Package org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.resources

Class ResourceHandlerChain

java.lang.Object

org.apache.hadoop.yarn.server.nodemanager.containermanager.linux.resources.ResourceHandlerChain

All Implemented Interfaces:

ResourceHandler

@Private
@Unstable
public class ResourceHandlerChain
extends Object
implements ResourceHandler

A helper class to delegate funcationality to a 'chain' of ResourceHandler(s)

Constructor Summary

Constructors

Constructor	Description
ResourceHandlerChain(List<ResourceHandler> resourceHandlers)

Method Summary

Modifier and Type	Method	Description
List<PrivilegedOperation>	bootstrap(org.apache.hadoop.conf.Configuration configuration)	Bootstrap resource susbsystem.
List<ResourceHandler>	getResourceHandlerList()
List<PrivilegedOperation>	postComplete(org.apache.hadoop.yarn.api.records.ContainerId containerId)	Perform any tasks necessary after container completion.
List<PrivilegedOperation>	preStart(Container container)	Prepare a resource environment for container launch
List<PrivilegedOperation>	reacquireContainer(org.apache.hadoop.yarn.api.records.ContainerId containerId)	Require state for container that was already launched
List<PrivilegedOperation>	teardown()	Teardown environment for resource subsystem if requested.
String	toString()
List<PrivilegedOperation>	updateContainer(Container container)	Update state for container that was already launched

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

ResourceHandlerChain

public ResourceHandlerChain(List<ResourceHandler> resourceHandlers)

Method Details

bootstrap

public List<PrivilegedOperation> bootstrap(org.apache.hadoop.conf.Configuration configuration)
                                    throws ResourceHandlerException

Description copied from interface: ResourceHandler

Bootstrap resource susbsystem.

Specified by:

bootstrap in interface ResourceHandler

Returns:

(possibly empty) list of operations that require elevated privileges

Throws:

ResourceHandlerException

preStart

public List<PrivilegedOperation> preStart(Container container)
                                   throws ResourceHandlerException

Description copied from interface: ResourceHandler

Prepare a resource environment for container launch

Specified by:

preStart in interface ResourceHandler

Parameters:

container - Container being launched

Returns:

(possibly empty) list of operations that require elevated privileges e.g a) create a custom cgroup b) add pid for container to tasks file for a cgroup.

Throws:

ResourceHandlerException

reacquireContainer

public List<PrivilegedOperation> reacquireContainer(org.apache.hadoop.yarn.api.records.ContainerId containerId)
                                             throws ResourceHandlerException

Description copied from interface: ResourceHandler

Require state for container that was already launched

Specified by:

reacquireContainer in interface ResourceHandler

Parameters:

containerId - id of the container being reacquired.

Returns:

(possibly empty) list of operations that require elevated privileges

Throws:

ResourceHandlerException

updateContainer

public List<PrivilegedOperation> updateContainer(Container container)
                                          throws ResourceHandlerException

Description copied from interface: ResourceHandler

Update state for container that was already launched

Specified by:

updateContainer in interface ResourceHandler

Parameters:

container - the container being updated.

Returns:

(possibly empty) list of operations that require elevated privileges

Throws:

ResourceHandlerException

postComplete

public List<PrivilegedOperation> postComplete(org.apache.hadoop.yarn.api.records.ContainerId containerId)
                                       throws ResourceHandlerException

Description copied from interface: ResourceHandler

Perform any tasks necessary after container completion.

Specified by:

postComplete in interface ResourceHandler

Parameters:

containerId - of the container that was completed.

Returns:

(possibly empty) list of operations that require elevated privileges

Throws:

ResourceHandlerException

teardown

public List<PrivilegedOperation> teardown()
                                   throws ResourceHandlerException

Description copied from interface: ResourceHandler

Teardown environment for resource subsystem if requested. This method needs to be used with care since it could impact running containers.

Specified by:

teardown in interface ResourceHandler

Returns:

(possibly empty) list of operations that require elevated privileges

Throws:

ResourceHandlerException

getResourceHandlerList

@VisibleForTesting
public List<ResourceHandler> getResourceHandlerList()

toString

public String toString()

Overrides:

toString in class Object