org.apache.flink.runtime.taskexecutor.slot

Class TaskSlotTable

java.lang.Object

org.apache.flink.runtime.taskexecutor.slot.TaskSlotTable

All Implemented Interfaces:

TimeoutListener<AllocationID>

public class TaskSlotTable
extends Object
implements TimeoutListener<AllocationID>

Container for multiple TaskSlot instances. Additionally, it maintains multiple indices for faster access to tasks and sets of allocated slots.

The task slot table automatically registers timeouts for allocated slots which cannot be assigned to a job manager.

Before the task slot table can be used, it must be started via the start(org.apache.flink.runtime.taskexecutor.slot.SlotActions) method.

Constructor Summary

Constructors

Constructor and Description
TaskSlotTable(Collection<ResourceProfile> resourceProfiles, TimerService<AllocationID> timerService)

Method Summary

Modifier and Type	Method and Description
boolean	addTask(Task task) Add the given task to the slot identified by the task's allocation id.
boolean	allocateSlot(int index, JobID jobId, AllocationID allocationId, Time slotTimeout) Allocate the slot with the given index for the given job and allocation id.
SlotReport	createSlotReport(ResourceID resourceId)
boolean	existsActiveSlot(JobID jobId, AllocationID allocationId) Check whether there exists an active slot for the given job and allocation id.
int	freeSlot(AllocationID allocationId) Try to free the slot.
int	freeSlot(AllocationID allocationId, Throwable cause) Tries to free the slot.
Iterator<AllocationID>	getActiveSlots(JobID jobId) Return an iterator of active slots (their application ids) for the given job id.
Iterator<TaskSlot>	getAllocatedSlots(JobID jobId) Return an iterator of allocated slots for the given job id.
AllocationID	getCurrentAllocation(int index) Get the current allocation for the task slot with the given index.
Task	getTask(ExecutionAttemptID executionAttemptID) Get the task for the given execution attempt id.
Iterator<Task>	getTasks(JobID jobId) Return an iterator over all tasks for a given job.
boolean	hasAllocatedSlots(JobID jobId) Check whether the job has allocated (not active) slots.
boolean	isAllocated(int index, JobID jobId, AllocationID allocationId) Check whether the slot for the given index is allocated for the given job and allocation id.
boolean	isSlotFree(int index) Check whether the task slot with the given index is free.
boolean	isValidTimeout(AllocationID allocationId, UUID ticket) Check whether the timeout with ticket is valid for the given allocation id.
boolean	markSlotActive(AllocationID allocationId) Marks the slot under the given allocation id as active.
boolean	markSlotInactive(AllocationID allocationId, Time slotTimeout) Marks the slot under the given allocation id as inactive.
void	notifyTimeout(AllocationID key, UUID ticket) Notify the listener about the timeout for an event identified by key.
Task	removeTask(ExecutionAttemptID executionAttemptID) Remove the task with the given execution attempt id from its task slot.
void	start(SlotActions initialSlotActions) Start the task slot table with the given slot actions and slot timeout value.
void	stop() Stop the task slot table.

Methods inherited from class java.lang.Object

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

Constructor Detail

TaskSlotTable

public TaskSlotTable(Collection<ResourceProfile> resourceProfiles,
                     TimerService<AllocationID> timerService)

Method Detail

start

public void start(SlotActions initialSlotActions)

Start the task slot table with the given slot actions and slot timeout value.

Parameters:

initialSlotActions - to use for slot actions

stop

public void stop()

Stop the task slot table.

createSlotReport

public SlotReport createSlotReport(ResourceID resourceId)

allocateSlot

public boolean allocateSlot(int index,
                            JobID jobId,
                            AllocationID allocationId,
                            Time slotTimeout)

Allocate the slot with the given index for the given job and allocation id. Returns true if the slot could be allocated. Otherwise it returns false;

Parameters:

index - of the task slot to allocate

jobId - to allocate the task slot for

allocationId - identifying the allocation

slotTimeout - until the slot times out

Returns:

True if the task slot could be allocated; otherwise false

markSlotActive

public boolean markSlotActive(AllocationID allocationId)
                       throws SlotNotFoundException

Marks the slot under the given allocation id as active. If the slot could not be found, then a SlotNotFoundException is thrown.

Parameters:

allocationId - to identify the task slot to mark as active

Returns:

True if the slot could be marked active; otherwise false

Throws:

SlotNotFoundException - if the slot could not be found for the given allocation id

markSlotInactive

public boolean markSlotInactive(AllocationID allocationId,
                                Time slotTimeout)
                         throws SlotNotFoundException

Marks the slot under the given allocation id as inactive. If the slot could not be found, then a SlotNotFoundException is thrown.

Parameters:

allocationId - to identify the task slot to mark as inactive

slotTimeout - until the slot times out

Returns:

True if the slot could be marked inactive

Throws:

SlotNotFoundException - if the slot could not be found for the given allocation id

freeSlot

public int freeSlot(AllocationID allocationId)
             throws SlotNotFoundException

Try to free the slot. If the slot is empty it will set the state of the task slot to free and return its index. If the slot is not empty, then it will set the state of the task slot to releasing, fail all tasks and return -1.

Parameters:

allocationId - identifying the task slot to be freed

Returns:

Index of the freed slot if the slot could be freed; otherwise -1

Throws:

SlotNotFoundException - if there is not task slot for the given allocation id

freeSlot

public int freeSlot(AllocationID allocationId,
                    Throwable cause)
             throws SlotNotFoundException

Tries to free the slot. If the slot is empty it will set the state of the task slot to free and return its index. If the slot is not empty, then it will set the state of the task slot to releasing, fail all tasks and return -1.

Parameters:

allocationId - identifying the task slot to be freed

cause - to fail the tasks with if slot is not empty

Returns:

Index of the freed slot if the slot could be freed; otherwise -1

Throws:

SlotNotFoundException - if there is not task slot for the given allocation id

isValidTimeout

public boolean isValidTimeout(AllocationID allocationId,
                              UUID ticket)

Check whether the timeout with ticket is valid for the given allocation id.

Parameters:

allocationId - to check against

ticket - of the timeout

Returns:

True if the timeout is valid; otherwise false

isAllocated

public boolean isAllocated(int index,
                           JobID jobId,
                           AllocationID allocationId)

Check whether the slot for the given index is allocated for the given job and allocation id.

Parameters:

index - of the task slot

jobId - for which the task slot should be allocated

allocationId - which should match the task slot's allocation id

Returns:

True if the given task slot is allocated for the given job and allocation id

existsActiveSlot

public boolean existsActiveSlot(JobID jobId,
                                AllocationID allocationId)

Check whether there exists an active slot for the given job and allocation id.

Parameters:

jobId - of the allocated slot

allocationId - identifying the allocation

Returns:

True if there exists a task slot which is active for the given job and allocation id.

isSlotFree

public boolean isSlotFree(int index)

Check whether the task slot with the given index is free.

Parameters:

index - of the task slot

Returns:

True if the task slot is free; otherwise false

hasAllocatedSlots

public boolean hasAllocatedSlots(JobID jobId)

Check whether the job has allocated (not active) slots.

Parameters:

jobId - for which to check for allocated slots

Returns:

True if there are allocated slots for the given job id.

getAllocatedSlots

public Iterator<TaskSlot> getAllocatedSlots(JobID jobId)

Return an iterator of allocated slots for the given job id.

Parameters:

jobId - for which to return the allocated slots

Returns:

Iterator of allocated slots.

getActiveSlots

public Iterator<AllocationID> getActiveSlots(JobID jobId)

Return an iterator of active slots (their application ids) for the given job id.

Parameters:

jobId - for which to return the active slots

Returns:

Iterator of allocation ids of active slots

addTask

public boolean addTask(Task task)
                throws SlotNotFoundException,
                       SlotNotActiveException

Add the given task to the slot identified by the task's allocation id.

Parameters:

task - to add to the task slot with the respective allocation id

Returns:

True if the task could be added to the task slot; otherwise false

Throws:

SlotNotFoundException - if there was no slot for the given allocation id

SlotNotActiveException - if there was no slot active for task's job and allocation id

removeTask

public Task removeTask(ExecutionAttemptID executionAttemptID)

Remove the task with the given execution attempt id from its task slot. If the owning task slot is in state releasing and empty after removing the task, the slot is freed via the slot actions.

Parameters:

executionAttemptID - identifying the task to remove

Returns:

The removed task if there is any for the given execution attempt id; otherwise null

getTask

public Task getTask(ExecutionAttemptID executionAttemptID)

Get the task for the given execution attempt id. If none could be found, then return null.

Parameters:

executionAttemptID - identifying the requested task

Returns:

The task for the given execution attempt id if it exist; otherwise null

getTasks

public Iterator<Task> getTasks(JobID jobId)

Return an iterator over all tasks for a given job.

Parameters:

jobId - identifying the job of the requested tasks

Returns:

Iterator over all task for a given job

getCurrentAllocation

public AllocationID getCurrentAllocation(int index)

Get the current allocation for the task slot with the given index.

Parameters:

index - identifying the slot for which the allocation id shall be retrieved

Returns:

Allocation id of the specified slot if allocated; otherwise null

notifyTimeout

public void notifyTimeout(AllocationID key,
                          UUID ticket)

Description copied from interface: TimeoutListener

Notify the listener about the timeout for an event identified by key. Additionally the method is called with the timeout ticket which allows to identify outdated timeout events.

Specified by:

notifyTimeout in interface TimeoutListener<AllocationID>

Parameters:

key - identifying the timed out event

ticket - used to check whether the timeout is still valid