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I thought nosql movement was about distributed systems, cap and all that. What does this "active-active-active" even mean? No consistency and no availability guaranties I presume?

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I may be reading this wrong, but I think they are purposing a not C not A not P solution... thats "ok" fast? They explain how to make a single mysql instance run as key-value but I dont understand how it becomes master-master or cross DCs. Wonder if they run Jepsen or do any partition tolerance tests given their mentioning it.

AFAIK the only way to do 3 masters in vanilla mysql is ring replication. That means C is B's slave, B is A's, A is C's. If that's what they do, then yeah, it's a noCAP deployment. No consistency if you insert the same UUID at the same time into 2 masters. No availability unless you implement it yourself by retry to another master. No partition tolerance, because if you break one replication link, half the writes are not replicated between other servers and you can't really both reconfigure the ring and replay the transactions.

(Yes, they say active-active-active, not master-master-master, but then they say across DCs... It could be just M-S-S with config switch on failover, but for me the post suggests it's not that)

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