- Modified: energy for a time frame is calculated using linear interpolation

modules/cloudsim/src/main/java/org/cloudbus/cloudsim/HostDynamicWorkload.java

@@ -18,6 +18,7 @@ import org.cloudbus.cloudsim.lists.PeList;
 import org.cloudbus.cloudsim.provisioners.BwProvisioner;
 import org.cloudbus.cloudsim.provisioners.RamProvisioner;
 
+// TODO: Auto-generated Javadoc
 /**
  * The Class HostDynamicWorkload.
  *
@@ -28,6 +29,9 @@ public class HostDynamicWorkload extends Host {
 
 	/** The utilization mips. */
 	private double utilizationMips;
+	
+	/** The previous utilization mips. */
+	private double previousUtilizationMips;
 
 	/** The under allocated mips. */
 	private Map<String, List<List<Double>>> underAllocatedMips;
@@ -51,6 +55,7 @@ public class HostDynamicWorkload extends Host {
 			VmScheduler vmScheduler) {
 		super(id, ramProvisioner, bwProvisioner, storage, peList, vmScheduler);
 		setUtilizationMips(0);
+		setPreviousUtilizationMips(0);
 		setUnderAllocatedMips(new HashMap<String, List<List<Double>>>());
 		setVmsMigratingIn(new ArrayList<Vm>());
 	}
@@ -64,6 +69,7 @@ public class HostDynamicWorkload extends Host {
 			Log.printLine();
 		}
 		double smallerTime = super.updateVmsProcessing(currentTime);
+		setPreviousUtilizationMips(getUtilizationMips());
 		setUtilizationMips(0);
 
 		for (Vm vm : getVmList()) {
@@ -197,7 +203,7 @@ public class HostDynamicWorkload extends Host {
 	}
 
 	/**
-	 * Get current utilization of CPU in percents.
+	 * Get current utilization of CPU in percentage.
 	 *
 	 * @return current utilization of CPU in percents
 	 */
@@ -208,6 +214,19 @@ public class HostDynamicWorkload extends Host {
 		}
 		return utilization;
 	}
+	
+	/**
+	 * Gets the previous utilization of CPU in percentage.
+	 *
+	 * @return the previous utilization of cpu
+	 */
+	public double getPreviousUtilizationOfCpu() {
+		double utilization = getPreviousUtilizationMips() / getTotalMips();
+		if (utilization > 1 && utilization < 1.01) {
+			utilization = 1;
+		}
+		return utilization;
+	}
 
 	/**
 	 * Get current utilization of CPU in MIPS.
@@ -223,7 +242,7 @@ public class HostDynamicWorkload extends Host {
 	 *
 	 * @return the utilization mips
 	 */
-	protected double getUtilizationMips() {
+	public double getUtilizationMips() {
 		return utilizationMips;
 	}
 
@@ -234,6 +253,24 @@ public class HostDynamicWorkload extends Host {
 	 */
 	protected void setUtilizationMips(double utilizationMips) {
 		this.utilizationMips = utilizationMips;
+	}	
+
+	/**
+	 * Gets the previous utilization mips.
+	 *
+	 * @return the previous utilization mips
+	 */
+	public double getPreviousUtilizationMips() {
+		return previousUtilizationMips;
+	}
+	
+	/**
+	 * Sets the previous utilization mips.
+	 *
+	 * @param previousUtilizationMips the new previous utilization mips
+	 */
+	protected void setPreviousUtilizationMips(double previousUtilizationMips) {
+		this.previousUtilizationMips = previousUtilizationMips;
 	}
 
     /**

modules/cloudsim/src/main/java/org/cloudbus/cloudsim/power/PowerDatacenter.java

@@ -137,29 +137,21 @@ public class PowerDatacenter extends Datacenter {
 		double currentTime = CloudSim.clock();
 		double minTime = Double.MAX_VALUE;
 		double timeDiff = currentTime - getLastProcessTime();
-		double timeframePower = 0.0;
+		double timeFrameDatacenterEnergy = 0.0;
 
 		if (timeDiff > 0) {
 			Log.formatLine("\nEnergy consumption for the last time frame from %.2f to %.2f:", getLastProcessTime(), currentTime);
 
 			for (PowerHost host : this.<PowerHost>getHostList()) {
-				Log.printLine();
-				double hostPower = 0.0;
-
-				if (host.getUtilizationOfCpu() > 0) {
-					try {
-						hostPower = host.getPower() * timeDiff;
-						timeframePower += hostPower;
-					} catch (Exception e) {
-						e.printStackTrace();
-					}
-				}
+				double timeFrameHostEnergy = host.getEnergyLinearInterpolation(host.getPreviousUtilizationOfCpu(), host.getUtilizationOfCpu(), timeDiff);
+				timeFrameDatacenterEnergy += timeFrameHostEnergy;
 
+				Log.printLine();
 				Log.formatLine("%.2f: [Host #%d] utilization is %.2f%%", currentTime, host.getId(), host.getUtilizationOfCpu() * 100);
-				Log.formatLine("%.2f: [Host #%d] energy is %.2f W*sec", currentTime, host.getId(), hostPower);
+				Log.formatLine("%.2f: [Host #%d] energy is %.2f W*sec", currentTime, host.getId(), timeFrameHostEnergy);
 			}
 
-			Log.formatLine("\n%.2f: Consumed energy is %.2f W*sec\n", currentTime, timeframePower);
+			Log.formatLine("\n%.2f: Consumed energy is %.2f W*sec\n", currentTime, timeFrameDatacenterEnergy);
 		}
 
 		Log.printLine("\n\n--------------------------------------------------------------\n\n");
@@ -176,7 +168,7 @@ public class PowerDatacenter extends Datacenter {
 			Log.formatLine("%.2f: [Host #%d] utilization is %.2f%%", currentTime, host.getId(), host.getUtilizationOfCpu() * 100);
 		}
 
-		setPower(getPower() + timeframePower);
+		setPower(getPower() + timeFrameDatacenterEnergy);
 		
 		checkCloudletCompletion();
 		

modules/cloudsim/src/main/java/org/cloudbus/cloudsim/power/PowerHost.java

@@ -56,9 +56,19 @@ public class PowerHost extends HostDynamicWorkload {
 	 * @return the power
 	 */
 	public double getPower() {
+		return getPower(getUtilizationOfCpu());
+	}
+	
+	/**
+	 * Gets the power. For this moment only consumed by all PEs.
+	 *
+	 * @param utilization the utilization
+	 * @return the power
+	 */
+	protected double getPower(double utilization) {
 		double power = 0;
 		try {
-			power = getPowerModel().getPower(getUtilizationOfCpu());
+			power = getPowerModel().getPower(utilization);
 		} catch (Exception e) {
 			e.printStackTrace();
 			System.exit(0);
@@ -82,6 +92,20 @@ public class PowerHost extends HostDynamicWorkload {
 		return power;
 	}
 	
+	/**
+	 * Gets the energy consumption using linear interpolation of the utilization change.
+	 *
+	 * @param fromUtilization the from utilization
+	 * @param toUtilization the to utilization
+	 * @param time the time
+	 * @return the energy
+	 */
+	public double getEnergyLinearInterpolation(double fromUtilization, double toUtilization, double time) {
+		double fromPower = getPower(fromUtilization);
+		double toPower = getPower(toUtilization);
+		return (fromPower + (toPower - fromPower) / 2) * time;		
+	}
+	
 	/**
 	 * Sets the power model.
 	 *

modules/cloudsim/src/test/java/org/cloudbus/cloudsim/power/PowerHostTest.java

@@ -9,6 +9,7 @@
 package org.cloudbus.cloudsim.power;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -16,6 +17,7 @@ import java.util.List;
 import org.cloudbus.cloudsim.Pe;
 import org.cloudbus.cloudsim.power.models.PowerModelLinear;
 import org.cloudbus.cloudsim.provisioners.PeProvisionerSimple;
+import org.junit.Before;
 import org.junit.Test;
 
 /**
@@ -27,13 +29,33 @@ public class PowerHostTest {
 	private static final double MIPS = 1000;
 	private static final double MAX_POWER = 200;
 	private static final double STATIC_POWER_PERCENT = 0.3;
+	private static final double TIME = 10;
+	
+	private PowerHost host;
+	
+	@Before
+	public void setUp() throws Exception {
+		List<Pe> peList = new ArrayList<Pe>();
+		peList.add(new Pe(0, new PeProvisionerSimple(MIPS)));
+		host = new PowerHost(0, null, null, 0, peList, null, new PowerModelLinear(MAX_POWER, STATIC_POWER_PERCENT));
+	}
 
 	@Test
 	public void testGetMaxPower() {
-		List<Pe> peList = new ArrayList<Pe>();
-		peList.add(new Pe(0, new PeProvisionerSimple(MIPS)));
-		PowerHost host = new PowerHost(0, null, null, 0, peList, null, new PowerModelLinear(MAX_POWER, STATIC_POWER_PERCENT));
 		assertEquals(MAX_POWER, host.getMaxPower(), 0);		
 	}
+	
+	@Test
+	public void testGetEnergy() {
+		assertEquals(0, host.getEnergyLinearInterpolation(0, 0, TIME), 0);
+		double expectedEnergy = 0;
+		try {
+			expectedEnergy = (host.getPowerModel().getPower(0.2) + (host.getPowerModel().getPower(0.9) - host.getPowerModel().getPower(0.2)) / 2) * TIME;
+		} catch (Exception e) {
+			e.printStackTrace();
+			fail();
+		}
+		assertEquals(expectedEnergy, host.getEnergyLinearInterpolation(0.2, 0.9, TIME), 0);
+	}
 
 }