What is the difference between Mutator and Shared Mutator?
In the specs for Mutator, there is a "flush_interval" (Auto-flush interval in milliseconds; 0 disables it.) parameter.
In the specs for Shared Mutator, it states:
WARNING: Shared mutators sacrifice write durability guarantee because they buffer and flush mutations on a periodic time interval and the set_ methods return without knowing if the mutations succeeded or failed.
So, what is the difference if both have flush intervals?
Further, are both thread-safe (in Java)?
Also, which is more efficient in terms of performance?