We've explored how the process of updating alice's e-mail address would work at the consistency levels ONE, ALL, and QUORUM. But what consistency levels should the MyStatus application actually use?
We recognized earlier that in the case where alice updates her own user profile and then views the results, eventual consistency is undesirable: if she sees an outdated copy of her profile, it may appear that her e-mail address update did not work at all. So, we will want to ensure that from alice's standpoint, changes to her profile are immediately consistent.
We've seen that of the two levels that ensure immediate consistency, QUORUM has considerably more appeal from the perspective of fault tolerance and ...
