

The Swagger UI of the Backend Service is available under http://localhost:9090/q/swagger-ui

To verify the functionality of the services create a Blog by using the POST endpoint. The Blogs can be retrieved using the GET endpoint. If the Blog content contains one of the following words bad, invalid or sucks the Blog's valid property will be set to false otherwise it will be set to true.

quarkus-simple-blog

This project uses Quarkus, the Supersonic Subatomic Java Framework.

If you want to learn more about Quarkus, please visit its website: https://quarkus.io/ .

Running the application in dev mode

You can run your application in dev mode that enables live coding using:

./mvnw compile quarkus:dev

NOTE: Quarkus now ships with a Dev UI, which is available in dev mode only at http://localhost:8080/q/dev/.

Packaging and running the application

The application can be packaged using:

./mvnw package

It produces the quarkus-run.jar file in the target/quarkus-app/ directory. Be aware that it’s not an über-jar as the dependencies are copied into the target/quarkus-app/lib/ directory.

The application is now runnable using java -jar target/quarkus-app/quarkus-run.jar.

If you want to build an über-jar, execute the following command:

./mvnw package -Dquarkus.package.type=uber-jar

The application, packaged as an über-jar, is now runnable using java -jar target/*-runner.jar.

Creating a native executable

You can create a native executable using:

./mvnw package -Dnative

Or, if you don't have GraalVM installed, you can run the native executable build in a container using:

./mvnw package -Dnative -Dquarkus.native.container-build=true

You can then execute your native executable with: ./target/quarkus-simple-blog-1.0.0-SNAPSHOT-runner

If you want to learn more about building native executables, please consult https://quarkus.io/guides/maven-tooling.

Related Guides

• SmallRye OpenAPI (guide): Document your REST APIs with OpenAPI - comes with Swagger UI
• Hibernate ORM with Panache (guide): Simplify your persistence code for Hibernate ORM via the active record or the repository pattern
• JDBC Driver - MySQL (guide): Connect to the MySQL database via JDBC