Package org.apache.drill.yarn.zk

Interface between the Application Master and ZooKeeper.

See: Description

Class Summary

Class	Description
AMRegistry	Register this App Master in ZK to prevent duplicates.
TestAmRegistration
TestZkRegistry	Tests for the AM version of the cluster coordinator.
TestZkRegistry.TestTask
ZKClusterCoordinator	Manages cluster coordination utilizing zookeeper.
ZKClusterCoordinatorDriver	Driver class for the ZooKeeper cluster coordinator.
ZKRegistry	AM-specific implementation of a Drillbit registry backed by ZooKeeper.
ZKRegistry.AckEvent
ZKRegistry.DrillbitTracker	State of each Drillbit that we've discovered through ZK or launched via the AM.

Enum Summary

Enum	Description
ZKRegistry.DrillbitTracker.State	A Drillbit can be in one of four states.

Exception Summary

Exception	Description
ZKConfigException
ZKRuntimeException

Package org.apache.drill.yarn.zk Description

Interface between the Application Master and ZooKeeper. Classes here manage two registrations: Drillbits and the AM itself.

Drillbit registration is used to confirm that Drillbits have indeed come online. If Drillbits fail to come online, then the AM concludes that somethign went wrong. If Drilbits drop offline unexpectedly, the AM concludes that the Drillbit is sick and restarts it.

The AM registry prevents two AMs from attempting to manage the same cluster.