Netflix Data Management & Platform Libraries Tools |Glossary Part 3

By Flux7 Labs
February 28, 2014

This is Part 3 of our series on Netflix open-source tools. You can find Part 1 here and Part 2 here.

Netflix In-Memory Data Management Tools


Netflix handles billions of daily requests that require access to video metadata. Given the huge number of stored videos, data is stored on the traffic-handling server’s RAM to reduce latency. Data is packaged and shipped using two applications:

  • Video Metadata Platform (VMS) packages video’s synopses, titles, artwork, and streams.

  • Netflix-Graph stores data as a directed graph of the relationship between entities like video characters and tags. It stores any type of data that can be “phrased” as directed graph.


Zeno is a highly optimized framework that helps manage and update the giga-bytes of constantly changing data that are replicated in thousands of servers. It provides:

  • Duplicate dataset removal.

  • Efficient data deserialization.

  • Powerful debug tools.

  • Improved development-team agility providing a clear line of separation between a data model and operations.

  • The ability to maintain minimal changes required to keep data up to date.

Netflix Platform Libraries Tools


Archaius is a configuration management library focused on dynamic properties from multiple configuration stores. It’s a Java library that provides APIs for dynamic access to properties. It provides:

  • Dynamic properties of specific values.

  • A polling framework for dynamic configuration sources.

  • Ready-made configuration sources.

  • Context management.

  • High throughput and thread-safe configurations.

  • Scala wrappers.


Denominator is a portable Java library for processing DNS clouds. It has pluggable backends for:

  • AWS Route 53

  • Neustar Ultra

  • DynECT

  • Rackspace Cloud DNS

  • Openstack Designate


Feign is a Java-to-HTTP client binder that allows binding with minimal code and overhead. It provides:

  • Creation of customized components.

  • Production of multiple interfaces.

  • Quick integration with other open-source projects.


Karyon is a framework and library that serves as a blueprint for implementing cloud-ready web services and that can clone fine-grained web services and applications. Karyon’s blueprint includes:

  • Bootstrapping, Libraries, and Lifecycle Management.

  • Runtime Insights and Diagnostics.

  • Pluggable Web Resources.

  • Cloud readiness.

Karyon is based on two main entities:

  • Component is a standalone entity that’s required for the application to work, but is not a direct dependency of the application.

  • Application is a class inside the service. There can only be one application for each service and all components are initialized before the application is initialized.


Ribbon is a library that supports inter-process communication in the cloud. Features include:

  • Pluggable load balancing rules.

  • Service discovery integration.

  • Built-in failure resiliency.

  • Load balancer integration with clients.

It currently has 3 sub-projects:

  • ribbon-core

  • ribbon-eureka

  • ribbon-httpclient


Servo is an application-monitoring library that generates monitors and metrics. A monitor has a configuration that is a set of key-value pairs. A metric is the value for a given monitor at a specific time.

There are three types of monitors:

  • Gauges are simple monitors that return current values, such as queue size and thread number. Servo gauge implementations include BasicGauge, MinGauge, MaxGauge and NumberGauge.

  • Counters come in three flavors: Basic, Resettable and PeakRate.

  • Timers indicate time taken for a particular event..


Blitz4j is a logging framework built on top of log4j. It allows high-scalable logging while maintaining high performance. Features include:

  • Event monitoring.

  • Business intelligence reporting.

  • Debugging.

Blitz4j mitigates data loss and provides a mechanism to summarize data during log storms.


Governator is a library of extensions and utilities that extend Google Guice capabilities. Guice is a dependency injection container open-sourced by Google.