org.apache.flink.runtime.jobmaster.slotpool

Class DefaultDeclarativeSlotPool

java.lang.Object

org.apache.flink.runtime.jobmaster.slotpool.DefaultDeclarativeSlotPool

All Implemented Interfaces:

DeclarativeSlotPool

Direct Known Subclasses:

BlocklistDeclarativeSlotPool

public class DefaultDeclarativeSlotPool
extends Object
implements DeclarativeSlotPool

Default DeclarativeSlotPool implementation.

The implementation collects the current resource requirements and declares them at the ResourceManager. Whenever new slots are offered, the slot pool compares the offered slots to the set of available and required resources and only accepts those slots which are required.

Slots which are released won't be returned directly to their owners. Instead, the slot pool implementation will only return them after the idleSlotTimeout has been exceeded by a free slot.

The slot pool will call newSlotsListener whenever newly offered slots are accepted or if an allocated slot should become free after it is being freed.

This class expects 1 of 2 access patterns for changing requirements, which should not be mixed:

1) the legacy approach (used by the DefaultScheduler) tightly couples requirements to reserved slots. When a slot is requested it increases the requirements, when the slot is freed they are decreased again. In the general case what happens is that requirements are increased, a free slot is reserved, (the slot is used for a bit,) the slot is freed, the requirements are reduced. To this end freeReservedSlot(org.apache.flink.runtime.clusterframework.types.AllocationID, java.lang.Throwable, long), releaseSlot(org.apache.flink.runtime.clusterframework.types.AllocationID, java.lang.Exception) and releaseSlots(org.apache.flink.runtime.clusterframework.types.ResourceID, java.lang.Exception) return a ResourceCounter describing which requirement the slot(s) were fulfilling, with the expectation that the scheduler will subsequently decrease the requirements by that amount.

2) The declarative approach (used by the AdaptiveScheduler) in contrast derives requirements exclusively based on what a given job currently requires. It may repeatedly reserve/free slots without any modifications to the requirements.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.runtime.jobmaster.slotpool.DeclarativeSlotPool

DeclarativeSlotPool.NewSlotsListener, DeclarativeSlotPool.NoOpNewSlotsListener

Field Summary

Fields

Modifier and Type	Field and Description
protected org.slf4j.Logger	log
protected AllocatedSlotPool	slotPool

Constructor Summary

Constructors

Constructor and Description
DefaultDeclarativeSlotPool(JobID jobId, AllocatedSlotPool slotPool, java.util.function.Consumer<? super Collection<ResourceRequirement>> notifyNewResourceRequirements, Time idleSlotTimeout, Time rpcTimeout)

Method Summary

Modifier and Type	Method and Description
boolean	containsFreeSlot(AllocationID allocationId) Checks whether the slot pool contains a slot with the given AllocationID and if it is free.
boolean	containsSlots(ResourceID owner) Returns whether the slot pool has a slot registered which is owned by the given TaskExecutor.
void	decreaseResourceRequirementsBy(ResourceCounter decrement) Decreases the resource requirements by decrement.
ResourceCounter	freeReservedSlot(AllocationID allocationId, Throwable cause, long currentTime) Frees the reserved slot identified by the given allocationId.
Collection<? extends SlotInfo>	getAllSlotsInformation() Returns the slot information for all slots (free and allocated slots).
Collection<SlotInfoWithUtilization>	getFreeSlotsInformation() Returns the slot information for all free slots (slots which can be allocated from the slot pool).
Collection<ResourceRequirement>	getResourceRequirements() Returns the current resource requirements.
void	increaseResourceRequirementsBy(ResourceCounter increment) Increases the resource requirements by increment.
Collection<SlotOffer>	offerSlots(Collection<? extends SlotOffer> offers, TaskManagerLocation taskManagerLocation, TaskManagerGateway taskManagerGateway, long currentTime) Offers slots to this slot pool.
void	registerNewSlotsListener(DeclarativeSlotPool.NewSlotsListener newSlotsListener) Registers a listener which is called whenever new slots become available.
Collection<SlotOffer>	registerSlots(Collection<? extends SlotOffer> slots, TaskManagerLocation taskManagerLocation, TaskManagerGateway taskManagerGateway, long currentTime) Registers the given set of slots at the slot pool.
void	releaseIdleSlots(long currentTimeMillis) Releases slots which have exceeded the idle slot timeout and are no longer needed to fulfill the resource requirements.
ResourceCounter	releaseSlot(AllocationID allocationId, Exception cause) Releases the slot specified by allocationId if one exists.
ResourceCounter	releaseSlots(ResourceID owner, Exception cause) Releases all slots belonging to the owning TaskExecutor if it has been registered.
PhysicalSlot	reserveFreeSlot(AllocationID allocationId, ResourceProfile requiredSlotProfile) Reserves the free slot identified by the given allocationId and maps it to the given requiredSlotProfile.
void	setResourceRequirements(ResourceCounter resourceRequirements) Sets the resource requirements to the given resourceRequirements.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected final org.slf4j.Logger log

slotPool

protected final AllocatedSlotPool slotPool

Constructor Detail

DefaultDeclarativeSlotPool

public DefaultDeclarativeSlotPool(JobID jobId,
                                  AllocatedSlotPool slotPool,
                                  java.util.function.Consumer<? super Collection<ResourceRequirement>> notifyNewResourceRequirements,
                                  Time idleSlotTimeout,
                                  Time rpcTimeout)

Method Detail

increaseResourceRequirementsBy

public void increaseResourceRequirementsBy(ResourceCounter increment)

Description copied from interface: DeclarativeSlotPool

Increases the resource requirements by increment.

Specified by:

increaseResourceRequirementsBy in interface DeclarativeSlotPool

Parameters:

increment - increment by which to increase the resource requirements

decreaseResourceRequirementsBy

public void decreaseResourceRequirementsBy(ResourceCounter decrement)

Description copied from interface: DeclarativeSlotPool

Decreases the resource requirements by decrement.

Specified by:

decreaseResourceRequirementsBy in interface DeclarativeSlotPool

Parameters:

decrement - decrement by which to decrease the resource requirements

setResourceRequirements

public void setResourceRequirements(ResourceCounter resourceRequirements)

Description copied from interface: DeclarativeSlotPool

Sets the resource requirements to the given resourceRequirements.

Specified by:

setResourceRequirements in interface DeclarativeSlotPool

Parameters:

resourceRequirements - new resource requirements

getResourceRequirements

public Collection<ResourceRequirement> getResourceRequirements()

Description copied from interface: DeclarativeSlotPool

Returns the current resource requirements.

Specified by:

getResourceRequirements in interface DeclarativeSlotPool

Returns:

current resource requirements

offerSlots

public Collection<SlotOffer> offerSlots(Collection<? extends SlotOffer> offers,
                                        TaskManagerLocation taskManagerLocation,
                                        TaskManagerGateway taskManagerGateway,
                                        long currentTime)

Description copied from interface: DeclarativeSlotPool

Offers slots to this slot pool. The slot pool is free to accept as many slots as it needs.

Specified by:

offerSlots in interface DeclarativeSlotPool

Parameters:

offers - offers containing the list of slots offered to this slot pool

taskManagerLocation - taskManagerLocation is the location of the offering TaskExecutor

taskManagerGateway - taskManagerGateway is the gateway to talk to the offering TaskExecutor

currentTime - currentTime is the time the slots are being offered

Returns:

collection of accepted slots; the other slot offers are implicitly rejected

registerSlots

public Collection<SlotOffer> registerSlots(Collection<? extends SlotOffer> slots,
                                           TaskManagerLocation taskManagerLocation,
                                           TaskManagerGateway taskManagerGateway,
                                           long currentTime)

Description copied from interface: DeclarativeSlotPool

Registers the given set of slots at the slot pool. The slot pool will try to accept all slots unless the slot is unavailable (for example, the TaskManger is blocked).

The difference from DeclarativeSlotPool.offerSlots(java.util.Collection<? extends org.apache.flink.runtime.taskexecutor.slot.SlotOffer>, org.apache.flink.runtime.taskmanager.TaskManagerLocation, org.apache.flink.runtime.jobmanager.slots.TaskManagerGateway, long) is that this method allows accepting slots which exceed the currently required, but the DeclarativeSlotPool.offerSlots(java.util.Collection<? extends org.apache.flink.runtime.taskexecutor.slot.SlotOffer>, org.apache.flink.runtime.taskmanager.TaskManagerLocation, org.apache.flink.runtime.jobmanager.slots.TaskManagerGateway, long) only accepts those slots that are currently required.

Specified by:

registerSlots in interface DeclarativeSlotPool

Parameters:

slots - slots to register

taskManagerLocation - taskManagerLocation is the location of the offering TaskExecutor

taskManagerGateway - taskManagerGateway is the gateway to talk to the offering TaskExecutor

currentTime - currentTime is the time the slots are being offered

Returns:

the successfully registered slots; the other slot offers are implicitly rejected

reserveFreeSlot

public PhysicalSlot reserveFreeSlot(AllocationID allocationId,
                                    ResourceProfile requiredSlotProfile)

Description copied from interface: DeclarativeSlotPool

Reserves the free slot identified by the given allocationId and maps it to the given requiredSlotProfile.

Specified by:

reserveFreeSlot in interface DeclarativeSlotPool

Parameters:

allocationId - allocationId identifies the free slot to allocate

requiredSlotProfile - requiredSlotProfile specifying the resource requirement

Returns:

a PhysicalSlot representing the allocated slot

freeReservedSlot

public ResourceCounter freeReservedSlot(AllocationID allocationId,
                                        @Nullable
                                        Throwable cause,
                                        long currentTime)

Description copied from interface: DeclarativeSlotPool

Frees the reserved slot identified by the given allocationId. If no slot with allocationId exists, then the call is ignored.

Whether the freed slot is returned to the owning TaskExecutor is implementation dependent.

Specified by:

freeReservedSlot in interface DeclarativeSlotPool

Parameters:

allocationId - allocationId identifying the slot to release

cause - cause for releasing the slot; can be null

currentTime - currentTime when the slot was released

Returns:

the resource requirements that the slot was fulfilling

registerNewSlotsListener

public void registerNewSlotsListener(DeclarativeSlotPool.NewSlotsListener newSlotsListener)

Description copied from interface: DeclarativeSlotPool

Registers a listener which is called whenever new slots become available.

Specified by:

registerNewSlotsListener in interface DeclarativeSlotPool

Parameters:

newSlotsListener - which is called whenever new slots become available

releaseSlots

public ResourceCounter releaseSlots(ResourceID owner,
                                    Exception cause)

Description copied from interface: DeclarativeSlotPool

Releases all slots belonging to the owning TaskExecutor if it has been registered.

Specified by:

releaseSlots in interface DeclarativeSlotPool

Parameters:

owner - owner identifying the owning TaskExecutor

cause - cause for failing the slots

Returns:

the resource requirements that all slots were fulfilling; empty if all slots were currently free

releaseSlot

public ResourceCounter releaseSlot(AllocationID allocationId,
                                   Exception cause)

Description copied from interface: DeclarativeSlotPool

Releases the slot specified by allocationId if one exists.

Specified by:

releaseSlot in interface DeclarativeSlotPool

Parameters:

allocationId - allocationId identifying the slot to fail

cause - cause for failing the slot

Returns:

the resource requirements that the slot was fulfilling; empty if the slot was currently free

releaseIdleSlots

public void releaseIdleSlots(long currentTimeMillis)

Description copied from interface: DeclarativeSlotPool

Releases slots which have exceeded the idle slot timeout and are no longer needed to fulfill the resource requirements.

Specified by:

releaseIdleSlots in interface DeclarativeSlotPool

Parameters:

currentTimeMillis - current time

getFreeSlotsInformation

public Collection<SlotInfoWithUtilization> getFreeSlotsInformation()

Description copied from interface: DeclarativeSlotPool

Returns the slot information for all free slots (slots which can be allocated from the slot pool).

Specified by:

getFreeSlotsInformation in interface DeclarativeSlotPool

Returns:

collection of free slot information

getAllSlotsInformation

public Collection<? extends SlotInfo> getAllSlotsInformation()

Description copied from interface: DeclarativeSlotPool

Returns the slot information for all slots (free and allocated slots).

Specified by:

getAllSlotsInformation in interface DeclarativeSlotPool

Returns:

collection of slot information

containsFreeSlot

public boolean containsFreeSlot(AllocationID allocationId)

Description copied from interface: DeclarativeSlotPool

Checks whether the slot pool contains a slot with the given AllocationID and if it is free.

Specified by:

containsFreeSlot in interface DeclarativeSlotPool

Parameters:

allocationId - allocationId specifies the slot to check for

Returns:

true if the slot pool contains a free slot registered under the given allocation id; otherwise false

containsSlots

public boolean containsSlots(ResourceID owner)

Description copied from interface: DeclarativeSlotPool

Returns whether the slot pool has a slot registered which is owned by the given TaskExecutor.

Specified by:

containsSlots in interface DeclarativeSlotPool

Parameters:

owner - owner identifying the TaskExecutor for which to check whether the slot pool has some slots registered

Returns:

true if the given TaskExecutor has a slot registered at the slot pool