ボツにしたスライド。

1. (loose|tight)
couplings in Erlang
4th Tokyo Erlang Workshop
in Aoyama, 2010/2/26
@kuenishi
http://creativecommons.org/licenses/by-sa/2.1/jp/

3. S O A

4. SOA :

11. tightly coupled loosely coupled
generalized
Pros fast failure separation
extensible
specialized
Cons failure companion slow
less extensible

12. fast
tightly
ideal
coupled
standard
specialized
loosely
useless
coupled
slow

13. BERT/BERT-RPC
Erlang Serialization Specs,
with extended specs for RPC,
--{call, Module, Function, Arguments}
--> {reply, { some, term, Value }}
Binary ERlang Term,
Older than any of below;
Thrift, Protocol Buffers, Avro,
MsgPack...

14. BERT/BERT-RPC cont’d
Older than any of below;
Thrift, Protocol Buffers, Avro,
MsgPack...
Various Implementations
C++, Clojure, Erlang, Factor (?),
Go, Haskell, JavaScript, Python,
Ruby, Scala.

15. How to use BERT in C
#include “ei.h”
INCLUDES= -I$(EI)/include
LDFLAGS= -L$(EI)/lib -lei
EILIB= `code:lib_dir(erl_interface).`
erl_interface.h is deprecated.

16. Erlang -> Java
JInterface,
included in OTP release package by
default,
vice versa.

17. C -> Erlang
C node,
CORBA (no way!),
any other loose-coupling interface.

18. Erlang -> C
With BERT,
There are 4 ways->
C node,
Port Driver,
Linked-in Driver,
NIF.

19. C node
A process behaves like an Erlang node,
BERT/TCP connected,
Failure doesn’t involve the other.
main(){
... TCP Erlang
C node
... node
}

20. Port Driver
==Popen3,
BERT/stdin/stdout connected,
tolerant for Child process’ failure.
fork/exec
stdin Erlang
any CUI
process
stdout

21. Linked-in Driver
in-process erlang-port,
% acts like an Erlang process
% Message can be sent/recv’d,
less failure-separeted.
Erlang
process
output(..){
?DEMO. ... }

22. Native Interface
Functions
Since R13B03, Beta,
Built-in code runs inside ERTS,
almost hacking ERTS, Erlang
process
Nothing separated.
hello(..){
... }

23. NIF fast
tightly
ideal
coupled
Linked-in Driver
standard
specialized Port Driver
loosely
useless
coupled
C node
slow

24. Examples:
Erlang TC drivers

25. tcerl
Pioneer in TC-Erlang!
Port driver,
“I couldn’t make it work”, - matthew,
seems not being maintained.

26. Toke
Most famous in TC-Erlang,
Linked-in driver,
Simple: just what matthew/LShift wants,
to be used in RabbitMQ?.

27. Yatce
Made in Japan by me,
Linked-in driver (0.10) / NIF (0.20),
interface based on tokyocabinet.idl,
maybe fastest...(see graphs)

28. Yatce 0.20 fast
tightly
ideal
coupled
Toke
standard
specialized tcerl
loosely
useless
coupled??
slow

29. Comparison

30. less-related
Conclusion
all these technologies
are based on
Erlang Binary format.
It’s great.

31. Any Questions?
or
come on to the party
and ask me!

32. References
ERTS: Interoperability tutorial guide
http://www.erlang.org/doc/tutorial/overview.html
BERT/BERT-RPC
http://github.com/blog/531-introducing-bert-and-bert-rpc
http://bert-rpc.org/
Erlang external term format
http://erlang.org/doc/apps/erts/erl_ext_dist.html
NIF
http://erlang.org/doc/man/erl_nif.html
Toke, vs tcerl
http://bit.ly/8nPhm2
Erlang external term format