simulator: Add Linux CPU frequency scaling governors

This change adds the CPU frequency scaling governors that are found in
the Linux kernel, which include the conservative and on-demand governor.

5 files changed, 265 insertions, 15 deletions

diff --git a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/ConservativeScalingGovernorTest.kt b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/ConservativeScalingGovernorTest.kt
new file mode 100644
index 00000000..59817f1d
--- /dev/null
+++ b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/ConservativeScalingGovernorTest.kt
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package org.opendc.simulator.compute.cpufreq
+
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+/**
+ * Test suite for the [ConservativeScalingGovernor]
+ */
+internal class ConservativeScalingGovernorTest {
+    @Test
+    fun testSetStartLimitWithoutPStates() {
+        val cpuCapacity = 4100.0
+        val minSpeed = cpuCapacity / 2
+        val defaultThreshold = 0.8
+        val defaultStepSize = 0.05 * cpuCapacity
+        val governor = ConservativeScalingGovernor()
+
+        val policy = mockk<ScalingPolicy>(relaxUnitFun = true)
+        every { policy.max } returns cpuCapacity
+        every { policy.min } returns minSpeed
+
+        var target = 0.0
+        every { policy.target } answers { target }
+        every { policy.target = any() } propertyType Double::class answers { target = value }
+
+        val logic = governor.createLogic(policy)
+        logic.onStart()
+        assertEquals(defaultThreshold, governor.threshold)
+
+        logic.onLimit(0.5)
+
+        /* Upwards scaling */
+        logic.onLimit(defaultThreshold + 0.2)
+
+        /* Downwards scaling */
+        logic.onLimit(defaultThreshold + 0.1)
+
+        verify(exactly = 2) { policy.target = minSpeed }
+        verify(exactly = 1) { policy.target = minSpeed + defaultStepSize }
+    }
+
+    @Test
+    fun testSetStartLimitWithPStatesAndParams() {
+        val firstPState = 1000.0
+        val cpuCapacity = 4100.0
+        val minSpeed = firstPState
+        val threshold = 0.5
+        val stepSize = 0.02 * cpuCapacity
+        val governor = ConservativeScalingGovernor(threshold, stepSize)
+
+        val policy = mockk<ScalingPolicy>(relaxUnitFun = true)
+        every { policy.max } returns cpuCapacity
+        every { policy.min } returns firstPState
+
+        var target = 0.0
+        every { policy.target } answers { target }
+        every { policy.target = any() } propertyType Double::class answers { target = value }
+
+        val logic = governor.createLogic(policy)
+        logic.onStart()
+        assertEquals(threshold, governor.threshold)
+        logic.onLimit(0.5)
+
+        /* Upwards scaling */
+        logic.onLimit(threshold + 0.2)
+
+        /* Downwards scaling */
+        logic.onLimit(threshold + 0.1)
+
+        verify(exactly = 2) { policy.target = minSpeed }
+        verify(exactly = 1) { policy.target = minSpeed + stepSize }
+    }
+}
diff --git a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/OnDemandScalingGovernorTest.kt b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/OnDemandScalingGovernorTest.kt
new file mode 100644
index 00000000..c0c25c97
--- /dev/null
+++ b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/OnDemandScalingGovernorTest.kt
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package org.opendc.simulator.compute.cpufreq
+
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+/**
+ * Test suite for the [OnDemandScalingGovernor]
+ */
+internal class OnDemandScalingGovernorTest {
+    @Test
+    fun testSetStartLimitWithoutPStates() {
+        val cpuCapacity = 4100.0
+        val minSpeed = cpuCapacity / 2
+        val defaultThreshold = 0.8
+        val governor = OnDemandScalingGovernor()
+
+        val policy = mockk<ScalingPolicy>(relaxUnitFun = true)
+        every { policy.min } returns minSpeed
+        every { policy.max } returns cpuCapacity
+
+        val logic = governor.createLogic(policy)
+        logic.onStart()
+        assertEquals(defaultThreshold, governor.threshold)
+        verify(exactly = 1) { policy.target = minSpeed }
+
+        logic.onLimit(0.5)
+        verify(exactly = 1) { policy.target = minSpeed + 0.5 * (cpuCapacity - minSpeed) / 100 }
+
+        logic.onLimit(defaultThreshold)
+        verify(exactly = 1) { policy.target = cpuCapacity }
+    }
+
+    @Test
+    fun testSetStartLimitWithPStatesAndParams() {
+        val firstPState = 1000.0
+        val cpuCapacity = 4100.0
+        val threshold = 0.5
+        val governor = OnDemandScalingGovernor(threshold)
+
+        val policy = mockk<ScalingPolicy>(relaxUnitFun = true)
+        every { policy.max } returns cpuCapacity
+        every { policy.min } returns firstPState
+
+        val logic = governor.createLogic(policy)
+
+        logic.onStart()
+        assertEquals(threshold, governor.threshold)
+        verify(exactly = 1) { policy.target = firstPState }
+
+        logic.onLimit(0.1)
+        verify(exactly = 1) { policy.target = firstPState + 0.1 * (cpuCapacity - firstPState) / 100 }
+
+        logic.onLimit(threshold)
+        verify(exactly = 1) { policy.target = cpuCapacity }
+    }
+}
diff --git a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/PerformanceScalingGovernorTest.kt b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/PerformanceScalingGovernorTest.kt
index 8e8b09c8..d7bd6193 100644
--- a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/PerformanceScalingGovernorTest.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/PerformanceScalingGovernorTest.kt
@@ -23,10 +23,9 @@
 package org.opendc.simulator.compute.cpufreq
 
 import io.mockk.every
-import io.mockk.mockk
+import io.mockk.spyk
 import io.mockk.verify
 import org.junit.jupiter.api.Test
-import org.opendc.simulator.compute.SimProcessingUnit
 
 /**
  * Test suite for the [PerformanceScalingGovernor]
@@ -34,16 +33,18 @@ import org.opendc.simulator.compute.SimProcessingUnit
 internal class PerformanceScalingGovernorTest {
     @Test
     fun testSetStartLimit() {
-        val cpu = mockk<SimProcessingUnit>(relaxUnitFun = true)
+        val policy = spyk<ScalingPolicy>()
+        val logic = PerformanceScalingGovernor().createLogic(policy)
 
-        every { cpu.model.frequency } returns 4100.0
-        every { cpu.speed } returns 2100.0
-
-        val logic = PerformanceScalingGovernor().createLogic(cpu)
+        every { policy.max } returns 4100.0
 
         logic.onStart()
-        logic.onLimit(1.0)
+        verify(exactly = 1) { policy.target = 4100.0 }
 
-        verify(exactly = 1) { cpu.capacity = 4100.0 }
+        logic.onLimit(0.0)
+        verify(exactly = 1) { policy.target = 4100.0 }
+
+        logic.onLimit(1.0)
+        verify(exactly = 1) { policy.target = 4100.0 }
     }
 }
diff --git a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/PowerSaveScalingGovernorTest.kt b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/PowerSaveScalingGovernorTest.kt
new file mode 100644
index 00000000..8d841981
--- /dev/null
+++ b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/cpufreq/PowerSaveScalingGovernorTest.kt
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package org.opendc.simulator.compute.cpufreq
+
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.jupiter.api.Test
+
+/**
+ * Test suite for the [PowerSaveScalingGovernor]
+ */
+internal class PowerSaveScalingGovernorTest {
+    @Test
+    fun testSetStartLimitWithoutPStates() {
+        val cpuCapacity = 4100.0
+        val minSpeed = cpuCapacity / 2
+        val policy = mockk<ScalingPolicy>(relaxUnitFun = true)
+        val logic = PowerSaveScalingGovernor().createLogic(policy)
+
+        every { policy.max } returns cpuCapacity
+        every { policy.min } returns minSpeed
+
+        logic.onStart()
+
+        logic.onLimit(0.0)
+        verify(exactly = 1) { policy.target = minSpeed }
+
+        logic.onLimit(1.0)
+        verify(exactly = 1) { policy.target = minSpeed }
+    }
+
+    @Test
+    fun testSetStartLimitWithPStates() {
+        val cpuCapacity = 4100.0
+        val firstPState = 1000.0
+        val policy = mockk<ScalingPolicy>(relaxUnitFun = true)
+        val logic = PowerSaveScalingGovernor().createLogic(policy)
+
+        every { policy.max } returns cpuCapacity
+        every { policy.min } returns firstPState
+
+        logic.onStart()
+        verify(exactly = 1) { policy.target = firstPState }
+
+        logic.onLimit(0.0)
+        verify(exactly = 1) { policy.target = firstPState }
+
+        logic.onLimit(1.0)
+        verify(exactly = 1) { policy.target = firstPState }
+    }
+}
diff --git a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PStatePowerDriverTest.kt b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PStatePowerDriverTest.kt
index 35fd7c4c..c39859bf 100644
--- a/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PStatePowerDriverTest.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/power/PStatePowerDriverTest.kt
@@ -52,7 +52,7 @@ internal class PStatePowerDriverTest {
     @Test
     fun testPowerWithSingleCpu() {
         val machine = mockk<SimBareMetalMachine>()
-        val cpu = mockk<SimProcessingUnit>()
+        val cpu = mockk<SimProcessingUnit>(relaxUnitFun = true)
 
         every { cpu.capacity } returns 3200.0
         every { cpu.speed } returns 1200.0
@@ -73,10 +73,8 @@ internal class PStatePowerDriverTest {
     @Test
     fun testPowerWithMultipleCpus() {
         val machine = mockk<SimBareMetalMachine>()
-        val cpus = listOf(
-            mockk<SimProcessingUnit>(),
-            mockk()
-        )
+        val cpu = mockk<SimProcessingUnit>(relaxUnitFun = true)
+        val cpus = listOf(cpu, cpu)
 
         every { cpus[0].capacity } returns 1000.0
         every { cpus[0].speed } returns 1200.0
@@ -100,7 +98,7 @@ internal class PStatePowerDriverTest {
     @Test
     fun testPowerBasedOnUtilization() {
         val machine = mockk<SimBareMetalMachine>()
-        val cpu = mockk<SimProcessingUnit>()
+        val cpu = mockk<SimProcessingUnit>(relaxUnitFun = true)
 
         every { cpu.model.frequency } returns 4200.0