A talk given on IT Day Kherson on 2018.04.29

1. ? ? ?

2. FROM RUBY TO ELIXIR
IT DAY KHERSON 2018

3. FROM RUBY TO ELIXIR
IT DAY KHERSON 2018

4. Maksym Pugach
Ruby
Ember
React
Elixir

5. Why to develop yet another
language?

7. José Valim Ruby activity

9. Processors stopped getting significantly faster
but they started to scale by getting more cores

10. Multicore world

11. SPARC M8-8 Server
256 x 8 = 2048
hardware
threads

12. Concurrency in

14. The Erlang runtime system is known for its designs that are well suited for systems with the following characteristics:
● Distributed
● Fault-tolerant
● Soft real-time,
● Highly available, non-stop applications
● Hot swapping, where code can be changed without stopping a system
The Erlang programming language is known for the following properties:
● Immutable data
● Pattern matching
● Functional programming

15. + better syntax
+ better error reporting
+ modern tooling
+ can use Erlang libraries
+ fresh enthusiastic community
compiles into EVM bytecode, not into
Erlang first

16. I downloaded elixir last week and started playing ...
It didn't take long, but pretty soon my gut feeling
kicked in.
This is good shit.
- Joe Armstrong
https://joearms.github.io/published/2013-05-31-a-week-with-elixir.html

18. There have to be some code...

20. Comparing Ruby and Elixir…
“When it comes to concurrency
or distributed execution
it feels like the language
is on your side”
- heard somewhere

21. Umbrella applications

23. is
Plug + Phoenix router + MVC project structure
optional
+ Ecto integration
+ Brunch based assets pipeline
+ Phoenix Channels
+ Phoenix Presence

24. about a second to deliver a
Wikipedia article to 2M clients
in a single chat room

25. Phoenix Channels vs Rails Action Cable

26. 2x Digital Ocean 16GB, 8-core instances for the client and server
Rails: 75 rooms, 3750 users Phoenix: 1100 rooms, 55,000 users
(maxed 55,000 client connections)
50 per room

27. 2x Digital Ocean 16GB, 8-core instances for the client and server
Rails: 9 rooms, 1800 users before availability was
compromised when broadcasting.
Phoenix: 275 rooms, 55,000 users (maxed
55,000 client connections)
200 per room

28. Wobserver
by SQUARE ENIX

38. Elixir Stories

39. We’ve also seen an improvement in code clarity. We’re converting our
notifications system from Java to Elixir. The Java version used an Actor
system and weighed in at around 10,000 lines of code. The new Elixir
system has shrunk this to around 1000 lines. The Elixir based system is
also faster and more consistent than the Java one and runs on half the
number of servers.
- Steve Cohen | Pinterest engineer, Data
https://medium.com/@Pinterest_Engineering/introducing-new-open-source-tools-for-the-elixir-community-2f7bb0bb7d8c

40. 87 million unique users (December 2017)
https://blog.discordapp.com/tagged/engineering
● How Discord Scaled Elixir to 5,000,000 Concurrent Users
● How Discord handles push request bursts of over a million per minute with Elixir’s
GenStage

41. 1.5 Billion page views per month
250000 concurrent users at peak
3+ Billion push notifications per month

42. Ruby + $$$ = Elixir
poorly written Ruby application
poorly written Elixir Application
150 Ruby servers < 5 Elixir servers

43. Ruby + $$$ = Elixir
poorly written Ruby application
poorly written Elixir Application
150 Ruby servers < 5 Elixir servers

44. Ruby + $$$ = Elixir
poorly written Ruby application
poorly written Elixir Application
150 Ruby servers < 5 Elixir servers

45. NFL Draft 2016
generally busiest night of the year
200M+ push notifications sent during day one
10x performance from last year
Elixir: not autoscaling needed, just another day

46. ● High-traffic systems
● Systems that do stuff asynchronously
● Distributed / clustered systems
● High-availability systems with true zero-downtime
● Server-side push and real-time applications
● Large applications
● Small microservice
● Your team is used to Elixir already
● A new project where the estimate can handle two weeks
for your team to get productive with a new technology
When to choose Elixir

47. ● The project has short terms and your team is not proficient
with Elixir
● Legacy applications where Operational Expenses are
lower than Development Expenses
When to not choose Elixir

48. elixir-lang.org
As a developer, you should care because with Elixir, you don’t have to give up scalability for fun.
- Bruce Tate CTO of icanmakeitbetter.com
http://icanmakeitbetter.com/icanmakeitbetter-com-and-elixir/

49. one more thing...

51. So, we like Elixir and have seen some pretty big wins with it.
The system that manages rate limits for both the Pinterest
API and Ads API is built in Elixir. Its 50 percent response time
is around 500 microseconds with a 90 percent response time
of 800 microseconds. Yes, microseconds.
- Steve Cohen | Pinterest engineer, Data
https://medium.com/@Pinterest_Engineering/introducing-new-open-source-tools-for-the-elixir-community-2f7bb0bb7d8c