Kubernetes. From 0 to Production-Grade with Java

I hear you thinking, “is this yet another session about doing cloud native development?”. Well.. yes, sort of, but we promise it’s going to be a good one - or so we think :).

In this session we’re going to talk (and demo!) about what it means to be a good Cloud Citizen - which is more than merely putting an application in a container and deploying it. To optimize your (Java) application's performance and resilience in the cloud, it is essential to consider factors such as providing real-time health status through fine-grained metrics. You’ll also need to ensure fast startup, and avoid excessive resource consumption within the cluster.
Being a good Cloud Citizen also involves streamlining configuration, deployment and upgrade processes. By integrating these tasks seamlessly, the application can facilitate smooth deployments and upgrades, which will lead to more efficiency and ease of management.

Join us in this session and embark on a journey to develop a perfect(ish) Cloud Native Java Application with Quarkus. This journey will encompass a comprehensive understanding of both the development and operational perspectives, aiming to optimize applications for the cloud environment. You will get an overview of the Kubernetes basics from a Java developer’s perspective and learn step-by-step how to get your application production ready on Kubernetes.

Transcript

1. Kubernetes. Grade with Java Starring
2. Alex Soto (@alexsotob) Who am I ? 2 • @alexsotob • asotobue@redhat.com • Currently Red Hat’s Director of Developer Experience • Featured speaker at technology events • A Java Champion since 2017 • Writer, University Professor, Radio collaborator
3. Kevin Dubois 🤘 Principal Developer Advocate at Red Hat 🤘 International Speaker 🤘 18+ years professional software development experience 🤘 Speak English, Dutch, French, Italian 🤘 Open Source Contributor (Quarkus, Camel, Knative, ..) 🤘 Open Source Community Member (Belgian JUG, Belgian CNCF chapter) @kevindubois@mastodon.social youtube.com/@thekevindubois github.com/kdubois
4. “Kube Native” Java !? @kevindubois @alexsotob
5. “Traditional” • Throughput at the expense of footprint • Long running at expense of startup speed • Rich, dynamic behaviour for mutable systems Kube Native • Throughput solved by scaling • Ephemeral, immutable systems • Footprint and startup speed matter @kevindubois @alexsotob
8. Quarkus + Native (via GraalVM) 12 MB Quarkus + JVM (via OpenJDK) 73 MB Traditional Cloud-Native Stack 136 MB Quarkus + Native (via GraalVM) 0.016 Seconds Quarkus + JVM (via OpenJDK) 0.943 Seconds Traditional Cloud-Native Stack 4.3 Seconds @kevindubois @alexsotob
10. @kevindubois @alexsotob https://developers.redhat.com/articles/2023/09/06/introduction-quarkus-extensions-java-dependencies
11. @kevindubois @alexsotob
12. Kubernetes 12 containers: - name: nginx-container image: nginx:latest ports: - containerPort: 80 volumes: - name: secret-volume secret: secretName: your-secret-name @kevindubois @alexsotob
13. Kubernetes 13 Container Running Sends traffic App not ready @kevindubois @alexsotob
14. Kubernetes 14 After 2.6s (Kafka, Infinispan) App is ready to receive traffic Container Running Sends traffic App not ready @kevindubois
15. Kubernetes 15 Downtime of 2.6s @kevindubois @alexsotob
16. Kubernetes 16 readinessProbe: httpGet: path: /health port: 8080 initialDelaySeconds: 10 periodSeconds: 3 @kevindubois @alexsotob
17. Kubernetes 17 resources: requests: memory: "300Mi" cpu: "250m" # 1/4 core limits: memory: "400Mi" cpu: "1000m" # 1 core @kevindubois @alexsotob
18. Kubernetes 18 CPU Request More CPU Limit
19. Kubernetes 19 Memory Request More Memory Limit
20. Kubernetes 20 Memory Request Limit
21. Kubernetes 21 https://learn.microsoft.com/en-us/azure/developer/java/containers/overview vCPU cores Memory Heap Size GC Replicas 2 4Gb 75% Parallel 2
22. Kubernetes 22 https://learn.microsoft.com/en-us/azure/developer/java/containers/overview resources: requests: memory: "4000Mi" cpu: "2000m" limits: memory: "4000Mi" cpu: "2000m" - env: - name: JDK_JAVA_OPTIONS value: "-XX:+UseParallelGC -XX:MaxRAMPercentage=75"
23. OBSERVABILITY @kevindubois @alexsotob
24. Kubernetes 24 spec: affinity: podAffinity: requiredDuringSchedulingIgnoredDuringExecution: - labelSelector: matchExpressions: - key: "app" operator: In values: - my-app topologyKey: "kubernetes.io/hostname" containers: @kevindubois @alexsotob
25. 25 @kevindubois @alexsotob
26. The application Push to give energy windmill Kafka Topic 2.Sends the interaction Dashboard: Green Energy Nickname Team Push/Tap to generate energy Cars that need energy Two teams competing (top 5 players) First team wins @kevindubois @alexsotob
27. Architecture 3: Generate power (REST) Game Dashboard 1: Assign player Name & Team (REST) 6: Update dashboard (SSE) 2: Increment player cluster counter 4: Send power event 5: Receive power events @kevindubois @alexsotob
28. YOU PLAY! Scan the QR Code with your phone to play @kevindubois @alexsotob
35. Definition 35 @kevindubois @alexsotob
36. What is GitOps? Treat everything as code Git Commands Infrastructure as Code Operations through Git workflows Git Repository Git is the single source of truth @kevindubois @alexsotob
37. 37 Why GitOps? Push Pull Pull Request Source Git Repository Image Registry Config Git Repository Kubernetes Deploy Monitor Detect drift CD Take action @kevindubois @alexsotob
38. 38 @kevindubois @alexsotob
39. 39 V2 Scan the QR Code with your phone to play @kevindubois @alexsotob
40. Free Developer e-Books! developers.redhat.com/e-books @kevindubois @alexsotob
41. http://bit.ly/0ToProdJava
42. Thank you! @thekevindubois kdubois @kevindubois @alexsotob lordofthejars