Suppose you set up a Redis cluster with one master and two slaves. Two clients are connected to each of the slaves. Both clients make conflicting changes at the same time:
What happens if these changes are replicated to Master at around the same time? Are they just applied to Master in the order they are received, then replicated back down?
What if transactions are used? Is the result eventually consistent, i.e. does Master resolve the conflict by applying the transactions in some order, then replicate the resolution down?
I don't expect perfect consistency from a distributed cache, but I do want to understand the fine points so that I use caching well. The application I'm working on uses the distributed cache for coordination among worker threads/processes. For example, when one worker processes an item, it puts a key in the cache with an expiration of 1 minute telling other workers not to process the same item. It's acceptable if two or three workers end up processing the same item, but this mechanism prevents infinite reprocessing.