Package org.cloudbus.cloudsim.allocationpolicies

Class VmAllocationPolicyRandom

java.lang.Object

org.cloudbus.cloudsim.allocationpolicies.VmAllocationPolicyAbstract

org.cloudbus.cloudsim.allocationpolicies.VmAllocationPolicyRandom

All Implemented Interfaces:

VmAllocationPolicy

public class VmAllocationPolicyRandom
extends VmAllocationPolicyAbstract
implements VmAllocationPolicy

A VM allocation policy which finds a random Host having suitable resources to place a given VM. This is a high time-efficient policy with a best-case complexity O(1) and a worst-case complexity O(N), where N is the number of Hosts.

NOTES:

• This policy doesn't perform optimization of VM allocation by means of VM migration.
• It has a low computational complexity (high time-efficient) but may return and inactive Host that will be activated, while there may be active Hosts suitable for the VM.
• Despite the low computational complexity, such a policy may increase the number of active Hosts, that increases power consumption.

Since:

CloudSim Plus 4.4.2

Author:

Manoel Campos da Silva Filho

Field Summary

Fields inherited from interface org.cloudbus.cloudsim.allocationpolicies.VmAllocationPolicy

DEF_HOST_COUNT_PARALLEL_SEARCH, LOGGER, NULL

Constructor Summary

Constructors

Constructor	Description
VmAllocationPolicyRandom(ContinuousDistribution random)	Instantiates a VmAllocationPolicyRandom.

Method Summary

Modifier and Type	Method	Description
protected Optional<Host>	defaultFindHostForVm(Vm vm)	Provides the default implementation of the policy to find a suitable Host for a given VM.

Methods inherited from class org.cloudbus.cloudsim.allocationpolicies.VmAllocationPolicyAbstract

allocateHostForVm, allocateHostForVm, allocateHostForVm, deallocateHostForVm, findHostForVm, getDatacenter, getHostCountForParallelSearch, getHostList, getOptimizedAllocationMap, isVmMigrationSupported, scaleVmVertically, setDatacenter, setFindHostForVmFunction, setHostCountForParallelSearch

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.cloudbus.cloudsim.allocationpolicies.VmAllocationPolicy

allocateHostForVm, allocateHostForVm, allocateHostForVm, deallocateHostForVm, findHostForVm, getDatacenter, getHostCountForParallelSearch, getHostList, getOptimizedAllocationMap, isParallelHostSearchEnabled, isVmMigrationSupported, scaleVmVertically, setDatacenter, setFindHostForVmFunction, setHostCountForParallelSearch

Constructor Details

VmAllocationPolicyRandom

public VmAllocationPolicyRandom(ContinuousDistribution random)

Instantiates a VmAllocationPolicyRandom.

Parameters:

random - a Pseudo-Random Number Generator (PRNG) used to select a Host. The PRNG must return values between 0 and 1.

Method Details

defaultFindHostForVm

protected Optional<Host> defaultFindHostForVm(Vm vm)

Description copied from class: VmAllocationPolicyAbstract

Provides the default implementation of the policy to find a suitable Host for a given VM.

Specified by:

defaultFindHostForVm in class VmAllocationPolicyAbstract

Parameters:

vm - the VM to find a suitable Host to

Returns:

an Optional containing a suitable Host to place the VM or an empty Optional if no suitable Host was found

See Also:

• VmAllocationPolicyAbstract.setFindHostForVmFunction(BiFunction)