Class UtilizationModelStochastic

java.lang.Object

org.cloudsimplus.utilizationmodels.UtilizationModelAbstract

org.cloudsimplus.utilizationmodels.UtilizationModelStochastic

All Implemented Interfaces:

UtilizationModel

public class UtilizationModelStochastic
extends UtilizationModelAbstract

Implements a model, according to which a Cloudlet generates random resource utilization every time frame, using a ContinuousDistribution.

The class may return different utilization values for the same requested time. For performance reasons, this behavior is dependent of the

invalid reference

#isHistoryEnabled()

and

invalid reference

#isAlwaysGenNewRandUtilization()

.

Since:

CloudSim Toolkit 2.0

Author:

Anton Beloglazov, Manoel Campos da Silva Filho

Nested Class Summary

Nested classes/interfaces inherited from interface org.cloudsimplus.utilizationmodels.UtilizationModel

UtilizationModel.Unit

Field Summary

Fields inherited from class org.cloudsimplus.utilizationmodels.UtilizationModelAbstract

ALMOST_ZERO

Fields inherited from interface org.cloudsimplus.utilizationmodels.UtilizationModel

NULL

Constructor Summary

Constructors

Constructor	Description
UtilizationModelStochastic()	Instantiates a stochastic utilization model that defines the resource utilization in percentage.
UtilizationModelStochastic(long seed)	Instantiates a stochastic utilization model that defines the resource utilization in percentage.
UtilizationModelStochastic(ContinuousDistribution prng)	Instantiates a stochastic utilization model based on a given Pseudo Random Number Generator (PRNG).
UtilizationModelStochastic(UtilizationModel.Unit unit)	Instantiates a stochastic utilization model where the resource utilization is defined in the given unit.
UtilizationModelStochastic(UtilizationModel.Unit unit, long seed)	Instantiates a stochastic utilization model where the resource utilization is defined in the given unit.
UtilizationModelStochastic(UtilizationModel.Unit unit, @NonNull ContinuousDistribution prng)	Instantiates a stochastic new utilization model based on a given Pseudo Random Number Generator (PRNG).

Method Summary

Modifier and Type	Method	Description
protected Double	getUtilizationHistory(double time)	Gets the utilization percentage for a given time from the internal historyMap.
protected double	getUtilizationInternal(double time)
void	loadHistory(String filename)	Load a utilization history from a file.
void	saveHistory(String filename)	Save the utilization history to a file.

Methods inherited from class org.cloudsimplus.utilizationmodels.UtilizationModelAbstract

getUtilization, getUtilization, setUnit, validateUtilizationField, validateUtilizationField

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.cloudsimplus.utilizationmodels.UtilizationModel

getSimulation, getUnit, isOverCapacityRequestAllowed, setOverCapacityRequestAllowed, setSimulation

Constructor Details

UtilizationModelStochastic

public UtilizationModelStochastic()

Instantiates a stochastic utilization model that defines the resource utilization in percentage. The resource utilization history is enabled by default.

See Also:

• UtilizationModelAbstract.setUnit(Unit)
• invalid reference

  #setHistoryEnabled(boolean)

• invalid reference

  #isAlwaysGenNewRandUtilization()

UtilizationModelStochastic

public UtilizationModelStochastic(UtilizationModel.Unit unit)

Instantiates a stochastic utilization model where the resource utilization is defined in the given unit. The resource utilization history is enabled by default.

Parameters:

unit - the UtilizationModel.Unit that determines how the resource is used (for instance, if the resource usage is defined in percentage of the Vm resource or in absolute values)

See Also:

• invalid reference

  #setHistoryEnabled(boolean)

• invalid reference

  #isAlwaysGenNewRandUtilization()

UtilizationModelStochastic

public UtilizationModelStochastic(UtilizationModel.Unit unit,
 long seed)

Instantiates a stochastic utilization model where the resource utilization is defined in the given unit. The resource utilization history is enabled by default.

Parameters:

unit - the UtilizationModel.Unit that determines how the resource is used (for instance, if the resource usage is defined in percentage of the Vm resource or in absolute values)

seed - the seed to initialize the random number generator.

See Also:

• invalid reference

  #setHistoryEnabled(boolean)

• invalid reference

  #isAlwaysGenNewRandUtilization()

UtilizationModelStochastic

public UtilizationModelStochastic(long seed)

Instantiates a stochastic utilization model that defines the resource utilization in percentage. The resource utilization history is enabled by default.

Parameters:

seed - the seed to initialize the random number generator.

See Also:

• invalid reference

  #setHistoryEnabled(boolean)

• invalid reference

  #isAlwaysGenNewRandUtilization()

UtilizationModelStochastic

public UtilizationModelStochastic(ContinuousDistribution prng)

Instantiates a stochastic utilization model based on a given Pseudo Random Number Generator (PRNG). It defines the resource utilization in percentage. The resource utilization history is enabled by default.

Parameters:

prng - the Pseudo Random Number Generator (PRNG) to generate utilization values

See Also:

• UtilizationModelAbstract.setUnit(Unit)
• invalid reference

  #setHistoryEnabled(boolean)

• invalid reference

  #isAlwaysGenNewRandUtilization()

UtilizationModelStochastic

public UtilizationModelStochastic(UtilizationModel.Unit unit,
 @NonNull
 @NonNull ContinuousDistribution prng)

Instantiates a stochastic new utilization model based on a given Pseudo Random Number Generator (PRNG). The resource utilization history is enabled by default.

Parameters:

unit - the UtilizationModel.Unit that determines how the resource is used (for instance, if the resource usage is defined in percentage of the Vm resource or in absolute values)

prng - the Pseudo Random Number Generator (PRNG) to generate utilization values

See Also:

• invalid reference

  #setHistoryEnabled(boolean)

• invalid reference

  #isAlwaysGenNewRandUtilization()

Method Details

getUtilizationInternal

protected double getUtilizationInternal(double time)

Specified by:

getUtilizationInternal in class UtilizationModelAbstract

Parameters:

time -

Returns:

See Also:

• Issue #197 for more details

getUtilizationHistory

protected Double getUtilizationHistory(double time)

Gets the utilization percentage for a given time from the internal historyMap.

Parameters:

time - the time to get the utilization history for

Returns:

the stored utilization percentage or null if it has never been generated a utilization value for the given time

saveHistory

public void saveHistory(String filename)

Save the utilization history to a file.

Parameters:

filename - the filename

Throws:

IOException - when the file cannot be accessed

loadHistory

public void loadHistory(String filename)

Load a utilization history from a file.

Parameters:

filename - the filename

Throws:

IOException - when the file cannot be accessed