CloudletScheduler 类

简介

CloudletScheduler 是一个核心组件，在云计算仿真环境中，它负责定义虚拟机（VM）如何调度和执行其Cloudlets（云任务）。

• 抽象类：CloudletScheduler 是一个抽象类，这意味着它不能直接实例化，而是需要通过子类来实现具体的功能。

• 调度策略：这个类代表了虚拟机用来运行其Cloudlets的调度策略。调度策略决定了Cloudlets如何在虚拟机上分配和执行，包括它们如何共享或分配CPU时间、处理元素（PE）等资源。

• 执行Cloudlets：任何扩展 CloudletScheduler 类的子类都必须实现执行Cloudlets的功能。这意味着子类需要提供具体的逻辑来管理Cloudlets的执行，包括开始、暂停、恢复和结束Cloudlets。

• Cloudlet管理接口：CloudletScheduler 类还实现了Cloudlet管理的接口。这可能包括添加、删除、更新和查询Cloudlets状态的方法，以及可能的其他管理功能。

• 每个VM的实例：每个虚拟机都需要有自己的 CloudletScheduler 实例。这是因为每个虚拟机可能有不同的资源和调度需求，因此需要独立的调度器来管理其Cloudlets。

CloudletScheduler 类是云计算仿真工具（如CloudSim）中的一个关键组件，它允许开发者模拟和研究不同的调度策略，以优化资源使用效率、减少任务执行时间、提高系统吞吐量等。通过扩展这个抽象类，开发者可以创建自定义的调度器，以适应特定的应用场景或研究目标。

其他的类如
CloudletSchedulerDynamicWorkload 链接
CloudletSchedulerSpaceShared链接
CloudletSchedulerTimeShared 链接
继承自它

类属性

之前的运行时间

	/** The previous time. */private double previousTime;

当前可用的计算频率列表

	/** The list of current mips share available for the VM using the scheduler.* It is provided by {@link CloudletScheduler#updateCloudletsProcessing(double, List)} method.* at every simulation step. */private List<Double> currentMipsShare;

获得可用的计算能力

	private double currentCapacity;

等待队列

	/** The list of cloudlet waiting to be executed on the VM. */protected List<? extends Cloudlet> cloudletWaitingList;

正在执行的任务

	/** The list of cloudlets being executed on the VM. */protected List<? extends Cloudlet> cloudletExecList;

暂停的任务

	/** The list of paused cloudlets. */protected List<? extends Cloudlet> cloudletPausedList;

已经完成的任务

	/** The list of finished cloudlets. */protected List<? extends Cloudlet> cloudletFinishedList;

失败的任务

	/** The list of failed cloudlets. */protected List<? extends Cloudlet> cloudletFailedList;

最近完成的任务

	/** Buffer list of the latest finished cloudlets. */protected List<Cloudlet> cloudletJustFinishedList;

类方法

初始化

	/*** Creates a new CloudletScheduler object. * A CloudletScheduler must be created before starting the actual simulation.* * @pre $none* @post $none*/public CloudletScheduler()

更新运行时间

	/*** Updates the processing of cloudlets running under management of this scheduler.* * @param currentTime current simulation time* @param mipsShare list with MIPS share of each Pe available to the scheduler* @return the predicted completion time of the earliest finishing cloudlet, * or 0 if there is no next events* @pre currentTime >= 0* @post $none*/public double updateCloudletsProcessing(double currentTime, List<Double> mipsShare)@Deprecatedpublic double updateVmProcessing(double currentTime, List<Double> mipsShare)

更新正在等待的任务

	/*** Update the cloudlets currently waiting to execute.* The default implementation (i.e., no-op) is suitable for time-shared scheduling.** @param currentTime current simulation time* @param info        info Any data you may need to implement the update logic*/protected void updateWaitingCloudlets(double currentTime, Object info)/*** Receives a cloudlet to be executed in the VM managed by this scheduler.* * @param cl the submitted cloudlet* @return expected finish time of this cloudlet, or 0 if it is in a waiting queue* @pre gl != null* @post $none*/public double cloudletSubmit(Cloudlet cl)

取消任务的执行

	/*** Cancels execution of a cloudlet.* * @param cloudletId ID of the cloudlet being canceled* @return the canceled cloudlet, $null if not found* @pre $none* @post $none*/public Cloudlet cloudletCancel(final int cloudletId) 

暂停一个任务的执行

	/*** Pauses execution of a cloudlet.* * @param cloudletId ID of the cloudlet being paused* @return $true if cloudlet paused, $false otherwise* @pre $none* @post $none*/public boolean cloudletPause(int cloudletId)

回复一个暂停的任务

	/*** Resumes execution of a paused cloudlet.* * @param clId ID of the cloudlet being resumed* @return expected finish time of the cloudlet, 0.0 if queued* @pre $none* @post $none*/public abstract double cloudletResume(int clId);

完成任务

	/*** Processes a finished cloudlet.* * @param cl finished cloudlet* @pre rgl != $null* @post $none*/public void cloudletFinish(Cloudlet cl)

得到当前任务的状态

	/*** Gets the status of a cloudlet.* * @param cloudletId ID of the cloudlet* @return status of the cloudlet, -1 if cloudlet not found* @pre $none* @post $none**/public Cloudlet.CloudletStatus getCloudletStatus(final int cloudletId)

检查是否有已经完成的任务

	/*** Informs if there is any cloudlet that finished to execute in the VM managed by this scheduler.* * @return $true if there is at least one finished cloudlet; $false otherwise* @pre $none* @post $none* //TODO the method name would be isThereFinishedCloudlets to be clearer*/public boolean isFinishedCloudlets() 

返回下一个完成的任务

	/*** Returns the next cloudlet in the finished list.* * @return a finished cloudlet or $null if the respective list is empty* @pre $none* @post $none*/public Cloudlet getNextFinishedCloudlet()

返回虚拟机中运行的任务

	/*** Returns the number of cloudlets running in the virtual machine.* * @return number of cloudlets running* @pre $none* @post $none*/public int runningCloudlets()

返回一个任务进行任务迁移

	/*** Returns one cloudlet to migrate to another vm.* * @return one running cloudlet* @pre $none* @post $none** @TODO: Remo Andreoli: No clue why it's removing the first element*/public Cloudlet migrateCloudlet() 

获得任务的预计完成时间

/*** Get the estimated completion time of a given cloudlet.** @param cl the cloudlet* @param time the time* @return the estimated finish time*/public double getEstimatedFinishTime(Cloudlet cl, double time) 

获得总CPU利用率

	/*** Gets total CPU utilization percentage of all cloudlets, according to CPU UtilizationModel of * each one.* * @param time the time to get the current CPU utilization* @return total utilization*/public double getTotalUtilizationOfCpu(double time)

获得当前的请求频率(分内核)

	/*** Gets the current requested mips.* * @return the current mips*/public List<Double> getCurrentRequestedMips()

获得总请求计算量

	/*** Gets the total of the current requested mips.* * @return the current mips*/public double getCurrentRequestedTotalMips()

获得当前总可用的计算能力

	/*** Gets the total current available mips for the Cloudlet.* * @param rcl the rcl* @param mipsShare the mips share* @return the total current mips* //TODO In fact, this method is returning different data depending* of the subclass. It is expected that the way the method use to compute* the resulting value can be different in every subclass,* but is not supposed that each subclass returns a complete different * result for the same method of the superclass.* In some class such as NetworkCloudletSpaceSharedScheduler (OLD CLASS),* the method returns the average MIPS for the available PEs,* in other classes such as {@link CloudletSchedulerDynamicWorkload} it returns* the MIPS' sum of all PEs.*/public abstract double getTotalCurrentAvailableMipsForCloudlet(Cloudlet rcl, List<Double> mipsShare);

获得当前总请求的计算能力

	/*** Gets the total current requested mips for a given cloudlet.* * @param cl the cloudlet* @param time the time* @return the total current requested mips for the given cloudlet*/public abstract double getTotalCurrentRequestedMipsForCloudlet(Cloudlet cl, double time);

获得当前分配给任务的计算能力

	/*** Gets the total current allocated mips for cloudlet.* * @param cl the cloudlet* @param time the time* @return the total current allocated mips for cloudlet*/public abstract double getTotalCurrentAllocatedMipsForCloudlet(Cloudlet cl, double time);

当前请求的内存

	/*** Gets the current requested ram.* * @return the current requested ram*/public double getCurrentRequestedUtilizationOfRam() 

获得当前请求的带宽

	/*** Gets the current requested bw.* * @return the current requested bw*/public double getCurrentRequestedUtilizationOfBw() 

获得之前的运行时间

	/*** Gets the previous time.* * @return the previous time*/public double getPreviousTime()

设置之前的运行时间

	/*** Sets the previous time.* * @param previousTime the new previous time*/protected void setPreviousTime(double previousTime) 

设置计算资源的分配情况

	/*** Sets the current mips share.* * @param currentMipsShare the new current mips share*/protected void setCurrentMipsShare(List<Double> currentMipsShare)

获得可用的核心数

	/*** The number of PEs currently available for the VM using the scheduler,* according to the current mips share provided*/public int getCurrentPEs()

计算任务可用的计算量

	/** Get the individual MIPS capacity available for each cloudlet, according to the number of*  available PE provided by the current mip share.*/public double getCurrentCapacity()

更新任务可用的计算量

	/*** ASSUMPTION: all PEs have the same capacity.* @return capacity*/public double updateCurrentCapacity()@Deprecatedprotected double getCapacity(List<Double> mipsShare)

得到等待的任务队列

	/*** Gets the cloudlet waiting list.* * @param <T> the generic type* @return the cloudlet waiting list*/@SuppressWarnings("unchecked")public <T extends Cloudlet> List<T> getCloudletWaitingList()

设置任务等待队列

	/*** Cloudlet waiting list.* * @param <T> the generic type* @param cloudletWaitingList the cloudlet waiting list*/protected <T extends Cloudlet> void setCloudletWaitingList(List<T> cloudletWaitingList)

得到任务执行队列

	/*** Gets the cloudlet exec list.* * @param <T> the generic type* @return the cloudlet exec list*/@SuppressWarnings("unchecked")public <T extends Cloudlet> List<T> getCloudletExecList()

设置任务执行队列

	/*** Sets the cloudlet exec list.* * @param <T> the generic type* @param cloudletExecList the new cloudlet exec list*/protected <T extends Cloudlet> void setCloudletExecList(List<T> cloudletExecList)

得到任务暂停队列

	/*** Gets the cloudlet paused list.* * @param <T> the generic type* @return the cloudlet paused list*/@SuppressWarnings("unchecked")public <T extends Cloudlet> List<T> getCloudletPausedList()

设置任务暂停队列

	/*** Sets the cloudlet paused list.* * @param <T> the generic type* @param cloudletPausedList the new cloudlet paused list*/protected <T extends Cloudlet> void setCloudletPausedList(List<T> cloudletPausedList)

得到任务完成队列

	/*** Gets the cloudlet finished list.* * @param <T> the generic type* @return the cloudlet finished list*/@SuppressWarnings("unchecked")public <T extends Cloudlet> List<T> getCloudletFinishedList()

设置任务完成队列

	/*** Sets the cloudlet finished list.* * @param <T> the generic type* @param cloudletFinishedList the new cloudlet finished list*/protected <T extends Cloudlet> void setCloudletFinishedList(List<T> cloudletFinishedList)

得到任务失败队列

	/*** Gets the cloudlet failed list.* * @param <T> the generic type* @return the cloudlet failed list.*/@SuppressWarnings("unchecked")public <T extends Cloudlet> List<T>  getCloudletFailedList()

设置任务失败队列

	/*** Sets the cloudlet failed list.* * @param <T> the generic type* @param cloudletFailedList the new cloudlet failed list.*/protected <T extends Cloudlet> void setCloudletFailedList(List<T> cloudletFailedList)