Package org.cloudsimplus.autoscaling

Class HorizontalVmScalingSimple

java.lang.Object

org.cloudsimplus.autoscaling.VmScalingAbstract

org.cloudsimplus.autoscaling.HorizontalVmScalingSimple

All Implemented Interfaces:

HorizontalVmScaling, VmScaling

public class HorizontalVmScalingSimple
extends VmScalingAbstract
implements HorizontalVmScaling

A HorizontalVmScaling implementation that allows defining the condition to identify an overloaded VM, based on any desired criteria, such as current RAM, CPU and/or Bandwidth utilization. A DatacenterBroker monitors the VMs that have an HorizontalVmScaling object in order to create or destroy VMs on demand.

The overload condition has to be defined by providing a Predicate using the setOverloadPredicate(Predicate) method. Check the HorizontalVmScaling documentation for details on how to enable horizontal down scaling using the DatacenterBroker.

Since:

CloudSim Plus 1.0

Author:

Manoel Campos da Silva Filho

See Also:

HorizontalVmScaling

Field Summary

Fields inherited from interface org.cloudsimplus.autoscaling.HorizontalVmScaling

FALSE_PREDICATE, NULL

Fields inherited from interface org.cloudsimplus.autoscaling.VmScaling

NULL

Constructor Summary

Constructors

Constructor	Description
HorizontalVmScalingSimple()

Method Summary

Modifier and Type	Method	Description
Predicate<Vm>	getOverloadPredicate()	Gets a Predicate that defines when Vm is overloaded or not, that will make the Vm's DatacenterBroker to up scale the VM.
Supplier<Vm>	getVmSupplier()	Gets a Supplier that will be used to create VMs when the Load Balancer detects that the current Broker's VMs are overloaded.
protected boolean	requestUpScaling(double time)	Performs the actual request to scale the Vm up or down, depending if it is over or underloaded, respectively.
boolean	requestUpScalingIfPredicateMatches(VmHostEventInfo evt)	Requests a horizontal scale if the Vm is overloaded, according to the HorizontalVmScaling.getOverloadPredicate() predicate.
VmScaling	setOverloadPredicate(Predicate<Vm> predicate)	Sets a Predicate that defines when the Vm is overloaded or not, making the DatacenterBroker to up scale the VM.
HorizontalVmScaling	setVmSupplier(Supplier<Vm> supplier)	Sets a Supplier that will be used to create VMs when the Load Balancer detects that Broker's VMs are overloaded.

Methods inherited from class org.cloudsimplus.autoscaling.VmScalingAbstract

getVm, isTimeToCheckPredicate, setLastProcessingTime, setVm

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.cloudsimplus.autoscaling.VmScaling

getVm, setVm

Constructor Details

HorizontalVmScalingSimple

public HorizontalVmScalingSimple()

Method Details

getVmSupplier

public Supplier<Vm> getVmSupplier()

Description copied from interface: HorizontalVmScaling

Gets a Supplier that will be used to create VMs when the Load Balancer detects that the current Broker's VMs are overloaded.

Specified by:

getVmSupplier in interface HorizontalVmScaling

Returns:

setVmSupplier

public final HorizontalVmScaling setVmSupplier(Supplier<Vm> supplier)

Description copied from interface: HorizontalVmScaling

Sets a Supplier that will be used to create VMs when the Load Balancer detects that Broker's VMs are overloaded.

Specified by:

setVmSupplier in interface HorizontalVmScaling

Parameters:

supplier - the supplier to set

Returns:

getOverloadPredicate

public Predicate<Vm> getOverloadPredicate()

Description copied from interface: HorizontalVmScaling

Gets a Predicate that defines when Vm is overloaded or not, that will make the Vm's DatacenterBroker to up scale the VM. The up scaling is performed by creating new VMs to attend new arrived Cloudlets and then balance the load.

Specified by:

getOverloadPredicate in interface HorizontalVmScaling

Returns:

See Also:

HorizontalVmScaling.setOverloadPredicate(Predicate)

setOverloadPredicate

public VmScaling setOverloadPredicate(Predicate<Vm> predicate)

Description copied from interface: HorizontalVmScaling

Sets a Predicate that defines when the Vm is overloaded or not, making the DatacenterBroker to up scale the VM. The up scaling is performed by creating new VMs to attend new arrived Cloudlets in order to balance the load.

Specified by:

setOverloadPredicate in interface HorizontalVmScaling

Parameters:

predicate - a predicate that checks certain conditions to define a Vm as overloaded. The predicate receives the Vm that has to be checked. Such a condition can be defined, for instance, based on Vm's Vm.getCpuPercentUtilization(double) CPU usage} and/or any other VM resource usage. Despite the VmScaling already is already linked to a Vm, the Vm parameter for the Predicate enables reusing the same predicate to detect overload of different VMs.

Returns:

requestUpScaling

protected boolean requestUpScaling(double time)

Description copied from class: VmScalingAbstract

Performs the actual request to scale the Vm up or down, depending if it is over or underloaded, respectively. This method is automatically called by VmScaling.requestUpScalingIfPredicateMatches(org.cloudsimplus.listeners.VmHostEventInfo) when it is verified that the Vm is over or underloaded.

Specified by:

requestUpScaling in class VmScalingAbstract

Parameters:

time - current simulation time

Returns:

true if the request was actually sent, false otherwise

requestUpScalingIfPredicateMatches

public final boolean requestUpScalingIfPredicateMatches(VmHostEventInfo evt)

Description copied from interface: HorizontalVmScaling

Requests a horizontal scale if the Vm is overloaded, according to the HorizontalVmScaling.getOverloadPredicate() predicate. The scaling is performed by creating a new Vm using the HorizontalVmScaling.getVmSupplier() method and submitting it to the broker.

The time interval in which it will be checked if the Vm is overloaded depends on the Datacenter.getSchedulingInterval() value. Make sure to set such a value to enable the periodic overload verification.

The method will check the need to create a new VM at the time interval defined by the Datacenter.getSchedulingInterval(). A VM creation request is only sent when the VM is overloaded and new Cloudlets were submitted to the broker.

Specified by:

requestUpScalingIfPredicateMatches in interface HorizontalVmScaling

Specified by:

requestUpScalingIfPredicateMatches in interface VmScaling

Parameters:

evt - current simulation time

Returns:

true if the Vm is over or underloaded and up or down scaling request was sent to the broker, false otherwise