LUMS 2010 final year computer science senior project presentation

1. Building a Scalable
Social Networking Engine
Like the big boys

2. Déjà vu?

3. Sender
Server
Processor
Database
Message
Receivers
Sender
Group SMS

4. Current architecture
Why it failed?
Even Twitter did!

5. Sender Message
Polling

6. Sender Message
Polling
Server
Processor
Database

7. Sender
Server
Processor
Database
Message
Polling

8. Sender
Server
Processor
Database
Message
Polling

9. Sender
Server
Processor
Database
Message
Polling
Receivers
Sender

10. Sender
Server
Processor
Database
Message
Receivers
Sender
Polling

11. Sender
Server
Processor
Database
Message
Receivers
Sender
Polling

12. • Database Size = x
• Average Time = xxxs
• Average Lookups = x
• Average Number of Rows Traversed = x
Polling

13. • Database Size = 3x
• Average Time = 3xxxs
• Average Lookups = 3x
• Average Number of Rows Traversed = 3x
Polling

14. • Database Size = 9x
• Average Time = 9xxxs
• Average Lookups = 9x
• Average Number of Rows Traversed = 9x
Polling

15. • FAIL!
Polling

16. • Stores the text of a SELECT statement
together with the corresponding result
SQL Query Caching

17. • Stores the text of a SELECT statement
together with the corresponding result
• Faster access time – identical queries are
only processed once
SQL Query Caching

18. • Stores the text of a SELECT statement
together with the corresponding result
• Faster access time – identical queries are
only processed once
• Works for reading intensive apps
• MySQL's query cache destroys the entire
cache for a given table whenever that table
is changed (every 5-10 seconds)
SQL Query Caching

19. • FAIL!
SQL Query Caching

20. • All (or some) of the tables are opened and
put in memory
SQL Table Caching

21. • All (or some) of the tables are opened and
put in memory
• Faster access time – memory is faster than
backing storage
SQL Table Caching

22. • All (or some) of the tables are opened and
put in memory
• Faster access time – memory is faster than
backing storage
• Not an Object Cache – message response
construction involves multiple table
lookups. SQL can’t cache those lookups as a
group (object). RDBMS paradigm.
SQL Table Caching

23. • FAIL!
SQL Table Caching

24. THE NEW
Why it will be super fast…
…and pretty!

25. High-performance, distributed memory,
write-through, non-blocking object
caching system
Memcached
(mem-cash-dee)

26. High-performance, distributed memory,
write-through, non-blocking object
caching system
Memcached
(mem-cash-dee)
The only thing cooler than that is ice.

27. Architecture
Interface
Business Layer
API
Cache Database

28. Single-thread
Was.

29. Multi-threading
Is.

30. Please