A lot of programming tools implement event-driven approach. Apache ZooKeeper isn't an exception for this rule with its system of watchers.
Apache ZooKeeper is very often compared to distributed file system. Because each file system has a feature to deal with file permissions, ZooKeeper, as a kind of file system, can't be different.
Sometimes network latencies can slow down the communication between Apache ZooKeeper and its client. It's one of the reasons of possible use of asynchronous operations for zNodes manipulations.
Until now we've seen how to create zNodes. But creation is not the single thing that Apache ZooKeeper does.
Client connects to ZooKeeper server and maintains a session. There are several things to know about ZooKeeper sessions and we'll explore them in this article.
As already told, zNodes are a key part in Apache ZooKeeper. They store information shared among different servers directly (as binary data) or indirectly (as parent directories).
Usually Apache ZooKeeper works in the shadow of more exposed Big Data tools, as Apache Spark or Apache Kafka. However, its role is very important in system architecture.
