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While this loads — worth knowing
ElastiCache RedisnotElastiCache Memcached
Redis has data structures — sorted sets, counters, pub/sub. Memcached has plain keys and nothing else.
Loading…
While this loads — worth knowing
Redis has data structures — sorted sets, counters, pub/sub. Memcached has plain keys and nothing else.
Architecture pattern
when one thing happens and several unrelated things must follow
The producer announces that something happened and stops caring. Each consumer subscribes to what it needs. Adding a fifth consumer later touches nothing that already exists, which is the whole reason to do it this way.
In the order a request or a record moves through it. Each one links to the page that explains it.
Phrases that, when you meet them in a scenario, mean this shape rather than another. They are the tell, and they are what an exam question is built around.
No single place shows you the whole flow, and debugging becomes tracing rather than reading.
Every shape has one. A design decision with no stated downside is usually a decision nobody has finished making.
These run through some of the same services, which is exactly why a brief that fits one can look like it fits another.
Reading a shape and producing one from a scenario that never names a service are different skills, and the exam asks for the second. The scenarios give you the brief; you draw the architecture and it is scored against what the brief requires.