Introduction
Are you looking for a distributed coordination service? Look no further than Apache ZooKeeper or etcd. These two popular, open-source, distributed coordination services serve the same purpose but are different in terms of features and functionality. In this article, we will compare the two based on performance, scalability, and ease of use, so you can make an informed decision on which one to choose.
Apache ZooKeeper
Apache ZooKeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services. It was initially developed by Yahoo! and later became a contributory Apache project in 2008. ZooKeeper's architecture is based on a simple and fast replicated state management framework, which enables it to provide high-performance and high-availability services.
Performance
ZooKeeper has a small footprint, demanding only a few hundred MBs of RAM and little disk space. It can handle a large number of concurrent clients while maintaining low latency. ZooKeeper can handle more than 100k transactions per second on a read-heavy workload and can go as high as 10k transactions per second on a write-heavy workload.
Scalability
ZooKeeper is designed to scale up by adding more servers to the ensemble. Once you add a new server to the ensemble, the cluster automatically redistributes the load. ZooKeeper can handle up to five thousand nodes per ensemble, although it might not be easy to manage a cluster of this size.
Ease of use
ZooKeeper requires some level of technical proficiency to set up and configure. The configuration options are extensive, and the documentation can be overwhelming. However, once ZooKeeper is up and running, it is relatively easy to use.
etcd
etcd is a distributed key-value store that provides a reliable way to store data across a cluster of machines. It was initially developed by CoreOS in 2013 and later became a CNCF project in 2018. etcd's architecture is based on the Raft consensus algorithm that provides fault-tolerance and strong consistency.
Performance
etcd is a lightweight, efficient system that can handle a high read/write throughput. On its default configuration, etcd can handle around 10k to 20k write requests per second and over 100k requests per second for read requests.
Scalability
etcd is scalable and can handle thousands of nodes across clusters. etcd's supporting architecture allows for automatic rebalancing and reconfiguration of nodes, ensuring that the system is always available and data is always accessible.
Ease of use
etcd is easier to use than ZooKeeper. The default configuration is easy to set up, and the API is simple to use. etcd also has good documentation and community support.
Conclusion
So, which one is better for you? It ultimately depends on your individual requirements. If you are willing to trade off ease of use for high-performance and scalability, then ZooKeeper is an excellent option. On the other hand, if you value ease of use, a simpler configuration, and still want high-performance and scalability, then etcd might be the better option.
Regardless of your choice, both Apache ZooKeeper and etcd are strong contenders for distributed coordination services.
References:
- Apache ZooKeeper official documentation https://zookeeper.apache.org/doc/current/
- etcd official documentation: https://etcd.io/docs/
- A comparison between etcd and ZooKeeper by Elton Stoneman: https://www.docker.com/blog/etcd-vs-zookeeper/