Thinking in Actors

Using Erlang style actors to implement a highly concurrent system. Presented on WebCampZg (http://2014.webcampzg.org/).

Transcript

2. Thinking in Actors @sasajuric
5. CPU CPU CPU CPU CPU CPU CPU CPU
6. bank account balance http request socket database connection
7. “deposit”, 300 “store”, account_id, ... http request bank account database ok ok
8. bank account balance “deposit”, 300 “withdraw”, 200 “balance”
9. defmodule BankAccount do use ExActor.GenServer definit do initial_state(0) end defcast deposit(amount), state: balance do new_state(balance + amount) end defcast deposit(amount), state: balance do if amount <= balance do new_state(balance – amount) else new_state(balance) end end defcall balance, state: balance do reply(balance) end end
10. account = find_account(id) BankAccount.withdraw(account,200) account = find_account(id) BankAccount.deposit(account,300) account = find_account(id) balance = BankAccount.balance(account) client 1 client 2 client 3 account = BankAccount.start
11. http http bg job http clients accounts database
12. > 30 active events > 5,000 simultaneous players > 2,000 requests/sec
13. 1.accept TCP packets 2.assemble XML messages 3.update the model 4.store to database 5.serialize the model 6.dispatch
14. tcp listener xml assembler model builder serializer persister dispatcher
15. tcp listener xml assembler model builder serializer persister dispatcher message 6 message 5 message 4 message 3 message 2 message 1
16. tcp listener xml assembler model builder serializer persister dispatcher
17. persister tcp listener xml assembler model builder serializer dispatcher
18. <message> <match id=”1” ...> ... </match> <match id=”2” ...> ... </match> ... <match id=”n” ...> ... </match> </message>
19. i model builder serializer dispatcher match 1 match 2 match 3 match 4 match 5
20. i
21. i match 1 match 2 match 3 match 4 match 5
22. player match http request subscription notification query new messages
23. http://www.manning.com/juric/ wcp14twcf