Apache Hadoop YARN (Yet Another Resource Negotiator)
Apache Hadoop YARN (Yet Another Resource Negotiator) is a cluster management technology.
YARN is one of the key features in the second-generation Hadoop 2 version of the Apache Software Foundation's open source distributed processing framework. Originally described by Apache as a redesigned resource manager, YARN is now characterized as a large-scale, distributed operating system for big data applications.
In 2012, YARN became a sub-project of the larger Apache Hadoop project. Sometimes called MapReduce 2.0, YARN is a software rewrite that decouples MapReduce's resource management and scheduling capabilities from the data processing component, enabling Hadoop to support more varied processing approaches and a broader array of applications. For example, Hadoop clusters can now run interactive querying and streaming data applications simultaneously with MapReduce batch jobs. The original incarnation of Hadoop closely paired the Hadoop Distributed File System (HDFS) with the batch-oriented MapReduce programming framework, which handles resource management and job scheduling on Hadoop systems and supports the parsing and condensing of data sets in parallel.
YARN combines a central resource manager that reconciles the way applications use Hadoop system resources with node manager agents that monitor the processing operations of individual cluster nodes. Running on commodity hardware clusters, Hadoop has attracted particular interest as a staging area and data store for large volumes of structured and unstructured data intended for use in analytics applications. Separating HDFS from MapReduce with YARN makes the Hadoop environment more suitable for operational applications that can't wait for batch jobs to finish.
See also: yacc (yet another compiler compiler)