2016/09/27 Cache Night http://gunosy-beer.connpass.com/event/40945/ で発表した、 Goとmemcachedとマイクロサービスの話です。キャッシュ戦略やライブラリ選定、紹介の話がメインです。

1. Go, memcached,
microservices
2016/09/27 cache_night
@mosa_siru

2. @mosa_siru ( )
•
• 2

3. @mosa_siru as engineer
• DeNA
• Gunosy
• CTO

4. 1.
2. cache
3. cache
4. microservices

5. Cache is hard

6. • Cache Invalidation
• There are only two hard things in Computer Science: cache
invalidation and naming things. -- Phil Karlton
•
• TTL
•
• thundering herd

7. •
•
• DB

8. Cache Invalidation

9. Cache Invalidation
• (DB)

10. Cache Invalidation
• DB
memcached
• ( API
memcached ) TTL

11. Cache Invalidation
• Invalidation
•
•
ID

12. thundering herd

13. Thundering Herd
• expire
(DB)
• DB
•

15. • 2016/06 KDDI
•
•

16. •
•
•
•
•
•

17. •
• Push
•
•

18. • 2
get

19. (1)
1. local memd 2.

20. (2)
1. local memd
2.
remote
4. local set
3.

21. (3)
1. local memd
2.
remote
6. local set
4.
3. DB
5. remote set

22. • TTL (5s-60s)
TTL (60s-1h) invalidation
updatedelete

23. • local memd
• DB thundering herd
• local memd TTL invalidation
local memd

24. •
insert invalidation
insertdelete

26. • memcached
• redis
• go process cache
• go groupcache
• File DB

27. Redis
•
•
•
•

28. Go process cache
•
•
• local, remote
• remote

29. Go groupcache
• google memd
local/remote
•
• expire …

30. File DB
•
File DB(LevelDB )
•
•
•

31. memcached
•
•
• AWS Elasticache
• JSON msgpack

32. go memcached client

33. go memcached client
•
1. bradfitz/gomemcache
2. douban/golibmc

34. 1. gomemcache Pros
• (600star)
• go

35. 1. gomemcache Cons
• 1 issue, PR
• memcached
• SetMulti,
DeleteMulti

36. 1. gomemcache Cons
• TCP 2
(2 )
• 2 configurable PR
•
memcached
•

37. 2. golibmc Pros
• C
• SetMulti
• ”noreply"
(TCP 1 )
• issue PR 2

38. 2. golibmc Cons
• Python libmc (320start)
golibmc
• C

39. 2. golibmc Cons
• goroutine 1Client 1
•
• Client
gomemcache

40. • golibmc
•
• issue PR 2
• SetMulti
•
•

41. go

42. 1. local memd
2.
remote
6. local set
4.
3. DB
5. remote set

43. 1
get multi
get multi
select …
where id in
…
set multi
set multi
ID( )
get, set 1

44. • https://github.com/mosasiru/memd
•
• GetOrSet
• GetOrSetMulti

45. GetOrSet
• local/remote memd

46. GetOrSetMulti
• local/remote memd
GetMulti/SetMulti

47. mosasiru/memd
•
ver0.1 … patch is welcome!!!!

48. microservices

50. microservices
•
• API
• DB
• AWS security group/IAM
•

51. microservices
• API
• API

52. microservices
• cache
• invalidation

53. invalidation
• (DB) write read
• cache invalidation
write read

54. invalidation
• cache read/write 1
• cache key 1
• consistent hash 1
write
DELETE /hoge/cache
delete
Worker API
…

55. CDN
• CDN
• URL invalidation
https://...?t=1474969378

57. Cache is hard…

58. Gunosy
@mosa_siru