I'm trying to wrap my head around an example of a single value that would be accessed ~1-million times a second that would be cached and served by Redis, and not cached closer to the consumer (such as a web server).
And it's not uncommon for backend services to access internal data via REST endpoints.
That is a trade-off, and gets to the meat of my question.
If I understand the anti-pattern recommendation, if you have a single data item that needs to be accessed at a very high throughput rate, if you choose to use REDIS, it's best to have n-copies indexed by different keys, in order to properly distribute the data across multiple-shards to have that specific through-put.
The tradeoff would be having one-copy of the data (a single key in REDIS) and the complexity of caching it locally, OR have it cached at REDIS, and the complexity of managing having multiple copies of the same data in REDIS with equally distributed keys.
My original question--what would be a usecase for choosing the latter.