This document provides an overview and agenda for a presentation on Amazon ElastiCache. The presentation will discuss why in-memory data stores are important for modern applications that require real-time performance. It will then introduce Amazon ElastiCache as a fully managed in-memory cache in the cloud, supporting the Redis and Memcached protocols. Finally, it will cover several common use cases for ElastiCache including caching, leaderboards, chat/messaging, ratings, and rate limiting.

1. Amazon ElastiCache
AWSIn-Memory DataStore
Dan Zamansky
Senior Product Manager
Time : 11:30 – 12:00

2. Amazon ElastiCache
AGENDA
• Why In-Memory?
• ElastiCache
• Understanding Key Features
• Redis - Common Use Cases

3. Why In-Memory?

4. Modern Applications Require Real-Time Performance
• We live in a connected world (IoT)
• Phones, Tablets, Cars, Air Conditioners, Toasters
• Experiences are increasingly contextual
• Apps need to provide real-time responses
• Database performance is frequently the bottleneck
• Load is spikey and unpredictable

5. Businesses Need To Be Ready For Success!

6. What is ElastiCache?

7. Amazon RDS
Amazon DynamoDB Amazon Redshift
Amazon
ElastiCache
Compute Storage
AWS Global Infrastructure
Database
Application Services
Deployment & Administration
Networking
AWS Database Services
High Performance In-Memory Key-
Value Store in the Cloud

8. In-Memory Key-Value Store
High-performance
Redis and Memcached
Fully managed; Zero admin
Hardened by Amazon
Amazon
ElastiCache

9. Fully managed service = Automated Operations
Redis/Memcached Datastore hosted on Amazon EC2 Amazon ElastiCache

10. Amazon
RDS
Request Rate
High Low
Cost/GB
High Low
Latency
Low High
Data Volume
Low High
Amazon
Glacier
Amazon
CloudSearch
Structure
Low
High
Amazon
DynamoDB
Amazon
ElastiCache

11. Memcached
Slab allocator
In-memory key-value datastore
very popular as a caching solution
Supports strings, objects
Multi-threaded
Insanely fast!
Very established
No persistence
Patterns for sharding

12. Redis – the in-memory king
Powerful
~200 commands
In-memory key-value datastore
Supports data types
strings, lists, hashes, sets, sorted sets,
bitmaps & HyperLogLogs
Single-threaded
Atomic operations
supports transactions
has ACID properties
Ridiculously fast!
<1ms latency for most commands
Read replicas
Persistence
snapshots or append-only log
Pub/sub functionality

13. Amazon
ElastiCache
Redis Multi-AZ
Easy Monitoring via CloudWatch
Fully Managed
Enhanced Redis Engine
Easy to Deploy & Use
ElastiCache vs. Self-Managed Redis
No Cross-AZ Data Transfer Costs
Engineered For Cloud Scale

14. Amazon
ElastiCache
Enhanced Redis Engine – Hardened by Amazon
RDB Without Fork
• Mitigate the risk of increased swap
usage during syncs and snapshots.
Dynamic write throttling
• To improve output buffer
management when the node’s
memory is close to being exhausted
Smoother failovers
• Clusters recover faster as replicas will
avoid flushing their data to do a full
re-sync with the primary.

15. Mitigating Swap During Redis Fork

16. Primary
Availability Zone A Availability Zone B
Replica
Replica
writes
Use Primary Endpoint
reads
Use Read Replicas
Auto-Failover
 Chooses replica with
lowest replication lag
 DNS endpoint is same
ElastiCache for Redis Multi-AZ
ElastiCache
for Redis
ElastiCache
for Redis
ElastiCache
for Redis
Automatic Failover to a read replica in case of primary node failure
ElastiCache
Automates
snapshots for
persistence

17. ElastiCache with Redis Multi-AZ
Region
Availability Zone A Availability Zone B
Auto Scaling group
ElastiCache cluster

18. ElastiCache with Redis Multi-AZ
Region
Availability Zone A Availability Zone B
Auto Scaling group
ElastiCache cluster

19. ElastiCache with Redis Multi-AZ
Region
Availability Zone A Availability Zone B
Auto Scaling group
ElastiCache cluster

20. ElastiCache with Redis Multi-AZ
Region
Availability Zone A Availability Zone B
Auto Scaling group
ElastiCache cluster

21. Mitigating Replica Flushing – Enhanced Engine
Master Replicas

23. Alarms
Monitoring with CloudWatch
• Easily Accessible via the
ElastiCache console
• Track health of your
nodes
• Set alarms to act when
need to address running
into limitations

24. What apps can ElastiCache power?

25. We Run The Most Demanding Real-Time Workloads
Thousands of Customers Implementing Large Scale Caching, Leaderboards,
Session Management, Messaging, Queuing and more
Gaming AdTech Media Mobile Other

26. Let’s Talk Redis. Key Use Cases

27. Use Case #1 - Caching
Elastic Load
Balancing
EC2 App
Instances
RDS MySQL
DB Instance
ElastiCache
Database Writes
App
Reads
Clients
Cache
Updates
Database Reads

28. Amazon
ElastiCache
Eliminate database hotspots
Predictable Performance
Cut Load on Backend
Increase Read Throughput
Reduce App Latency
Caching Will Make Your Database More Efficient
Reduce Database Cost

29. Adding Caching to Your Application is Easy
Common Caching Technique #1 – Lazy Caching:

30. IGA Works Uses ElastiCache to Power Real-Time App Monetization
By using RDS we saved on operations
cost for our relational databases. Using
ElastiCache we could boost the read
performance of RDS and offload the
massive request rate
Jeongsang Baek
VP Engineering, IGA Works
”
“
• IGA Works is Korea’s leading mobile business platform
• Adpopcorn is an ad monetization platform for mobile applications
that supports 130 million devices
• Storing Ad Inventory in ElastiCache in front of RDS guaranteed real-
time ad bidding and serving, while RDS provides the durable
database layer

31. Expedia’s Real-time Analytics Application Uses Amazon ElastiCache
Expedia is a leader in the $1 trillion travel industry, with an extensive portfolio that
includes some of the world’s most trusted travel brands.
With ElastiCache Redis as caching
layer, the write throughput on
DynamoDB has been set to 3500,
down from 35000, reducing the cost
by 6x.
Kuldeep Chowhan
Engineering Manager, Expedia
”
“ • Expedia’s real-time analytics application collects data for its “test &
learn” experiments on Expedia sites.
• The analytics application processes ~200 million messages daily.
• Re:invent talk: https://www.youtube.com/watch?v=ie4dWGT76LM

32. Not if I
destroy
it first!
It’s
mine!
• Very popular for gaming apps
• Need uniqueness + ordering
• Easy with Redis Sorted Sets
ZADD "leaderboard" 1201 "Gollum”
ZADD "leaderboard" 963 "Sauron"
ZADD "leaderboard" 1092 "Bilbo"
ZADD "leaderboard" 1383 "Frodo”
ZREVRANGE "leaderboard" 0 -1
1) "Frodo"
2) "Gollum"
3) "Bilbo"
4) "Sauron”
ZREVRANK "leaderboard" "Sauron"
(integer) 3
Use Case 2 - Real-time Leaderboard

33. TV Globo (Media)
• Rede Globo is the second largest TV network in the
world.
• TV Globo used ElastiCache Redis for second screen
application during the World Cup in Brazil in 2014.
• ElastiCache was used for caching and leaderboards.
• Massive spikes in usage during games and peak
events.

34. Use Case 3 - Chat and Messaging
• PUBLISH and SUBSCRIBE Redis commands
• Game or Mobile chat, real-time comment streams
• Server intercommunication
SUBSCRIBE chat_channel:114
PUBLISH chat_channel:114 "Hello all"
>> ["message", "chat_channel:114", "Hello all"]
UNSUBSCRIBE chat_channel:114

35. • Popular for recommendation engines and message board ranking
• Redis counters – increment likes/dislikes
• Redis hashes – list of everyone’s ratings
• Process with algorithm like Slope One or Jaccardian similarity
• Ruby example - https://github.com/davidcelis/recommendable
Use Case 4 – Ratings
INCR item:38927:likes
HSET item:38927:ratings "Susan" 1
INCR item:38927:dislikes
HSET item:38927:ratings "Tommy" -1

36. • Ex: Throttling requests to an API
• Leverages Redis Counters
ELB
Externally
Facing A
PI
Reference: http://redis.io/commands/INCR
FUNCTION LIMIT_API_CALL(APIaccesskey)
limit = HGET(APIaccesskey, “limit”)
time = CURRENT_UNIX_TIME()
keyname = APIaccesskey + ":” + time
count = GET(keyname)
IF current != NULL && count > limit THEN
ERROR ”API request limit exceeded"
ELSE
MULTI
INCR(keyname)
EXPIRE(keyname,10)
EXEC
PERFORM_API_CALL()
END
Use Case 5 - Rate Limiting

37. • Redis is a powerful in-memory data structure server that
allows you to easily build high performance apps
• ElastiCache provides the hardened, secure, highly-available,
and performant platform to run in-memory data stores
in the cloud
Recap

38. Thank You