Moving from single tenant to multi tenant

AWS Community Day NL - 2024

Transcript

1. Rearchitecting for scalability: Pubudu Jayawardana Moving a mission critical application from single-tenant to multi-tenant Ryno Marree ACD302 AWS Community Day NL 2024
2. Agenda • What is single-tenancy and multi-tenancy • Use case: at PostNL - Why migrate to multi-tenancy - Migration steps • Results 2
3. 3 Pubudu Senior Solutions Software Engineer @ PostNL Ryno Senior Solutions Software Engineer @ PostNL About Us
4. 4 01 Single-tenancy & Multi-tenancy
5. 5 Flexibility Control Cost-effectiveness Scalability SAAS Resource isolation
6. 6 Single-tenancy vs Multi-tenancy
7. 7 Single-tenancy
8. 8 Single-tenancy • Enhanced security • High resilience • Customizability • Compliance • Troubleshooting Pros
9. 9 Single-tenancy • Higher costs • Scaling challenges • Maintenance is hard • Longer deployment cycles Cons
10. 10 Multi-tenancy
11. 11 Multi-tenancy Pros Cons • Cost efficient • Scalability • Easy to manage • Faster updates • Resource optimization • Security concerns • Compliance is complex • Limited customizations • Noisy neighbour issues
12. 12 02 Use case
13. Mail items per day Parcels per day 1.1 million 6.9 million PostNL in figures - volume 13 End 2023
14. EBE – Event Broker E-Commerce 14
15. EBE – Event Broker E-Commerce 15 ✓ Self-service ✓ Helps decoupling of other applications ✓ Integration as service
16. EBE – Event Broker E-Commerce (Simplified version) 16 PUSH 10M
17. 17 EBE – Single-tenant approach
18. 18 EBE – Single-tenant approach
19. 19 Limitations • Higher deployment time • ~ 8 minutes per stack • ~ 2 hours to update all (even with parallelization) • AWS resource limits • Cloudformation APIs • Code Deploy • API GW • Custom solution to prevent throttling • Cost • Lots of identical resources
20. No downtime Migration: Constraints No action required by the users 20
21. Migration: Multiple stages Producers Consumers HTTPS SQS HTTPS SQS 21
22. Producers: HTTPS Deploying endpoint + API GW deployment No deployments 22
23. Producers: SQS Still use producer specific resources • Access controls – cannot see which AWS account a message came from • We still want alarms per producer 23
24. Quick note: Deployments Simplicity Barebones Complexity Feature rich CloudFormation 24
25. Consumers: Overview 25
26. Consumers: Single-tenant 26
27. "Multi-tenant" consumer 27
28. Migration: Single- to multi-tenant pattern 28
29. Migration: strategy • Events need to be more self-descriptive • Dynamic vs static config o Environment vars vs DynamoDB Bundle Dynamic 29
30. Migration: Strategy • Big bang vs small increments • Many small blue-green or canary deployments • Switching ESM's was safe and easy 30
31. 31 03 Results
32. 32 Results • Faster deployments • Creation of producer/consumer ~1 minute (from 8 minutes) • No re-deploy all • Cost reduction • Code Deploy • Alarms • KMS • Lambda
33. 33 But... what about the cons? In EBE: • No strict compliance requirements • Very little customizations pre producer/consumer • Solutions for noisy neighbours -> ESM concurrency
34. 34 Summary Single-tenancy Multi-tenancy • Limited number of customers • Will not grow fast • Compliance • Customizations • You need to scale
35. 35 Thank you!