Calculate the Waiting and Response time of a cloudlet

How to Calculate the Waiting and Response Time of a Cloudlet?

Condition for Calculate the Waiting and Response Time of a Cloudlet

Waiting Time:
It is the time a cloudlet spends in the queue before it starts execution. This can be calculated as the difference between the cloudlet's start time (execStartTime) and its submission time (submissionTime).
Response Time: This refers to the total time taken by the cloudlet from the moment it arrives in the system until its execution finishes. It includes the waiting time and the actual execution time. The response time can be calculated as the difference between the cloudlet's finish time (finishTime) and its submission time (submissionTime).

Sample Code

import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.LinkedList;
import java.util.List;
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 CloudletResponseAndWaitingTime {
/**
* The cloudlet list.
*/
private static List cloudletList;
/**
* The vmlist.
*/
private static List vmlist;
/**
* Creates main() to run this example
*/
public static void main(String[] args) {
Log.printLine("Starting CloudletResponseAndWaitingTime...");
try {
// 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
DatacenterBroker broker = createBroker();
int brokerId = broker.getId();
//Fourth step: Create one virtual machine
vmlist = new ArrayList();
//VM description
int vmid = 0;
int mips = 250;
long size = 10000; //image size (MB)
int ram = 2048; //vm memory (MB)
long bw = 1000;
int pesNumber = 1; //number of cpus
String vmm = "Xen"; //VMM name
//create two VMs
Vm vm1 = new Vm(vmid, brokerId, mips, pesNumber, ram, bw, size, vmm, new
CloudletSchedulerTimeShared());
//the second VM will have twice the priority of VM1 and so will receive twice CPU time
vmid++;
Vm vm2 = new Vm(vmid, brokerId, mips * 2, pesNumber, ram, bw, size, vmm, new
CloudletSchedulerTimeShared());
//add the VMs to the vmList
vmlist.add(vm1);
vmlist.add(vm2);
//submit vm list to the broker
broker.submitVmList(vmlist);
//Fifth step: Create two Cloudlets
cloudletList = new ArrayList();
//Cloudlet properties
int id = 0;
long length = 40000;
long fileSize = 300;
long outputSize = 300;
UtilizationModel utilizationModel = new UtilizationModelFull();
Cloudlet cloudlet1 = new Cloudlet(id, length, pesNumber, fileSize, outputSize,
utilizationModel, utilizationModel, utilizationModel);
cloudlet1.setUserId(brokerId);
id++;
Cloudlet cloudlet2 = new Cloudlet(id, length, pesNumber, fileSize, outputSize,
utilizationModel, utilizationModel, utilizationModel);
cloudlet2.setUserId(brokerId);
//add the cloudlets to the list
cloudletList.add(cloudlet1);
cloudletList.add(cloudlet2);
//submit cloudlet list to the broker
broker.submitCloudletList(cloudletList);
//bind the cloudlets to the vms. This way, the broker
// will submit the bound cloudlets only to the specific VM
broker.bindCloudletToVm(cloudlet1.getCloudletId(), vm1.getId());
broker.bindCloudletToVm(cloudlet2.getCloudletId(), vm2.getId());
// Sixth step: Starts the simulation
CloudSim.startSimulation();
// Final step: Print results when simulation is over
List newList = broker.getCloudletReceivedList();
CloudSim.stopSimulation();
printCloudletList(newList);
Log.printLine("CloudletResponseAndWaitingTime finished!");
} 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 hostList = new ArrayList();
// 2. A Machine contains one or more PEs or CPUs/Cores.
// In this example, it will have only one core.
List peList = new ArrayList();
int mips = 1000;
// 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 = 2048; //host memory (MB)
long storage = 1000000; //host storage
int bw = 10000;
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 peList2 = new ArrayList();
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 storageList = new LinkedList(); //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 list) {
int size = list.size();
Cloudlet cloudlet = null;
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");
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()));
}
}
double waitingTime = cloudlet.getExecStartTime() - cloudlet.getSubmissionTime();
// Calculate Response Time
double responseTime = cloudlet.getFinishTime() - cloudlet.getSubmissionTime();
Log.printLine("Cloudlet ID: " + cloudlet.getCloudletId());
Log.printLine("Waiting Time: " + waitingTime + " seconds");
Log.printLine("Response Time: " + responseTime + " seconds");
Log.printLine();
}
}