Convert to pull-based workload model

This change converts the low-level workload model to be pull-based. This
reduces the overhead that we experienced with our previous co-routine
based approach.

3 files changed, 175 insertions, 52 deletions

diff --git a/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimHypervisorTest.kt b/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimHypervisorTest.kt
index e7fdd4b2..b8eee4f0 100644
--- a/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimHypervisorTest.kt
+++ b/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimHypervisorTest.kt
@@ -26,7 +26,7 @@ import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.test.TestCoroutineScope
 import kotlinx.coroutines.yield
-import org.junit.jupiter.api.Assertions
+import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.assertAll
@@ -51,7 +51,7 @@ internal class SimHypervisorTest {
         scope = TestCoroutineScope()
         clock = DelayControllerClockAdapter(scope)
 
-        val cpuNode = ProcessingNode("Intel", "Xeon", "amd64", 2)
+        val cpuNode = ProcessingNode("Intel", "Xeon", "amd64", 1)
         machineModel = SimMachineModel(
             cpus = List(cpuNode.coreCount) { ProcessingUnit(cpuNode, it, 3200.0) },
             memory = List(4) { MemoryUnit("Crucial", "MTA18ASF4G72AZ-3G2B1", 3200.0, 32_000) }
@@ -59,27 +59,27 @@ internal class SimHypervisorTest {
     }
 
     /**
-     * Test overcommissioning of a hypervisor.
+     * Test overcommitting of resources via the hypervisor with a single VM.
      */
     @Test
-    fun overcommission() {
+    fun testOvercommittedSingle() {
         val listener = object : SimHypervisor.Listener {
-            var totalRequestedBurst = 0L
-            var totalGrantedBurst = 0L
-            var totalOvercommissionedBurst = 0L
+            var totalRequestedWork = 0L
+            var totalGrantedWork = 0L
+            var totalOvercommittedWork = 0L
 
             override fun onSliceFinish(
                 hypervisor: SimHypervisor,
-                requestedBurst: Long,
-                grantedBurst: Long,
-                overcommissionedBurst: Long,
-                interferedBurst: Long,
+                requestedWork: Long,
+                grantedWork: Long,
+                overcommittedWork: Long,
+                interferedWork: Long,
                 cpuUsage: Double,
                 cpuDemand: Double
             ) {
-                totalRequestedBurst += requestedBurst
-                totalGrantedBurst += grantedBurst
-                totalOvercommissionedBurst += overcommissionedBurst
+                totalRequestedWork += requestedWork
+                totalGrantedWork += grantedWork
+                totalOvercommittedWork += overcommittedWork
             }
         }
 
@@ -88,24 +88,84 @@ internal class SimHypervisorTest {
             val workloadA =
                 SimTraceWorkload(
                     sequenceOf(
-                        SimTraceWorkload.Fragment(0, 28L * duration, duration * 1000, 28.0, 2),
-                        SimTraceWorkload.Fragment(0, 3500L * duration, duration * 1000, 3500.0, 2),
-                        SimTraceWorkload.Fragment(0, 0, duration * 1000, 0.0, 2),
-                        SimTraceWorkload.Fragment(0, 183L * duration, duration * 1000, 183.0, 2)
+                        SimTraceWorkload.Fragment(duration * 1000, 28.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 3500.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 0.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 183.0, 1)
+                    ),
+                )
+
+            val machine = SimBareMetalMachine(scope, clock, machineModel)
+            val hypervisor = SimFairShareHypervisor(listener)
+
+            launch {
+                machine.run(hypervisor)
+            }
+
+            yield()
+            launch { hypervisor.createMachine(machineModel).run(workloadA) }
+        }
+
+        scope.advanceUntilIdle()
+        scope.uncaughtExceptions.forEach { it.printStackTrace() }
+
+        assertAll(
+            { assertEquals(emptyList<Throwable>(), scope.uncaughtExceptions, "No errors") },
+            { assertEquals(1113300, listener.totalRequestedWork, "Requested Burst does not match") },
+            { assertEquals(1023300, listener.totalGrantedWork, "Granted Burst does not match") },
+            { assertEquals(90000, listener.totalOvercommittedWork, "Overcommissioned Burst does not match") },
+            { assertEquals(1200000, scope.currentTime) }
+        )
+    }
+
+    /**
+     * Test overcommitting of resources via the hypervisor with two VMs.
+     */
+    @Test
+    fun testOvercommittedDual() {
+        val listener = object : SimHypervisor.Listener {
+            var totalRequestedWork = 0L
+            var totalGrantedWork = 0L
+            var totalOvercommittedWork = 0L
+
+            override fun onSliceFinish(
+                hypervisor: SimHypervisor,
+                requestedWork: Long,
+                grantedWork: Long,
+                overcommittedWork: Long,
+                interferedWork: Long,
+                cpuUsage: Double,
+                cpuDemand: Double
+            ) {
+                totalRequestedWork += requestedWork
+                totalGrantedWork += grantedWork
+                totalOvercommittedWork += overcommittedWork
+            }
+        }
+
+        scope.launch {
+            val duration = 5 * 60L
+            val workloadA =
+                SimTraceWorkload(
+                    sequenceOf(
+                        SimTraceWorkload.Fragment(duration * 1000, 28.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 3500.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 0.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 183.0, 1)
                     ),
                 )
             val workloadB =
                 SimTraceWorkload(
                     sequenceOf(
-                        SimTraceWorkload.Fragment(0, 28L * duration, duration * 1000, 28.0, 2),
-                        SimTraceWorkload.Fragment(0, 3100L * duration, duration * 1000, 3100.0, 2),
-                        SimTraceWorkload.Fragment(0, 0, duration * 1000, 0.0, 2),
-                        SimTraceWorkload.Fragment(0, 73L * duration, duration * 1000, 73.0, 2)
+                        SimTraceWorkload.Fragment(duration * 1000, 28.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 3100.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 0.0, 1),
+                        SimTraceWorkload.Fragment(duration * 1000, 73.0, 1)
                     )
                 )
 
             val machine = SimBareMetalMachine(scope, clock, machineModel)
-            val hypervisor = SimFairSharedHypervisor(scope, clock, listener)
+            val hypervisor = SimFairShareHypervisor(listener)
 
             launch {
                 machine.run(hypervisor)
@@ -117,13 +177,14 @@ internal class SimHypervisorTest {
         }
 
         scope.advanceUntilIdle()
+        scope.uncaughtExceptions.forEach { it.printStackTrace() }
 
         assertAll(
-            { Assertions.assertEquals(emptyList<Throwable>(), scope.uncaughtExceptions, "No errors") },
-            { Assertions.assertEquals(2082000, listener.totalRequestedBurst, "Requested Burst does not match") },
-            { Assertions.assertEquals(2013600, listener.totalGrantedBurst, "Granted Burst does not match") },
-            { Assertions.assertEquals(60000, listener.totalOvercommissionedBurst, "Overcommissioned Burst does not match") },
-            { Assertions.assertEquals(1200001, scope.currentTime) }
+            { assertEquals(emptyList<Throwable>(), scope.uncaughtExceptions, "No errors") },
+            { assertEquals(2082000, listener.totalRequestedWork, "Requested Burst does not match") },
+            { assertEquals(1062000, listener.totalGrantedWork, "Granted Burst does not match") },
+            { assertEquals(1020000, listener.totalOvercommittedWork, "Overcommissioned Burst does not match") },
+            { assertEquals(1200000, scope.currentTime) }
         )
     }
 }
diff --git a/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimMachineTest.kt b/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimMachineTest.kt
index 332ca8e9..1036f1ac 100644
--- a/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimMachineTest.kt
+++ b/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/SimMachineTest.kt
@@ -23,15 +23,20 @@
 package org.opendc.simulator.compute
 
 import kotlinx.coroutines.*
+import kotlinx.coroutines.flow.toList
 import kotlinx.coroutines.test.TestCoroutineScope
 import kotlinx.coroutines.test.runBlockingTest
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertDoesNotThrow
+import org.junit.jupiter.api.assertThrows
 import org.opendc.simulator.compute.model.MemoryUnit
 import org.opendc.simulator.compute.model.ProcessingNode
 import org.opendc.simulator.compute.model.ProcessingUnit
 import org.opendc.simulator.compute.workload.SimFlopsWorkload
+import org.opendc.simulator.compute.workload.SimResourceCommand
+import org.opendc.simulator.compute.workload.SimWorkload
 import org.opendc.simulator.utils.DelayControllerClockAdapter
 
 /**
@@ -58,7 +63,7 @@ class SimMachineTest {
         val machine = SimBareMetalMachine(testScope, clock, machineModel)
 
         testScope.runBlockingTest {
-            machine.run(SimFlopsWorkload(2_000, 2, utilization = 1.0))
+            machine.run(SimFlopsWorkload(2_000, utilization = 1.0))
 
             // Two cores execute 1000 MFlOps per second (1000 ms)
             assertEquals(1000, testScope.currentTime)
@@ -72,12 +77,83 @@ class SimMachineTest {
         val machine = SimBareMetalMachine(testScope, clock, machineModel)
 
         testScope.runBlockingTest {
-            machine.run(SimFlopsWorkload(2_000, 2, utilization = 1.0))
-            assertEquals(1.0, machine.usage.value)
+            val res = mutableListOf<Double>()
+            val job = launch { machine.usage.toList(res) }
 
-            // Wait for the usage to reset
-            delay(1)
-            assertEquals(0.0, machine.usage.value)
+            machine.run(SimFlopsWorkload(2_000, utilization = 1.0))
+
+            job.cancel()
+            assertEquals(listOf(0.0, 0.5, 1.0, 0.5, 0.0), res) { "Machine is fully utilized" }
+        }
+    }
+
+    @Test
+    fun testInterrupt() {
+        val testScope = TestCoroutineScope()
+        val clock = DelayControllerClockAdapter(testScope)
+        val machine = SimBareMetalMachine(testScope, clock, machineModel)
+
+        val workload = object : SimWorkload {
+            override fun onStart(ctx: SimExecutionContext) {}
+
+            override fun onStart(ctx: SimExecutionContext, cpu: Int): SimResourceCommand {
+                ctx.interrupt(cpu)
+                return SimResourceCommand.Exit
+            }
+
+            override fun onNext(ctx: SimExecutionContext, cpu: Int, remainingWork: Double): SimResourceCommand {
+                throw IllegalStateException()
+            }
+        }
+
+        assertDoesNotThrow {
+            testScope.runBlockingTest { machine.run(workload) }
+        }
+    }
+
+    @Test
+    fun testExceptionPropagationOnStart() {
+        val testScope = TestCoroutineScope()
+        val clock = DelayControllerClockAdapter(testScope)
+        val machine = SimBareMetalMachine(testScope, clock, machineModel)
+
+        val workload = object : SimWorkload {
+            override fun onStart(ctx: SimExecutionContext) {}
+
+            override fun onStart(ctx: SimExecutionContext, cpu: Int): SimResourceCommand {
+                throw IllegalStateException()
+            }
+
+            override fun onNext(ctx: SimExecutionContext, cpu: Int, remainingWork: Double): SimResourceCommand {
+                throw IllegalStateException()
+            }
+        }
+
+        assertThrows<IllegalStateException> {
+            testScope.runBlockingTest { machine.run(workload) }
+        }
+    }
+
+    @Test
+    fun testExceptionPropagationOnNext() {
+        val testScope = TestCoroutineScope()
+        val clock = DelayControllerClockAdapter(testScope)
+        val machine = SimBareMetalMachine(testScope, clock, machineModel)
+
+        val workload = object : SimWorkload {
+            override fun onStart(ctx: SimExecutionContext) {}
+
+            override fun onStart(ctx: SimExecutionContext, cpu: Int): SimResourceCommand {
+                return SimResourceCommand.Consume(1.0, 1.0)
+            }
+
+            override fun onNext(ctx: SimExecutionContext, cpu: Int, remainingWork: Double): SimResourceCommand {
+                throw IllegalStateException()
+            }
+        }
+
+        assertThrows<IllegalStateException> {
+            testScope.runBlockingTest { machine.run(workload) }
         }
     }
 }
diff --git a/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/workload/SimFlopsWorkloadTest.kt b/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/workload/SimFlopsWorkloadTest.kt
index 51bed76c..b3e57453 100644
--- a/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/workload/SimFlopsWorkloadTest.kt
+++ b/simulator/opendc-simulator/opendc-simulator-compute/src/test/kotlin/org/opendc/simulator/compute/workload/SimFlopsWorkloadTest.kt
@@ -32,42 +32,28 @@ class SimFlopsWorkloadTest {
     @Test
     fun testFlopsNonNegative() {
         assertThrows<IllegalArgumentException>("FLOPs must be non-negative") {
-            SimFlopsWorkload(-1, 1)
-        }
-    }
-
-    @Test
-    fun testCoresNonZero() {
-        assertThrows<IllegalArgumentException>("Cores cannot be zero") {
-            SimFlopsWorkload(1, 0)
-        }
-    }
-
-    @Test
-    fun testCoresPositive() {
-        assertThrows<IllegalArgumentException>("Cores cannot be negative") {
-            SimFlopsWorkload(1, -1)
+            SimFlopsWorkload(-1)
         }
     }
 
     @Test
     fun testUtilizationNonZero() {
         assertThrows<IllegalArgumentException>("Utilization cannot be zero") {
-            SimFlopsWorkload(1, 1, 0.0)
+            SimFlopsWorkload(1, 0.0)
         }
     }
 
     @Test
     fun testUtilizationPositive() {
         assertThrows<IllegalArgumentException>("Utilization cannot be negative") {
-            SimFlopsWorkload(1, 1, -1.0)
+            SimFlopsWorkload(1, -1.0)
         }
     }
 
     @Test
     fun testUtilizationNotLargerThanOne() {
         assertThrows<IllegalArgumentException>("Utilization cannot be larger than one") {
-            SimFlopsWorkload(1, 1, 2.0)
+            SimFlopsWorkload(1, 2.0)
         }
     }
 }