等待时间在cloudsim中未显示任何内容为什么？

Question

/*
 * Title:        CloudSim Toolkit
 * Description:  CloudSim (Cloud Simulation) Toolkit for Modeling and Simulation
 *               of Clouds
 * Licence:      GPL - http://www.gnu.org/copyleft/gpl.html
 *
 * Copyright (c) 2009, The University of Melbourne, Australia
 */

//package org.cloudbus.cloudsim.examples;

//package cloudIntro;

import java.text.DecimalFormat;
import java.util.*;
import java.util.concurrent.ThreadLocalRandom;

import org.cloudbus.cloudsim.Cloudlet;
import org.cloudbus.cloudsim.CloudletSchedulerTimeShared;
import org.cloudbus.cloudsim.Datacenter;
import org.cloudbus.cloudsim.DatacenterBroker;
import org.cloudbus.cloudsim.DatacenterCharacteristics;
import org.cloudbus.cloudsim.Host;
import org.cloudbus.cloudsim.Log;
import org.cloudbus.cloudsim.Pe;
import org.cloudbus.cloudsim.Storage;
import org.cloudbus.cloudsim.UtilizationModel;
import org.cloudbus.cloudsim.UtilizationModelFull;
import org.cloudbus.cloudsim.Vm;
import org.cloudbus.cloudsim.VmAllocationPolicySimple;
import org.cloudbus.cloudsim.VmSchedulerTimeShared;
import org.cloudbus.cloudsim.core.CloudSim;
import org.cloudbus.cloudsim.provisioners.BwProvisionerSimple;
import org.cloudbus.cloudsim.provisioners.PeProvisionerSimple;
import org.cloudbus.cloudsim.provisioners.RamProvisionerSimple;


/**
 * A simple example showing how to create
 * a datacenter with two hosts and run two
 * cloudlets on it. The cloudlets run in
 * VMs with different MIPS requirements.
 * The cloudlets will take different time
 * to complete the execution depending on
 * the requested VM performance.
 */
public class Simulation
{



    /**
     * Creates main() to run this example
     */
    public static void main(String[] args)
    {
        Log.printLine("Starting CloudSimExample3...");

        try
        {

            int noOfTypes = 6;
            // First step: Initialize the CloudSim package. It should be called
            // before creating any entities.
            int num_user = 1;   // number of cloud users
            Calendar calendar = Calendar.getInstance();
            boolean trace_flag = false;  // mean trace events

            // Initialize the CloudSim library
            CloudSim.init(num_user, calendar, trace_flag);

            // Second step: Create Datacenters
            //Datacenters are the resource providers in CloudSim. We need at list one of them to run a CloudSim simulation
            @SuppressWarnings("unused")
            Datacenter datacenter0 = createDatacenter("Datacenter_0");

            //Third step: Create Broker


            //Fourth step: Create one virtual machine


            //VM description
            int vmid = 0;
            int mips = 250;
            long size = 10000; //image size (MB)
            int ram = 512; //vm memory (MB)
            long bw = 1000;
            int pesNumber = 1; //number of cpus
            String vmm = "Xen"; //VMM name


            //Fifth step: Create two Cloudlets


            //Cloudlet properties
            int id = 0;
            long length = 40000;
            long fileSize = 300;
            long outputSize = 300;
            UtilizationModel utilizationModel = new UtilizationModelFull();

            int vmNumberArray[] = {1,1,1,1,1,1};
            int cloudletNumberArray[] = {500,500,500,500,500,500};

            ArrayList<DatacenterBroker> brokerList = new ArrayList<>();
            for(int i=0;i<noOfTypes;i++) // create 6 types of vm
            {
                List<Cloudlet> cloudletList = new ArrayList<>();
                List<Vm> vmlist = new ArrayList<>();
                DatacenterBroker broker = createBroker();
                brokerList.add(broker);
                int brokerId = broker.getId();
                //int randomNumber1 = ThreadLocalRandom.current().nextInt(1,15);
                int randomNumber1 = vmNumberArray[i];
                for(int j=0;j<randomNumber1;j++)
                {
                    Vm vm = new Vm(vmid, brokerId, mips, pesNumber, ram, bw, size, vmm, new CloudletSchedulerTimeShared());
                    vmid++;
                    vmlist.add(vm);
                }
                //int randomNumber2 = ThreadLocalRandom.current().nextInt(20,30);
                int randomNumber2 = cloudletNumberArray[i];
                for(int j=0;j<randomNumber2;j++)
                {
                    Cloudlet cloudlet = new Cloudlet(id, length, pesNumber, fileSize, outputSize, utilizationModel, utilizationModel, utilizationModel);
                    id++;
                    cloudlet.setUserId(brokerId);
                    cloudletList.add(cloudlet);
                }
                broker.submitVmList(vmlist);
                broker.submitCloudletList(cloudletList);
            }
            long start = System.nanoTime();
            CloudSim.startSimulation();
            for(int i=0;i<noOfTypes;i++)
            {
                List<Cloudlet> cloudletList = brokerList.get(i).getCloudletReceivedList();
                printCloudletList(cloudletList);
            }
            CloudSim.stopSimulation();
            long end = System.nanoTime();
            Log.printLine("CloudSim finished");
            System.out.println("total time required = "+(end-start));
        }
        catch (Exception e) {
            e.printStackTrace();
            Log.printLine("The simulation has been terminated due to an unexpected error");
        }
    }

    private static Datacenter createDatacenter(String name)
    {

        // Here are the steps needed to create a PowerDatacenter:
        // 1. We need to create a list to store
        //    our machine
        List<Host> hostList = new ArrayList<Host>();

        // 2. A Machine contains one or more PEs or CPUs/Cores.
        // In this example, it will have only one core.
        List<Pe> peList = new ArrayList<Pe>();

        int mips = 60000;

        // 3. Create PEs and add these into a list.
        peList.add(new Pe(0, new PeProvisionerSimple(mips))); // need to store Pe id and MIPS Rating

        //4. Create Hosts with its id and list of PEs and add them to the list of machines
        int hostId=0;
        int ram = 307230720; //host memory (MB)
        long storage = 1000000; //host storage
        int bw = 10000000;

        hostList.add(
                new Host(
                        hostId,
                        new RamProvisionerSimple(ram),
                        new BwProvisionerSimple(bw),
                        storage,
                        peList,
                        new VmSchedulerTimeShared(peList)
                )
        ); // This is our first machine

        //create another machine in the Data center
        /*List<Pe> peList2 = new ArrayList<Pe>();

        peList2.add(new Pe(0, new PeProvisionerSimple(mips)));

        hostId++;

        hostList.add(
                new Host(
                        hostId,
                        new RamProvisionerSimple(ram),
                        new BwProvisionerSimple(bw),
                        storage,
                        peList2,
                        new VmSchedulerTimeShared(peList2)
                )
        );*/ // This is our second machine



        // 5. Create a DatacenterCharacteristics object that stores the
        //    properties of a data center: architecture, OS, list of
        //    Machines, allocation policy: time- or space-shared, time zone
        //    and its price (G$/Pe time unit).
        String arch = "x86";      // system architecture
        String os = "Linux";          // operating system
        String vmm = "Xen";
        double time_zone = 10.0;         // time zone this resource located
        double cost = 3.0;              // the cost of using processing in this resource
        double costPerMem = 0.05;       // the cost of using memory in this resource
        double costPerStorage = 0.001;  // the cost of using storage in this resource
        double costPerBw = 0.0;         // the cost of using bw in this resource
        LinkedList<Storage> storageList = new LinkedList<Storage>();    //we are not adding SAN devices by now

        DatacenterCharacteristics characteristics = new DatacenterCharacteristics(
                arch, os, vmm, hostList, time_zone, cost, costPerMem, costPerStorage, costPerBw);

        // 6. Finally, we need to create a PowerDatacenter object.
        Datacenter datacenter = null;
        try {
            datacenter = new Datacenter(name, characteristics, new VmAllocationPolicySimple(hostList), storageList, 0);
        } catch (Exception e) {
            e.printStackTrace();
        }

        return datacenter;
    }

    //We strongly encourage users to develop their own broker policies, to submit vms and cloudlets according
    //to the specific rules of the simulated scenario
    private static DatacenterBroker createBroker()
    {

        DatacenterBroker broker = null;
        try
        {
            broker = new DatacenterBroker("Broker");
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        return broker;
    }

    /**
     * Prints the Cloudlet objects
     * @param list  list of Cloudlets
     */
    private static void printCloudletList(List<Cloudlet> list)
    {
        int size = list.size();
        Cloudlet cloudlet;

        String indent = "    ";
        Log.printLine();
        Log.printLine("========== OUTPUT ==========");
        Log.printLine("Cloudlet ID" + indent + "STATUS" + indent +
                "Data center ID" + indent + "VM ID" + indent + "Time" + indent + "Start Time" + indent + "Finish Time" + indent + "waiting Time");

        DecimalFormat dft = new DecimalFormat("###.##");
        for (int i = 0; i < size; i++)
        {
            cloudlet = list.get(i);
            Log.print(indent + cloudlet.getCloudletId() + indent + indent);

            if (cloudlet.getCloudletStatus() == Cloudlet.SUCCESS)
            {
                Log.print("SUCCESS");

                Log.printLine( indent + indent + cloudlet.getResourceId() + indent + indent + indent + cloudlet.getVmId() +
                        indent + indent + dft.format(cloudlet.getActualCPUTime()) + indent + indent + dft.format(cloudlet.getExecStartTime())+
                        indent + indent + dft.format(cloudlet.getFinishTime()) + dft.format(cloudlet.getWaitingTime()));
            }
        }

    }
}

此代码由cloudsim示例3代码修改而来https://github.com/Cloudslab/cloudsim/blob/master/modules/cloudsim-examples/src/main/java/org/cloudbus/cloudsim/examples/CloudSimExample3.java.

在这里，我创建了一个数据中心，其中包含一个主机和6个数据中心代理。每个代理都有一个VM和500个Cloud dlet。

输出文件https://paste.ubuntu.com/p/ZmmK2nFmyS/

输出显示，在brocker中，每个cloudlet在某个时间启动，等待时间不显示任何表示零（0）的内容。如果VM中有一个cpu，并且没有等待时间，那么如何在VM中一次启动500个任务？

Answer 1

这是因为您使用了CloudletSchedulerTimeShared，而不是CloudletSchedulerSpaceShared等其他实现。在实际操作系统中，如果CPU数量低于应用程序数量（通常情况下），即使是分时调度器也会让一些应用程序等待。

CloudSim提供了一个过于简化的时间共享调度程序。有一个答案可以解释如何在这里实现这样的调度器。