This document discusses node.js and its use of server-side JavaScript. It begins by explaining that node.js uses an event-driven, non-blocking I/O model to handle multiple connections simultaneously in a single-threaded process. It then covers some of the motivations for this approach, including how it helps address latency issues and improves performance compared to traditional blocking I/O. The document also provides some history around node.js and its use of the CommonJS module system.

1. W ha tis
SpringSproutSwagger
2011.01.29
Outsider

5. node.jsis
Server-side
JavaScript

6. “노드가아직은서버사이드
자바스크립트의개념을취한
많은것들중하나로보이지만
”
그것들보다훨씬흥미롭다.
SimonWillison
http://simonwillison.net/2009/Nov/23/node/

7. Motivation

8. I/O는다르게
수행되어야한다.

9. varresult=db.query('select*fromA')
//useresult

10. varresult=db.query('select*fromA')
//useresult
왜기다려야하는가?

11. I/Olatency
L1 1ns
L2 4.7ns
RAM 83ns
DISK 13,700,000ns
Internet 80,000,000ns
http://duartes.org/gustavo/blog/post/what-your-computer-does-while-you-wait

12. 싱글쓰레드를이용한
EventLoop가
더낫다

13. db.query('select*fromA',
function(result){
//useresult
}
);

14. 동시접속수에따른초당리퀘스트처리수
초당리퀘스트
12,000
nginx
9,000
6,000
apache
3,000
0
0 500 1000 1500 2000 2500 3000 3500 4000
동시접속수
http://blog.webfaction.com/a-little-holiday-present

15. 동시접속수에따른메모리사용량
MB
40
apache
30
20
10
nginx
0
0 500 1000 1500 2000 2500 3000 3500 4000
동시접속수
http://blog.webfaction.com/a-little-holiday-present

16. 왜모두EventLoop를
사용하지않는가?

18. 문화적인이유

19. 우리가
I/O를
그렇게
배웠다

20. puts('이름을입력하세요:');
varneme=gets();
puts('이름:'+name);

21. puts('이름을입력하세요:');
gets(function(name){
puts('이름:'+name);
});
어렵다어려워

22. 인프라적인이유

23. SingleThreadEventLoop는
non-blockingI/O가필요하다.

24. 대부분의라이브러리가
non-blockingI/O를
지원하지않았다

25. 현재는많은인프라가
갖추어져있다.
예:Twisted,eventmachine

26. 블락킹I/O와
넌블락킹I/O를
섞어서
사용하는것이
어렵다

27. EventLoop와non-blockingI/O에대한
전문지식이필요하다

28. JavaScript

29. 유니버셜랭귀지

30. EventLoop를
사용하도록
디자인되었다

31. 성능을위한
경쟁이붙었다

32. 이제다시....

33. RyanDahl
09.02.09
V8에기반한프로젝트
아이디어에대한글을올림
09.02.15
Github에프로젝트시작
09.11.08
JSConf.eu2009발표
(v0.1.16)
11.01
현재-v0.2.6,0.3.7

34. CommonJS기반

35. JavaScript는더이상
브라우저를위한것이아니다.
CommonJS기반

36. KevinDangoor가만든
웹브라우저이외의환경에서
JavaScript를사용하기위한스펙
Modules,System,Filesystem,UnitTesting
CommonJS기반

37. node.js
CouchDB
RingoJS
SproutCore
CommonJS기반

38. 에서 동작
V 8위

39. C/C++애드온

40. 직접짠코드외에는
모두비동기

41. 모두
non-blockingI/O

42. 단하나의쓰레드
단하나의스택

43. index.html페이지요청
node
execution
stack
ev_loop()

44. index.html페이지요청
socket_readable(1)
node
execution
stack
ev_loop()

45. index.html페이지요청
http_parse(1)
socket_readable(1)
node
execution
stack
ev_loop()

46. index.html페이지요청
load(“index.html”)
http_parse(1)
socket_readable(1)
node
execution
stack
ev_loop()

47. index.html페이지요청
http_parse(1)
socket_readable(1)
node
execution
stack
ev_loop()

48. index.html페이지요청
socket_readable(1)
node
execution
stack
ev_loop()

49. index.html페이지요청
node
execution
stack
ev_loop()

50. 메모리에대한두번째요청
node
execution
stack
ev_loop()

51. 메모리에대한두번째요청
socket_readable(2)
node
execution
stack
ev_loop()

52. 메모리에대한두번째요청
http_parse(2)
socket_readable(2)
node
execution
stack
ev_loop()

53. 메모리에대한두번째요청
http_respond(2)
http_parse(2)
socket_readable(2)
node
execution
stack
ev_loop()

54. 메모리에대한두번째요청
http_parse(2)
socket_readable(2)
node
execution
stack
ev_loop()

55. 메모리에대한두번째요청
socket_readable(2)
node
execution
stack
ev_loop()

56. 메모리에대한두번째요청
node
execution
stack
ev_loop()

57. index.html요청에대한응답
node
execution
stack
ev_loop()

58. index.html요청에대한응답
file_loaded()
node
execution
stack
ev_loop()

59. index.html요청에대한응답
http_respond(1)
file_loaded()
node
execution
stack
ev_loop()

60. index.html요청에대한응답
file_loaded()
node
execution
stack
ev_loop()

61. index.html요청에대한응답
node
execution
stack
ev_loop()

62. 은가 ?
엇이 좋
무

63. 이좋 고 빠르다
성능

64. RealtimeApp에좋다

65. 100동시접속에1MB응답
node822req/sec
nginx708req/sec
thin85req/sec
mongrel4req/sec
(클수록좋다)
http://chetansurpur.com/blog/2010/10/why-node-js-is-totally-awesome.html

66. 다른기술과
함께쓸수있다

67. 가쉽 다
작 하 기
시

68. “
node.js는
내가똑똑한것처럼
”
느끼게만들어준다
TobieLagel
http://twitter.com/#!/tobie/status/8975802142031872

69. 단점은?

70. 아직어리다

71. 멀티CPU/데이터센터간의
확장성문제

72. 간단한예제들
fromryan
node.jsv0.2.6

73. //helloworld.js
varsys=require('sys')
setTimeout(function(){
sys.puts('world');
},2000);
sys.puts('hello');

74. //forever_helloworld.js
varputs=require('sys').puts;
setInterval(function(){
puts('hello');
},500);
process.on('SIGINT',function(){
puts('good-bye');
process.exit(0);
});

75. //tcp.js
vartcp=require('net');
varserver=tcp.createServer();
server.on('connection',function(e){
e.write('hello!n');
e.end();
});
server.listen(8000);

76. //fileio.js
varstat=require('fs').stat,
puts=require('sys').puts;
stat('/etc/passwd',
function(err,data){
if(err)throwerr;
puts('modified:'+data.mtime);
}
);

77. //streamhttp.js
varhttp=require('http');
http.createServer(function(req,res){
res.writeHead(200,
{'Content-Type':'text/html'});
res.write('Hellon');
setTimeout(function(){
res.write('world!n');
res.end();
},2000);
}).listen(8000);

78. //watchfile.js
varfs=require('fs'),
puts=require('sys').puts;
fs.watchFile('./test.txt',
function(){
puts('파일을바꾸셨군요.');
process.exit(0);
});

79. node.js는서비스할
준비가되었는가?

80. “node.js는
무시하기에는
너무쿨하다
DustinMcQuay
”
http://www.synchrosinteractive.com/blog/9-nodejs/22-nodejs-has-a-bright-future

81. Questions...?
Blog:http://blog.outsider.ne.kr
Twitter:@outsider__
email:outsideris@gmail.com

82. 사진출처(underCCL)
http://www.flickr.com/photos/41534655@N00/220318384/
http://www.flickr.com/photos/blank22763/4089949526/
http://www.flickr.com/photos/arthurjohnpicton/4383221264/
http://www.flickr.com/photos/75898532@N00/3110092806/
http://www.flickr.com/photos/f-l-e-x/3092386087/
http://www.flickr.com/photos/chefranden/4596604619/
http://www.flickr.com/photos/tjook/5111553020/
http://www.flickr.com/photos/franksvalli/5163205409/
http://www.flickr.com/photos/rawryder/5086090931/
http://www.flickr.com/photos/elvinj/4487097018/
http://www.flickr.com/photos/ramdac/373881476/
http://www.flickr.com/photos/gregw/3592153959/