Accelerating Application Performance with Amazon ElastiCache (DAT207) | AWS re:Invent 2013

1. DAT207 - Accelerating Application Performance with Amazon ElastiCache Omer Zaki (AWS) / Nick Dor (GREE) / James Kenigsberg (2U) November 14, 2013 © 2013 Amazon.com, Inc. and its affiliates. All rights reserved. May not be copied, modified, or distributed in whole or in part without the express consent of Amazon.com, Inc.

2. Speakers • Omer Zaki – Senior Product Manager, AWS – omerz@amazon.com • Nick Dor – Senior Director of Engineering, GREE International, Inc. • James Kenigsberg – Chief Technology Officer, 2U, Inc.

3. What is a Cache? • Specialized data store that keeps frequently accessed data in memory • Memory is order of magnitudes faster than disk

4. Why Use a Cache? • “Latency is the mother of interactivity”* • Handle hot data, handle spikes • Reduce load on backend • For a majority of web applications, workloads are read heavy – Often as high as 80-90% reads vs. writes * http://highscalability.com/blog/2009/7/25/latency-is-everywhere-and-it-costs-you-sales-how-to-crush-it.html

5. Caches, caches, caches • Types – browser cache, proxy cache, server cache, database cache, file system cache • Characteristics – persistence, scalability, data model, warming • Architecture – side cache, read through, write back • Options – Memcached, Redis, etc.

6. Memcached • Free, open-source, high-performance, in-memory key-value store • Developed for LiveJournal in 2003 • Used by many of the worlds top websites – YouTube, Facebook, Twitter, Pinterest, Tumblr, …

7. Memcached: Architecture value = get(key) API APP database reads / writes Client Lib set(key,value,expiry) add(key,value,expiry) replace(key,value,expiry) app reads / cache updates persistent TCP session no communication between servers which memcached server? server = server_list [key mod n] can handle large number of TCP sessions Source: http://architects.dzone.com/news/notes-memcached

8. Redis • High speed, in-memory, key-value data store • Data structure support – strings, lists, sets, sorted sets • Asynchronous replication • Optional durability (persistence via snapshot or append-only file) • Pub/sub functionality

9. Redis: Architecture Redis Read Replica Redis Master App Reads Cache Updates Clients App MySQL DB Instance

10. Amazon ElastiCache • Web service that lets you easily create and use cache clusters in the cloud • Memcached, Redis compatible • Managed, scalable, secure • Pay-as-you-go and flexible, so you can add capacity when you need it

11. Amazon ElastiCache Architecture

12. Where is Amazon ElastiCache used? • • • • • • • Gaming Social Media & Entertainment Mobile E-Commerce Ad Tech Many more…

13. Sample Deployment: Gaming • Auto Scaling front end • Amazon ElastiCache • Amazon RDS • Amazon S3 • Amazon CloudFront ZADD ZADD ZADD ZADD leaderboard leaderboard leaderboard leaderboard 556 819 105 1312 “Andy” “Barry” “Carl” “Derek” ZREVRANGE leaderboard 0 -1 1) “Derek” 2) “Barry” 3) “Andy” 4) “Carl”

14. Design Patterns • Low latency / high throughput store • Database offloading • Session management • In-memory storage for difficult or timeconsuming tasks • • • • • Leaderboards High-speed sorting Atomic counters Queuing systems Activity streams

15. Amazon ElastiCache at GREE Nick Dor – Sr. Director, Engineering GREE International, Inc. November 14, 2013 © 2013 Amazon.com, Inc. and its affiliates. All rights reserved. May not be copied, modified, or distributed in whole or in part without the express consent of Amazon.com, Inc.

16. GREE International • 2004 – GREE is founded in Japan • 2011 – establishes office in US – Hosting games in traditional datacenters – 2 weeks to procure and provision new servers + 1 week to setup application – ITIL practices (Dev / Ops separation) • 2012 – acquires Funzio – AWS hosted – Quick provisioning of servers (minutes) / but still manual setup (days) – Hybrid hosting environment • 2013 – consolidates in AWS – Migrated games from traditional datacenter to AWS – Automated application setup – DevOps practices (c) GREE

17. GREE Games • All Mobile, all Free-to-Play – iOS & Android smart phones – Big focus on tablets • Role Playing Games (RPG+) – Multi-million dollar franchise, top-grossing titles – Some of the oldest games on the App Store • Hardcore – Deeper more intense gameplay mechanics • Real-Time Strategy (RTS) – Fast action, small unit management • Casino & Casual Games – Familiar games, wider audience, casual play (c) GREE

18. Some Scale • Over 60 ELB endpoints hosted in AWS – Games, shared services, analytics infrastructure • • • • • 1200 Amazon EC2 instances 400 Amazon ElastiCache nodes 260 Amazon RDS database servers 1TB daily logs from app servers Millions of monthly active users (c) GREE

19. Example Game Architecture – RPG+ • Application Servers Elastic Load Balancing – PHP – Game events  Analytics App App App App Cache Cache Cache Cache Batch Batch RDS RDS • Cache Layer – Memcached  ElastiCache • Batch Processing Servers – Node.js (moving to GO) – Batches database writes • Database Failover DB – MySQL  RDS (c) GREE RDS

20. Caching Strategy • Game architecture predates stable NoSQL – We wanted similar performance at scale – Keep combined average internal response times below 500ms • Memcache Authoritative – Still use an RDBMS; potential data loss is limited • Allows for cheaper/simpler DB layer – Always do full row replacements (ie: no current_row_value +1) (c) GREE

21. Elastic Load Balancing Data Flow App App App Cache • Reads App Cache Cache Cache Batch Batch RDS RDS – ELB  App  Cache • Writes (Synchronous) – – – – ELB  App  Cache  DB ELB  App  Cache  Batch  DB Standard write-through No blind writes; always fetch current ver. • Writes (Asynchronous) – Batch  DB – Batch writes to DB every 30 seconds (c) GREE RDS

22. Batch Processor • 80% of game write traffic is asynchronous • Ex: Player items (loot) after multiple quests – 10 items in 30 sec; app server sends 10 writes downstream – Batch processor sends last record with final item count to DB • Greatly reduced writes on DB – Shard at table and DB server level for larger games (c) GREE

23. Memcache Writes - Key Facts • App handles memcache key hashing & sharding – DB rows are usually just a key, version, timestamp & JSON blob – Look familiar? • NEVER do blind writes – Always fetch current value in MC, perform operation, then write • If version collision, then simply fail – Extremely rare; application will retry for some calls (c) GREE

24. Memcache Writes – High Concurrency • Player vs. Player Events (World Domination) – These have much higher concurrency – Match-making, battles/results, leaderboards • Here we do relative updates at MC layer – Yes, we contradict ourselves here a little • If we get a version collision/failure – App server reloads MC value and tries again, up to 5 times – Usually on 2nd or 3rd try we succeed – This happens VERY fast in the code (c) GREE

25. Failure Scenarios • Memcache node fails – Go straight to the database; versioning is key here • Hashing compartmentalizes impact – During failure, only players assigned to that node are affected – Usually only a small performance drop • Node comes back online… – Cache is refilled organically – DB load for that subset of operations decreases over time (c) GREE

26. Why Amazon ElastiCache? • Fairly stable – Fails less regularly than Amazon EC2 • Automatic node replacement – Same node name/DNS • Good performance – Highest performance with larger instances (network layer) • Configuration endpoint – Application can dynamically add/remove nodes – Automatically rebalance hashes to accommodate new nodes – No more manual memcache migrations – YAY! (c) GREE

27. Newer Games - Architecture • MUCH more modern in terms of arch/tech • Shift towards real-time games – Longer play sessions; higher player engagement – Will impact our caching model – less pools, but larger • Streaming, queuing – GO, nsqd • Moving (finally) to memcached – Had used old memcache libraries for long time (c) GREE

28. Future Trends in Caching at GREE • Check and Set tokens (CAS) – A sort of internal versioning in memcached – Ensures data is latest before updating – Atomic transactions • Investigate real NoSQL implementation • Redis - Promising – Need to see how I/O performance goes when hitting disk (c) GREE

29. How 2U is Building the World’s Premier Online Learning Programs James Kenigsberg, CTO, 2U, Inc. November 14, 2014 © 2013 Amazon.com, Inc. and its affiliates. All rights reserved. May not be copied, modified, or distributed in whole or in part without the express consent of Amazon.com, Inc.

30. 2U partners with top universities to deliver the world’s best online programs - Real degrees - Real live classes - Real faculty - Real outcomes

31. Graduate Undergraduate

32. Prospect Mgmt App Process Security University Partner Learning and Management Stack Our best-in-class, proprietary technology platform can be Online Campus CRM Content Mgmt integrated across numerous university clients, program verticals, and individual classes

33. 2U Online Campus Far more than what you think of as a Learning Management System... ...the 2U Online Campus represents the single hub for students’ asynchronous study, live class sessions, and dynamic social tools to create a rich, online student community.

34. “No man ever steps in the same river twice, for it’s not the same river and he’s not the same man.” - Heraclitus

35. 2008 Servers Engineers Developer

36. 2009 Servers Engineers

37. 2009 • Surly French Canadians • Configuring our own load balancers • No MySQL clustering • Save us! SOS…

38. Set Amazon’s servers on fire, not ours

39. 2010 • Amazon to the rescue! • Release of Amazon RDS for databases • Release of Elastic Load Balancing for load balancing • Caching helps students communicate! • • Memcache No file redundancy

40. 2011 Instances 100 Engineers 2

41. 2011 • Redundancy! • • • GlusterFS More Availability Zones Using new AWS services as fast as they release them • Amazon S3 – Backups • Amazon SES – Outbound email • Amazon Route 53 – A lifesaver! (Zerigo outage)

43. 2012 • Stack growth • API layer • Amazon ElastiCache • DevOps! • Puppet • Jenkins • AWS CloudFormation

45. 2013 • Amazon S3 to the rescue • More AWS! • Amazon Redshift data warehouse

46. Amazon is committed to customers

47. We are committed to changing your life

48. Impact: Education 1,704 3,287,000 Graduates K–12 Students 1,097 2,116,000 Current Students K–12 Students Through 2019 12,496,000 K–12 Students

49. Please give us your feedback on this presentation DAT207 As a thank you, we will select prize winners daily for completed surveys! Want more caching: Attend Amazon ElastiCache Architecture and Design Patterns Friday @ 11:30am – 12:30pm Lido 3006