What ZooKeeper Does

What ZooKeeper Does

ZooKeeper provides a very simple interface and services. ZooKeeper brings these key benefits:

• Fast.ZooKeeper is especially fast with workloads where reads to the data are more common than writes. The ideal read/write ratio is about 10:1.
• Reliable.ZooKeeper is replicated over a set of hosts (called an ensemble) and the servers are aware of each other. As long as a critical mass of servers is available, the ZooKeeper service will also be available. There is no single point of failure.
• Simple.ZooKeeper maintain a standard hierarchical name space, similar to files and directories.
• Ordered.The service maintains a record of all transactions, which can be used for higher-level abstractions, like synchronization primitives.

What is ZooKeeper?

What is ZooKeeper?

ZooKeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services. All of these kinds of services are used in some form or another by distributed applications. Each time they are implemented there is a lot of work that goes into fixing the bugs and race conditions that are inevitable. Because of the difficulty of implementing these kinds of services, applications initially usually skimp on them ,which make them brittle in the presence of change and difficult to manage. Even when done correctly, different implementations of these services lead to management complexity when the applications are deployed.

Learn more about ZooKeeper on the ZooKeeper Wiki.