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CACHING (ELASTICACHE)

Caching: ElastiCache (Redis)

DOWNLOADING CONCEPT: 1. THE NEED FOR SPEED...
  • ↳Databases read from disk.
  • ↳Even with fast SSDs, reading from a disk takes milliseconds.
  • ↳In the world of high-frequency trading, gaming leaderboards, or viral social media feeds, milliseconds are too slow.
Amazon ElastiCache
  • ↳offers fully managed Redis and Memcached.
  • ↳These are *In-Memory* databases.
  • ↳They store data entirely in RAM, delivering microsecond latency.
  • ↳Because RAM is expensive, you don't use ElastiCache as your primary database; you use it alongside RDS or DynamoDB to cache frequently accessed data.
▲ LIVE INCIDENTYou implemented Lazy Loading caching for a popular news website. However, when you update a news article in the backend database, the website still shows the old, outdated article for 24 hours.
sre@arena:~/cloud-cache
sre@arena:~$ redis-cli -h cache.my-cluster.aws.com get article:123