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Re:Please stop calling databases CP or AP (2015) by Autowired on Monday September 07, 2020 @10:23AM (#24399589)
Always wondered, if the CAP theorem does not account for latency, one assumes infinite latency does not impact availability. Shouldn't then be possible to define a theoretical system with an infinite buffer that, in the event of a network partition, will simply keep all incoming requests on hold (infinitely or until the partition is undone), satisfying CAP?

I know this is a useless construct in practice, and there is probably a flaw in my reasoning, but it seems to me that you have to establish a non-infinite timeout for the proof to be consistent.

Re:Please stop calling databases CP or AP (2015) by ses1984 on Monday September 07, 2020 @10:34AM (#24399672)
If there is a partition and you want to execute a write on both sides of the partition, both sides can wait, but eventually one side wins and the other side gets back a failure, so the db turned out not to be available on that side. At least that's my interpretation.
Re:Please stop calling databases CP or AP (2015) by Autowired on Monday September 07, 2020 @10:53AM (#24399807)
Well, for a system to be consistent (in the meaning of CAP) AND available, the problem with the concurrent writes would have to be solved anyway (i.e. via distributed locking), so I don't think this would be an issue after a partition event.
Re:Please stop calling databases CP or AP (2015) by ses1984 on Monday September 07, 2020 @11:51AM (#24400218)
That assumes a particular locking system, what if you're using optimistic locking?