org.cloudbus.cloudsim.datacenters

Interface Datacenter

All Superinterfaces:

Cloneable, Comparable<SimEntity>, Identifiable, Nameable, PowerAware, Runnable, SimEntity

All Known Implementing Classes:

DatacenterSimple, NetworkDatacenter

public interface Datacenter
extends SimEntity, PowerAware

An interface to be implemented by each class that provides Datacenter features. The interface implements the Null Object Design Pattern in order to start avoiding NullPointerException when using the NULL object instead of attributing null to Datacenter variables.

Since:

CloudSim Plus 1.0

Author:

Rodrigo N. Calheiros, Anton Beloglazov, Manoel Campos da Silva Filho

Nested Class Summary

Nested classes/interfaces inherited from interface org.cloudbus.cloudsim.core.SimEntity

SimEntity.State

Field Summary

Fields

Modifier and Type	Field and Description
static double	DEF_BW_PERCENT_FOR_MIGRATION The default percentage of bandwidth allocated for VM migration, is a value is not set.
static Datacenter	NULL A property that implements the Null Object Design Pattern for Datacenter objects.

Method Summary

Modifier and Type	Method and Description
<T extends Host> Datacenter	addHost(T host) Physically expands the Datacenter by adding a new Host (physical machine) to it.
<T extends Host> Datacenter	addHostList(List<T> hostList) Physically expands the Datacenter by adding a List of new Hosts (physical machines) to it.
Datacenter	addOnHostAvailableListener(EventListener<HostEventInfo> listener) Adds a EventListener object that will be notified every time when the a new Hosts is available for the Datacenter during simulation runtime.
long	getActiveHostsNumber() Gets the current number of Hosts that are powered on inside the Datacenter.
double	getBandwidthPercentForMigration() Gets the percentage of the bandwidth allocated to a Host to migrate VMs.
DatacenterCharacteristics	getCharacteristics() Gets the Datacenter characteristics.
DatacenterStorage	getDatacenterStorage() Gets the storage of the Datacenter.
Host	getHost(int index) Gets a Host in a given position inside the Host List.
Host	getHostById(long id) Gets a Host from its id.
<T extends Host> List<T>	getHostList() Gets an unmodifiable host list.
double	getPower() Gets an estimation of Datacenter power consumption in Watt-Second (Ws).
double	getSchedulingInterval() Gets the scheduling interval to process each event received by the Datacenter (in seconds).
VmAllocationPolicy	getVmAllocationPolicy() Gets the policy to be used by the Datacenter to allocate VMs into hosts.
<T extends Host> Datacenter	removeHost(T host) Removes a Host from its Datacenter.
void	setBandwidthPercentForMigration(double bandwidthPercentForMigration) Sets the percentage of the bandwidth allocated to a Host to migrate VMs.
void	setDatacenterStorage(DatacenterStorage datacenterStorage) Sets the storage of the Datacenter.
void	setPowerSupply(DatacenterPowerSupply powerSupply) Sets a DatacenterPowerSupply to enable computing the Datacenter's power consumption, based on the consumption of its Hosts.
Datacenter	setSchedulingInterval(double schedulingInterval) Sets the scheduling delay to process each event received by the Datacenter (in seconds).

Methods inherited from interface org.cloudbus.cloudsim.core.SimEntity

getSimulation, getState, isAlive, isFinished, isStarted, processEvent, run, schedule, schedule, schedule, schedule, schedule, setName, setSimulation, setState, shutdownEntity, start

Methods inherited from interface org.cloudbus.cloudsim.core.Nameable

getName

Methods inherited from interface org.cloudbus.cloudsim.core.Identifiable

getId

Methods inherited from interface java.lang.Comparable

compareTo

Methods inherited from interface org.cloudbus.cloudsim.power.models.PowerAware

getPowerInKWatts, wattsSecToKWattsHour

Field Detail

NULL

static final Datacenter NULL

A property that implements the Null Object Design Pattern for Datacenter objects.

DEF_BW_PERCENT_FOR_MIGRATION

static final double DEF_BW_PERCENT_FOR_MIGRATION

The default percentage of bandwidth allocated for VM migration, is a value is not set.

See Also:

setBandwidthPercentForMigration(double), Constant Field Values

Method Detail

getHostList

<T extends Host> List<T> getHostList()

Gets an unmodifiable host list.

Type Parameters:

T - The generic type

Returns:

the host list

getHost

Host getHost(int index)

Gets a Host in a given position inside the Host List.

Parameters:

index - the position of the List to get the Host

Returns:

getActiveHostsNumber

long getActiveHostsNumber()

Gets the current number of Hosts that are powered on inside the Datacenter.

Returns:

See Also:

Host.isActive()

getHostById

Host getHostById(long id)

Gets a Host from its id.

Parameters:

id - the ID of the Host to get from the List.

Returns:

the Host if found or Host.NULL otherwise

addHostList

<T extends Host> Datacenter addHostList(List<T> hostList)

Physically expands the Datacenter by adding a List of new Hosts (physical machines) to it. Hosts can be added before or after the simulation has started. If a Host is added during simulation execution, in case VMs are added dynamically too, they may be allocated to this new Host, depending on the VmAllocationPolicy.

If an ID is not assigned to a Host, the method assigns one.

Parameters:

hostList - the List of new hosts to be added

Returns:

See Also:

getVmAllocationPolicy()

addHost

<T extends Host> Datacenter addHost(T host)

Physically expands the Datacenter by adding a new Host (physical machine) to it. Hosts can be added before or after the simulation has started. If a Host is added during simulation execution, in case VMs are added dynamically too, they may be allocated to this new Host, depending on the VmAllocationPolicy.

If an ID is not assigned to the given Host, the method assigns one.

Parameters:

host - the new host to be added

Returns:

See Also:

getVmAllocationPolicy()

removeHost

<T extends Host> Datacenter removeHost(T host)

Removes a Host from its Datacenter.

Parameters:

host - the new host to be removed from its assigned Datacenter

Returns:

getVmAllocationPolicy

VmAllocationPolicy getVmAllocationPolicy()

Gets the policy to be used by the Datacenter to allocate VMs into hosts.

Returns:

the VM allocation policy

See Also:

VmAllocationPolicy

getSchedulingInterval

double getSchedulingInterval()

Gets the scheduling interval to process each event received by the Datacenter (in seconds). This value defines the interval in which processing of Cloudlets will be updated. The interval doesn't affect the processing of such cloudlets, it only defines in which interval the processing will be updated. For instance, if it is set a interval of 10 seconds, the processing of cloudlets will be updated at every 10 seconds. By this way, trying to get the amount of instructions the cloudlet has executed after 5 seconds, by means of Cloudlet.getFinishedLengthSoFar(Datacenter), it will not return an updated value. By this way, one should set the scheduling interval to 5 to get an updated result. As longer is the interval, faster will be the simulation execution.

Returns:

the scheduling interval (in seconds)

setSchedulingInterval

Datacenter setSchedulingInterval(double schedulingInterval)

Sets the scheduling delay to process each event received by the Datacenter (in seconds).

Parameters:

schedulingInterval - the new scheduling interval (in seconds)

Returns:

See Also:

getSchedulingInterval()

getCharacteristics

DatacenterCharacteristics getCharacteristics()

Gets the Datacenter characteristics.

Returns:

the Datacenter characteristics

getDatacenterStorage

DatacenterStorage getDatacenterStorage()

Gets the storage of the Datacenter.

Returns:

the storage

setDatacenterStorage

void setDatacenterStorage(DatacenterStorage datacenterStorage)

Sets the storage of the Datacenter.

Parameters:

datacenterStorage - the new storage

getBandwidthPercentForMigration

double getBandwidthPercentForMigration()

Gets the percentage of the bandwidth allocated to a Host to migrate VMs. It's a value between [0 and 1] (where 1 is 100%). The default value is 0.5, meaning only 50% of the bandwidth will be allowed for migration, while the remaining will be used for VM services.

Returns:

See Also:

DEF_BW_PERCENT_FOR_MIGRATION

setBandwidthPercentForMigration

void setBandwidthPercentForMigration(double bandwidthPercentForMigration)

Sets the percentage of the bandwidth allocated to a Host to migrate VMs. It's a value between [0 and 1] (where 1 is 100%). The default value is 0.5, meaning only 50% of the bandwidth will be allowed for migration, while the remaining will be used for VM services.

Parameters:

bandwidthPercentForMigration - the bandwidth migration percentage to set

getPower

double getPower()

Gets an estimation of Datacenter power consumption in Watt-Second (Ws).

To get actual power consumption, it's required to enable Host's StateHistory by calling Host.enableStateHistory() and use each Host PowerModel to compute power usage based on the CPU utilization got form the StateHistory.

Specified by:

getPower in interface PowerAware

Returns:

the estimated power consumption in Watt-Second (Ws)

See Also:

PowerAware.getPowerInKWatts()

addOnHostAvailableListener

Datacenter addOnHostAvailableListener(EventListener<HostEventInfo> listener)

Adds a EventListener object that will be notified every time when the a new Hosts is available for the Datacenter during simulation runtime. If the addHost(Host) or addHostList(List) is called before the simulation starts, the listeners will not be notified.

Parameters:

listener - the event listener to add

Returns:

setPowerSupply

void setPowerSupply(DatacenterPowerSupply powerSupply)

Sets a DatacenterPowerSupply to enable computing the Datacenter's power consumption, based on the consumption of its Hosts. Since this computation is expensive for large amount of Hosts and the researcher may not be interested in power consumption, the attribute is initialized with DatacenterPowerSupply.NULL. That avoids computing power consumption by default for every simulation, This way, the computation of power consumption must be explicitly enabled by the researcher by providing an instance to this attribute before the simulation starts.

Parameters:

powerSupply - a DatacenterPowerSupply instance to enable the Datacenter to compute its power consumption (if null is given, it disables such a computation)