This document discusses lessons learned from using serverless functions in production. It begins by defining serverless computing and describing some serverless technologies like AWS Lambda and Backend as a Service. It then details four use cases the author implemented with serverless functions, including video transcoding, data calculations, data fetching, and communication between services. Several issues encountered are explained, such as function timeout errors, database connection problems, and network latency between functions. The document concludes by noting that while some workloads were moved to ECS, most functions remain on AWS Lambda, and that the author continues improving their serverless implementation.

1. Going Serverless
in Production: Lessons Learned

2. ADHY WIRANATA PRASETYO
Technology Lead, HACKTIV8

3. SERVERLESS

4. WHAT
And Why Serverless ?
Serverless computing is a cloud-computing execution
model in which the cloud provider runs the server, and
dynamically manages the allocation of machine resources.
Pricing is based on the actual amount of resources
consumed by an application, rather than on pre-purchased
units of capacity. It can be a form of utility computing.
*stolen shamelessly from wikipedia.

5. WHAT
And Why

6. WHAT
And Why Serverless ?
Run applications / functions without the hassle of
managing the server infrastructure. It’s fully Managed!

7. WHAT
And Why Serverless Technologies
Serverless Compute / Cloud Functions
Backend as a Service
etc...

8. WHAT
And Why Available Options
Serverless Compute / Functions

9. WHAT
And Why JUST DO IT!
We did some readings, but we quickly get our hands dirty
with it.

10. WHAT
And Why JUST DO IT! OOPS..
We did some readings, but we quickly get our hands dirty
with it. We found issues along the way though..

11. WHAT
And Why AWS Lambda?
Functions and Events.
Event triggers a function. Function is just a code that works.
That’s it!

12. WHAT
And Why Sample Lambda Function

13. WHAT
And Why Why AWS Lambda ?

14. WHAT
And Why Why AWS Lambda ?
Zero Provisioning Effort.

15. WHAT
And Why Why AWS Lambda ?
Zero Provisioning Effort. Minimal ops and fully managed!

16. WHAT
And Why Why AWS Lambda ?
Zero Provisioning Effort. Minimal ops and fully managed!
Pay per Use, Infinitely Scalable.

17. WHAT
And Why Why AWS Lambda ?
Zero Provisioning Effort. Minimal ops and fully managed!
Pay per Use, Infinitely Scalable. Your budget.. Most likely
not.

18. WHAT
And Why Why AWS Lambda ?
Zero Provisioning Effort. Minimal ops and fully managed!
Pay per Use, Infinitely Scalable. Your budget.. Most likely
not.
Deliver values faster.

19. WHAT
And Why Why AWS Lambda ?
Zero Provisioning Effort. Minimal ops and fully managed!
Pay per Use, Infinitely Scalable. Your budget.. Most likely
not.
Deliver values faster. Only care for the implementation
code*.
* Baca aturan pakai. Jika pusing berlanjut, jangan hubungi saya.

20. WHAT
And Why Why AWS Lambda ?
Zero Provisioning Effort. Minimal ops and fully managed!
Pay per Use, Infinitely Scalable. Your budget.. Most likely
not.
Deliver values faster. Only care for the implementation
code*.
Sleep.
* Baca aturan pakai. Jika pusing berlanjut, jangan hubungi saya.

21. WHAT
LimitationsAnd Why

22. WHAT
Limitations
15 Minutes invocation time
And Why

23. WHAT
Limitations
15 Minutes invocation time
30 Seconds API Gateway response
And Why

24. WHAT
Limitations
15 Minutes invocation time
30 Seconds API Gateway response
250 MB package size
And Why

25. WHAT
Limitations
15 Minutes invocation time
30 Seconds API Gateway response
250 MB package size
No Persistence, such as DB pooling
And Why

26. WHAT
Limitations
15 Minutes invocation time
30 Seconds API Gateway response
250 MB package size
No Persistence, such as DB pooling
Cold Starts (~0.5seconds in Js)
And Why

27. EXPERIMENTS

28. EXP
Our Cases What we initially expect

29. What we end up with
EXP
Our Cases

30. Our Usage
150+ Lambda Functions (in TypeScript and
Go)
Easy to write!
EXP
Our Cases

31. Our Cases
Video Transcoding
Long-running, Data Calculations
Data Fetching
Communication between Services
EXP
Our Cases

32. Case #1: Video Transcoding
1. Admin is able to upload raw video
2. Service will transcode to multiple
resolutions
3. Notify the admin when transcoding
process finished
EXP
Our Cases

33. Case #1: Video Transcoding
EXP
Our Cases
S3 Bucket (Raw)
User Uploads
to S3
1 2

34. Case #1: Video Transcoding
EXP
Our Cases
S3 Bucket (Raw) Lambda Function
User Uploads
to S3
1 2 3

35. Case #1: Video Transcoding
EXP
Our Cases
S3 Bucket (Raw)
Media Convert
Lambda Function
User Uploads
to S3
1 2 3
4

36. Case #1: Video Transcoding
EXP
Our Cases
S3 Bucket (Raw)
S3 Bucket
Media Convert
Lambda Function
User Uploads
to S3
1 2 3
45

37. Case #1: Video Transcoding
EXP
Our Cases
S3 Bucket (Raw)
S3 Bucket
Media Convert
Lambda Function
User Uploads
to S3
Lambda Function
For Notifications
1 2 3
45
6

38. Case #2: Data Calculation
1. A scheduler which regularly fetches data
from a certain data source
2. A service will do some data calculation
based on the data source and write to
another data store
EXP
Our Cases

39. Case #2: Data Calculation
EXP
Our Cases
Cloudwatch Event
1

40. Case #2: Data Calculation
EXP
Our Cases
Lambda FunctionCloudwatch Event
1 2

41. Case #2: Data Calculation
EXP
Our Cases
Lambda Function PostgreSQL on RDSCloudwatch Event
1 2 3

42. Case #2: Data Calculation
EXP
Our Cases
Lambda Function PostgreSQL on RDSCloudwatch Event
1 2 3
TIMEOUT!

43. Case #2: Data Calculation
Well, we can actually use a recursive for long
running task, but we haven’t tried that method
EXP
Our Cases
Lambda Function PostgreSQL on RDSCloudwatch Event
1 2 3
TIMEOUT!

44. Case #3: Data Fetching
1. Front-End requests a data from API
(REST or GraphQL)
2. Service will connect to database and
return the data as response
EXP
Our Cases

45. Case #3: Data Fetching
EXP
Our Cases
Lambda Function
2
API Gateway
1

46. Case #3: Data Fetching
EXP
Our Cases
Lambda Function
2
API Gateway
1
PostgreSQL on RDS
3

47. Case #3: Data Fetching
EXP
Our Cases
Lambda Function
2
API Gateway
1
PostgreSQL on RDS
3
Cold Start!
DB connections issue

48. Case #4: Comms Between
Services
1. Front End requests data to Service A
2. Service A will do a process, then calls
Service B
3. Service B will be invoked and fetch data
from Database
4. Return the response to Front End
EXP
Our Cases

49. Case #4: Comms Between
Services
EXP
Our Cases
Lambda Function
2
API Gateway
1

50. Case #4: Comms Between
Services
EXP
Our Cases
Lambda Function
2
API Gateway
1
API Gateway
3

51. Case #4: Comms Between
Services
EXP
Our Cases
Lambda Function
2
API Gateway
1
API Gateway
3
Lambda Function
4

52. Case #4: Comms Between
Services
EXP
Our Cases
Lambda Function
2
API Gateway
1
PostgreSQL on RDS
5
API Gateway
3
Lambda Function
4

53. Case #4: Comms Between
Services
EXP
Our Cases
Lambda Function
2
API Gateway
1
PostgreSQL on RDS
5
API Gateway
3
Lambda Function
4
Network Latency!

54. Cost
Pay for API gateway and lambda execution.
Slow functions = 💸🔥
EXP
Our Cases
API Gateway Lambda Function

55. Cost
Pay for API gateway and lambda execution.
Extra wait time for functions = 💸🔥🔥🔥
EXP
Our Cases

56. Code Reusability: Shared Library
We use shared library to reuse codes like utilities or helpers.
Issue: Redeploy functions for each new versions.
EXP
Our Cases
Lambda Function Lambda Function Lambda Function
Shared Code (Library)

57. Code Reusability: Service
We use service to reuse codes as service with synchronous
communication. Issue: network latency, obviously..
EXP
Our Cases
Lambda Function Lambda Function Lambda Function
Shared Code (Lambda Function)

58. Deployment
Using Serverless Framework. You can use SAM template or
Apex UP as well
Tip: Watch out for your deployment bucket. You’ll fill up
your S3 Bucket quickly if you do not set it.
EXP
Our Cases

59. Debugging
EXP
Our Cases

60. Debugging
EXP
Our Cases

61. SUMMARY

62. SUM
Finally So, Are we still using
serverless functions ?
Yes, but not 100%.
We moved some of the heavier workloads to AWS ECS
(Elastic Container Service). Still serverless!
Majority of others still remain in AWS Lambda

63. SUM
Finally Lesson Learned.
We’re not the expert in Serverless technology,
in this case, AWS Lambda. So we did things
wrong in the past.
We’re still improving!

64. ENJOY YOUR PRODUCTIVE DAYS
WITH SERVERLESS!