12 - ElastiCache

Question 1

ElastiCache

Answer 1

ElastiCache

• Typically given a scenario where a database is a user a lot of stress/load. Which service would you use to alleviate this?
  
  • Elasticache is a good choice if your database is particularly read-heavy and not prone to frequent changing
  • Redshift is a good choice if your database is feeling stress because management keeps running OLAP (Online Analytic Transactions) transaction on it

Question 2

ElastiCache - In-Memory Caching Engines

Answer 2

ElastiCache

• It has two open-source in-memory caching engines
  
  • Redis
    
    • Open source in-memory key-value store that supports data structures such as sorted sets and lists
    • ElastiCache supports Master / Slave replication and multi-AZ redundancy
  • Memcached
    
    • Object caching system
    • Elasticache is protocol compliant with Memcached

Question 3

Memcached Use Cases

Answer 3

Memcached Use Cases

• Object caching is the primary goal
• Keep things as simple as possible
• Is designed as a pure caching solution with no persistence
• You want to scale your cache horizontally (scale-out)

Question 4

Redis Use Cases

Answer 4

Redis Use Cases

• Use for advanced data types, such as lists, hashes, and sets (e.g. leaderboards)
• Used for sorting/ranking data sets in memory
• Need data persistence
• Need to run in multiple AZs with failover
• Pub / Sub capabilities are needed

Question 5

Typical Use Case

Answer 5

Typically given a scenario where a database is a user a lot of stress/load. Which service would you use to alleviate this?

• Elasticache is a good choice if your database is particularly read-heavy and not prone to frequent changing
• Redshift is a good choice if your database is feeling stress because management keeps running OLAP (Online Analytic Transactions) transaction on it