1. Cell Architecture
For Large Scale Service
charsyam@naver.com

2. Agenda
•Basic Architecture
•Query-Off Style Architecture
•Cell Architecture

3. Basic Architecture
CLIENT WEB DB
Read/Write

4. Basic Architecture
Overhead

5. Overhead
What
causes
Overhead

6. Overhead
Profiling

7. Profiling
JavaScript
CSS
CLIENT

8. Profiling
JavaScript
CSS
CLIENT
Optimization

9. Profiling
Business LogicWEB

10. Profiling
Business LogicWEB
Optimization
Increase WEB/AS

11. Second Architecture
CLIENT WEB DB
Read/Write
WEB
WEB

12. Second Architecture
Easy!!!

13. Profiling
Storage LayerDB

14. Profiling
Storage LayerDB
I/O Consists of
Read/Write

15. Profiling
Generally
READs are more
than WRITEs

16. Profiling
Distribute READs

17. Profiling
200 writes/s
800 reads/s
Read > Write

18. Simple DB Architecture
Master
Slave
REPLICATION/FailOver

19. Query-Off Architecture
WEB/AS
Master
Slave
ONLY WRITE
Slave Slave
Only READ
REPLICATION

20. Query-Off Architecture
200
writes/s
800
reads/s
200
writes/s
400
reads/s
200
writes/s
400
reads/s
Read/1 Server Read/2 Server

21. Query-Off Architecture
Is performance
proportional to
numbers of Slaves?

22. Query-Off Architecture
700
writes/s
50
reads/s
700
writes/s
50
reads/s
700
writes/s
50
reads/s
700
writes/s
50
reads/s
700
writes/s
50
reads/s
Write Heavy Situation

23. Query-Off Architecture
Zero-Sum Game

24. Profiling
Distribute Writes

25. How?

26. Clustering
and
Sharding

27. Clustering
seems to be
Ideal

28. Clustering – Large one
Web
Web
Web
DB
DB DB
DB

29. Clustering
Difficult

30. Sharding

31. Sharding
WEB/AS
Master Master Master
User A Data
User C Data
User D Data
User B Data
User X Data
User Z Data
User Y Data
User E Data
User F Data

32. Cell Architecture
Cell 0 Cell 1 Cell 2
User
Cell Info
Server
ID: CharSyam
CellID: 1, Status: Normal
Get/set

33. Cell Architecture
A Cell is Full-Set
Can serve Users

34. Cell Examples #1
WEB/AS
Master Slave
WEB/AS WEB/AS

35. Cell Examples #2
WEB/AS WEB/AS WEB/AS
Master
Slave Slave Slave
READ only
WRITE only

36. Failure of Cell Architecture
Cell 0 Cell 1 Cell 2
User
Cell Info
Server
ID: CharSyam
CellID: 1, Status: Normal
Can’t Service

37. Failure of Cell Architecture
Cell 0 Cell 1 Cell 2
User
Cell Info
Server
ID: CharSyam
Can’t response
Get/set

38. • Benefits
–Easy to extend
–Failure is limited to some Users in same cell.
–Can deploy specific feature to some cell users.
• Liabilities
–To need more servers.
• To build full-set
Cell Architecture

39. Q&A

40. Thank you