org.apache.hadoop.yarn.client.api

Class AMRMClient.ContainerRequest

java.lang.Object

org.apache.hadoop.yarn.client.api.AMRMClient.ContainerRequest

Enclosing class:

AMRMClient<T extends AMRMClient.ContainerRequest>

public static class AMRMClient.ContainerRequest
extends Object

Object to represent a single container request for resources. Scheduler documentation should be consulted for the specifics of how the parameters are honored. By default, YARN schedulers try to allocate containers at the requested locations but they may relax the constraints in order to expedite meeting allocations limits. They first relax the constraint to the same rack as the requested node and then to anywhere in the cluster. The relaxLocality flag may be used to disable locality relaxation and request containers at only specific locations. The following conditions apply.

• Within a priority, all container requests must have the same value for locality relaxation. Either enabled or disabled.
• If locality relaxation is disabled, then across requests, locations at different network levels may not be specified. E.g. its invalid to make a request for a specific node and another request for a specific rack.
• If locality relaxation is disabled, then only within the same request, a node and its rack may be specified together. This allows for a specific rack with a preference for a specific node within that rack.

To re-enable locality relaxation at a given priority, all pending requests with locality relaxation disabled must be first removed. Then they can be added back with locality relaxation enabled. All getters return immutable values.

Constructor Summary

Constructors

Constructor and Description
ContainerRequest(Resource capability, String[] nodes, String[] racks, Priority priority) Instantiates a AMRMClient.ContainerRequest with the given constraints and locality relaxation enabled.
ContainerRequest(Resource capability, String[] nodes, String[] racks, Priority priority, boolean relaxLocality) Instantiates a AMRMClient.ContainerRequest with the given constraints.
ContainerRequest(Resource capability, String[] nodes, String[] racks, Priority priority, boolean relaxLocality, String nodeLabelsExpression) Instantiates a AMRMClient.ContainerRequest with the given constraints.

Method Summary

Modifier and Type	Method and Description
Resource	getCapability()
String	getNodeLabelExpression()
List<String>	getNodes()
Priority	getPriority()
List<String>	getRacks()
boolean	getRelaxLocality()
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

ContainerRequest

public ContainerRequest(Resource capability,
                        String[] nodes,
                        String[] racks,
                        Priority priority)

Instantiates a AMRMClient.ContainerRequest with the given constraints and locality relaxation enabled.

Parameters:

capability - The Resource to be requested for each container.

nodes - Any hosts to request that the containers are placed on.

racks - Any racks to request that the containers are placed on. The racks corresponding to any hosts requested will be automatically added to this list.

priority - The priority at which to request the containers. Higher priorities have lower numerical values.

ContainerRequest

public ContainerRequest(Resource capability,
                        String[] nodes,
                        String[] racks,
                        Priority priority,
                        boolean relaxLocality)

Instantiates a AMRMClient.ContainerRequest with the given constraints.

Parameters:

capability - The Resource to be requested for each container.

nodes - Any hosts to request that the containers are placed on.

racks - Any racks to request that the containers are placed on. The racks corresponding to any hosts requested will be automatically added to this list.

priority - The priority at which to request the containers. Higher priorities have lower numerical values.

relaxLocality - If true, containers for this request may be assigned on hosts and racks other than the ones explicitly requested.

ContainerRequest

public ContainerRequest(Resource capability,
                        String[] nodes,
                        String[] racks,
                        Priority priority,
                        boolean relaxLocality,
                        String nodeLabelsExpression)

Instantiates a AMRMClient.ContainerRequest with the given constraints.

Parameters:

capability - The Resource to be requested for each container.

nodes - Any hosts to request that the containers are placed on.

racks - Any racks to request that the containers are placed on. The racks corresponding to any hosts requested will be automatically added to this list.

priority - The priority at which to request the containers. Higher priorities have lower numerical values.

relaxLocality - If true, containers for this request may be assigned on hosts and racks other than the ones explicitly requested.

nodeLabelsExpression - Set node labels to allocate resource, now we only support asking for only a single node label

Method Detail

getCapability

public Resource getCapability()

getNodes

public List<String> getNodes()

getRacks

public List<String> getRacks()

getPriority

public Priority getPriority()

getRelaxLocality

public boolean getRelaxLocality()

getNodeLabelExpression

public String getNodeLabelExpression()

toString

public String toString()

Overrides:

toString in class Object