Updated the power models and added tests (#222)

* Updated the power models and added tests

* Updated test topologies

2 files changed, 106 insertions, 8 deletions

diff --git a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/power/CpuPowerModels.java b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/power/CpuPowerModels.java
index 7ba9eaed..537fb8d8 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/power/CpuPowerModels.java
+++ b/opendc-simulator/opendc-simulator-compute/src/main/java/org/opendc/simulator/compute/power/CpuPowerModels.java
@@ -163,6 +163,12 @@ public class CpuPowerModels {
             this.idlePower = idlePower;
         }
 
+        // Clamps the provided utilization in the range of 0.0 and 1.0
+        // This is done to avoid floating point errors
+        public double clampUtilization(double utilization) {
+            return Math.max(0.0, Math.min(1.0, utilization));
+        }
+
         @Override
         public String toString() {
             return getClass().getSimpleName() + "[max=" + maxPower + ",idle=" + idlePower + "]";
@@ -174,12 +180,14 @@ public class CpuPowerModels {
 
         SqrtPowerModel(double maxPower, double idlePower) {
             super(maxPower, idlePower);
-            this.factor = (maxPower - idlePower) / Math.sqrt(100);
+            this.factor = (maxPower - idlePower);
         }
 
         @Override
         public double computePower(double utilization) {
-            return idlePower + factor * Math.sqrt(utilization * 100);
+            utilization = clampUtilization(utilization);
+
+            return idlePower + factor * Math.sqrt(utilization);
         }
 
         @Override
@@ -198,12 +206,14 @@ public class CpuPowerModels {
 
         LinearPowerModel(double maxPower, double idlePower) {
             super(maxPower, idlePower);
-            this.factor = (maxPower - idlePower) / 100;
+            this.factor = maxPower - idlePower;
         }
 
         @Override
         public double computePower(double utilization) {
-            return idlePower + factor * utilization * 100;
+            utilization = clampUtilization(utilization);
+
+            return idlePower + factor * utilization;
         }
 
         @Override
@@ -222,12 +232,14 @@ public class CpuPowerModels {
 
         SquarePowerModel(double maxPower, double idlePower) {
             super(maxPower, idlePower);
-            this.factor = (maxPower - idlePower) / Math.pow(100, 2);
+            this.factor = (maxPower - idlePower);
         }
 
         @Override
         public double computePower(double utilization) {
-            return idlePower + factor * Math.pow(utilization * 100, 2);
+            utilization = clampUtilization(utilization);
+
+            return idlePower + factor * Math.pow(utilization, 2);
         }
 
         @Override
@@ -246,12 +258,14 @@ public class CpuPowerModels {
 
         CubicPowerModel(double maxPower, double idlePower) {
             super(maxPower, idlePower);
-            this.factor = (maxPower - idlePower) / Math.pow(100, 3);
+            this.factor = (maxPower - idlePower);
         }
 
         @Override
         public double computePower(double utilization) {
-            return idlePower + factor * Math.pow(utilization * 100, 3);
+            utilization = clampUtilization(utilization);
+
+            return idlePower + factor * Math.pow(utilization, 3);
         }
 
         @Override
diff --git a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PowerModelTest.kt b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PowerModelTest.kt
index e85758ae..e3bea821 100644
--- a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PowerModelTest.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PowerModelTest.kt
@@ -78,6 +78,90 @@ internal class PowerModelTest {
         )
     }
 
+    @Test
+    fun `test linear model`() {
+        val powerModel = CpuPowerModels.linear(400.0, 200.0)
+
+        assertAll(
+            { assertEquals(200.0, powerModel.computePower(-0.1)) },
+            { assertEquals(200.0, powerModel.computePower(0.0)) },
+            { assertEquals(220.0, powerModel.computePower(0.1)) },
+            { assertEquals(240.0, powerModel.computePower(0.2)) },
+            { assertEquals(260.0, powerModel.computePower(0.3)) },
+            { assertEquals(280.0, powerModel.computePower(0.4)) },
+            { assertEquals(300.0, powerModel.computePower(0.5)) },
+            { assertEquals(320.0, powerModel.computePower(0.6)) },
+            { assertEquals(340.0, powerModel.computePower(0.7)) },
+            { assertEquals(360.0, powerModel.computePower(0.8)) },
+            { assertEquals(380.0, powerModel.computePower(0.9)) },
+            { assertEquals(400.0, powerModel.computePower(1.0)) },
+            { assertEquals(400.0, powerModel.computePower(1.1)) },
+        )
+    }
+
+    @Test
+    fun `test sqrt model`() {
+        val powerModel = CpuPowerModels.sqrt(400.0, 200.0)
+
+        assertAll(
+            { assertEquals(200.0, powerModel.computePower(-1.0), 1.0) },
+            { assertEquals(200.0, powerModel.computePower(0.0), 1.0) },
+            { assertEquals(263.0, powerModel.computePower(0.1), 1.0) },
+            { assertEquals(289.0, powerModel.computePower(0.2), 1.0) },
+            { assertEquals(309.0, powerModel.computePower(0.3), 1.0) },
+            { assertEquals(326.0, powerModel.computePower(0.4), 1.0) },
+            { assertEquals(341.0, powerModel.computePower(0.5), 1.0) },
+            { assertEquals(354.0, powerModel.computePower(0.6), 1.0) },
+            { assertEquals(367.0, powerModel.computePower(0.7), 1.0) },
+            { assertEquals(378.0, powerModel.computePower(0.8), 1.0) },
+            { assertEquals(389.0, powerModel.computePower(0.9), 1.0) },
+            { assertEquals(400.0, powerModel.computePower(1.0), 1.0) },
+            { assertEquals(400.0, powerModel.computePower(1.1), 1.0) },
+        )
+    }
+
+    @Test
+    fun `test square model`() {
+        val powerModel = CpuPowerModels.square(400.0, 200.0)
+
+        assertAll(
+            { assertEquals(200.0, powerModel.computePower(-1.0), 1.0) },
+            { assertEquals(200.0, powerModel.computePower(0.0), 1.0) },
+            { assertEquals(202.0, powerModel.computePower(0.1), 1.0) },
+            { assertEquals(208.0, powerModel.computePower(0.2), 1.0) },
+            { assertEquals(218.0, powerModel.computePower(0.3), 1.0) },
+            { assertEquals(232.0, powerModel.computePower(0.4), 1.0) },
+            { assertEquals(250.0, powerModel.computePower(0.5), 1.0) },
+            { assertEquals(272.0, powerModel.computePower(0.6), 1.0) },
+            { assertEquals(298.0, powerModel.computePower(0.7), 1.0) },
+            { assertEquals(328.0, powerModel.computePower(0.8), 1.0) },
+            { assertEquals(362.0, powerModel.computePower(0.9), 1.0) },
+            { assertEquals(400.0, powerModel.computePower(1.0), 1.0) },
+            { assertEquals(400.0, powerModel.computePower(1.1), 1.0) },
+        )
+    }
+
+    @Test
+    fun `test cubic model`() {
+        val powerModel = CpuPowerModels.cubic(400.0, 200.0)
+
+        assertAll(
+            { assertEquals(200.0, powerModel.computePower(-1.0), 1.0) },
+            { assertEquals(200.0, powerModel.computePower(0.0), 1.0) },
+            { assertEquals(200.0, powerModel.computePower(0.1), 1.0) },
+            { assertEquals(201.0, powerModel.computePower(0.2), 1.0) },
+            { assertEquals(205.0, powerModel.computePower(0.3), 1.0) },
+            { assertEquals(212.0, powerModel.computePower(0.4), 1.0) },
+            { assertEquals(225.0, powerModel.computePower(0.5), 1.0) },
+            { assertEquals(243.0, powerModel.computePower(0.6), 1.0) },
+            { assertEquals(268.0, powerModel.computePower(0.7), 1.0) },
+            { assertEquals(302.0, powerModel.computePower(0.8), 1.0) },
+            { assertEquals(345.0, powerModel.computePower(0.9), 1.0) },
+            { assertEquals(400.0, powerModel.computePower(1.0), 1.0) },
+            { assertEquals(400.0, powerModel.computePower(1.1), 1.0) },
+        )
+    }
+
     @Suppress("unused")
     private companion object {
         @JvmStatic