HADOOP YARN (1)

What is HADOOP YARN? The full name of Yarn is the basic concept of Yet Another Resource Negotiator (Resource Manager) Container container is a layer of abstraction of resources by Yarn. (CPU core, memory and other computing resources) the container is started and managed by NodeManager, and the container monitored by it is managed by ResureceManager scheduling ResourceManager (RM), which includes a timing scheduler (scheduler) and an application manager (ApplicationManager) scheduler to allocate resources, and the application manager monitors the application. Every time a job is submitted by ApplicationMaster, Appmaster applies for resources from Resourcemanager and sends the running program to the container to start. Nodemanager is responsible for the management of containers, monitoring the use of resources, and providing reports on the use of resources to ResourceManager. Program submission process 1. Client submits Application2 to Yarn. ResourceManager communicates to NodeManager, assigns the first container to Appmaster. Appmaster splits jobs and applies to ResourceManager for container 4. Appmaster communicates with NodeManager and distributes jobs to containers. 5. The container sends a heartbeat to Appmaster 6. When the program ends, Appmaster logs out resources to ResourceManager