org.apache.flink.runtime.jobmanager.scheduler

Class CoLocationConstraint

java.lang.Object

org.apache.flink.runtime.jobmanager.scheduler.CoLocationConstraint

public class CoLocationConstraint
extends Object

A CoLocationConstraint manages the location of a set of tasks (Execution Vertices). In co-location groups, the different subtasks of different JobVertices need to be executed on the same slot. This is realized by creating a special shared slot that holds these tasks.

This class tracks the location and the shared slot for this set of tasks.

Method Summary

Modifier and Type	Method and Description
AbstractID	getGroupId() Gets the ID that identifies the co-location group.
TaskManagerLocation	getLocation() Gets the location assigned to this slot.
SlotRequestId	getSlotRequestId() Returns the currently assigned slot request id identifying the slot to which tasks belonging to this co-location constraint will be deployed to.
boolean	isAssigned() Checks whether the location of this constraint has been assigned.
void	lockLocation(TaskManagerLocation taskManagerLocation) Locks the location of this slot.
void	setSlotRequestId(SlotRequestId slotRequestId) Sets the slot request id of the currently assigned slot to the co-location constraint.
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

getGroupId

public AbstractID getGroupId()

Gets the ID that identifies the co-location group.

Returns:

The ID that identifies the co-location group.

isAssigned

public boolean isAssigned()

Checks whether the location of this constraint has been assigned. The location is locked via the lockLocation(TaskManagerLocation) method.

Returns:

True if the location has been assigned, false otherwise.

getLocation

public TaskManagerLocation getLocation()

Gets the location assigned to this slot. This method only succeeds after the location has been locked via the lockLocation(TaskManagerLocation) method and isAssigned() returns true.

Returns:

The instance describing the location for the tasks of this constraint.

Throws:

IllegalStateException - Thrown if the location has not been assigned, yet.

lockLocation

public void lockLocation(TaskManagerLocation taskManagerLocation)

Locks the location of this slot. The location can be locked only once and only after a shared slot has been assigned.

Note: This method exists for compatibility reasons with the new SlotPool.

Parameters:

taskManagerLocation - to lock this co-location constraint to

setSlotRequestId

public void setSlotRequestId(@Nullable
                             SlotRequestId slotRequestId)

Sets the slot request id of the currently assigned slot to the co-location constraint. All other tasks belonging to this co-location constraint will be deployed to the same slot.

Parameters:

slotRequestId - identifying the assigned slot for this co-location constraint

getSlotRequestId

@Nullable
public SlotRequestId getSlotRequestId()

Returns the currently assigned slot request id identifying the slot to which tasks belonging to this co-location constraint will be deployed to.

Returns:

Slot request id of the assigned slot or null if none

toString

public String toString()

Overrides:

toString in class Object