Package org.cloudbus.cloudsim.allocationpolicies

Class VmAllocationPolicyBestFit

java.lang.Object

org.cloudbus.cloudsim.allocationpolicies.VmAllocationPolicyAbstract

org.cloudbus.cloudsim.allocationpolicies.VmAllocationPolicyBestFit

All Implemented Interfaces:

VmAllocationPolicy

public class VmAllocationPolicyBestFit
extends VmAllocationPolicyAbstract

A Best Fit VmAllocationPolicy implementation that chooses, as the host for a VM, the one with the most number of PEs in use, which has enough free PEs for a VM.

This is a really computationally complex policy since the worst-case complexity to allocate a Host for a VM is O(N), where N is the number of Hosts. Such an implementation is not appropriate for large scale scenarios.

NOTE: This policy doesn't perform optimization of VM allocation by means of VM migration.

Since:

CloudSim Plus 3.0.1

Author:

Manoel Campos da Silva Filho

See Also:

• VmAllocationPolicyFirstFit
• VmAllocationPolicySimple

Field Summary

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

DEF_HOST_COUNT_PARALLEL_SEARCH, LOGGER, NULL

Constructor Summary

Constructors

Constructor	Description
VmAllocationPolicyBestFit()

Method Summary

Modifier and Type	Method	Description
protected Optional<Host>	defaultFindHostForVm(Vm vm)	Gets the first suitable host from the VmAllocationPolicyAbstract.getHostList() that has the highest number of PEs in use (i.e.

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

isParallelHostSearchEnabled

Constructor Details

VmAllocationPolicyBestFit

public VmAllocationPolicyBestFit()

Method Details

defaultFindHostForVm

protected Optional<Host> defaultFindHostForVm(Vm vm)

Gets the first suitable host from the VmAllocationPolicyAbstract.getHostList() that has the highest number of PEs in use (i.e. the least number of free PEs).

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 not found

See Also:

• VmAllocationPolicyAbstract.setFindHostForVmFunction(BiFunction)