== Use case ==
Though there are many usecases of ZooKeeper. The most common ones are: Building a reliable configuration service A Distributed Lock Service Only single process may hold the lock
== Not to Use === It is important to know when not to use zookeeper. You should not use it to store big data because the number of copies == number of nodes. All data is loaded in ram too. Also, there is a Network load for transfer all data to all nodes.
Use ZooKeeper when you require extremely strong consistency
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