simulator: Add memory resource

This change introduces a memory resource which can be used to model
memory usage. The SimMachineContext now exposes a memory field of type
SimMemory which provides access to this resource and allows workloads to
start a consumer on this resource.

4 files changed, 52 insertions, 7 deletions

diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimAbstractMachine.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimAbstractMachine.kt
index e12ac72b..93d306cf 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimAbstractMachine.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimAbstractMachine.kt
@@ -63,6 +63,11 @@ public abstract class SimAbstractMachine(
     protected abstract val cpus: List<SimProcessingUnit>
 
     /**
+     * The memory interface of the machine.
+     */
+    protected val memory: SimMemory = Memory(SimResourceSource(model.memory.sumOf { it.size }.toDouble(), interpreter), model.memory)
+
+    /**
      * A flag to indicate that the machine is terminated.
      */
     private var isTerminated = false
@@ -163,8 +168,15 @@ public abstract class SimAbstractMachine(
 
         override val cpus: List<SimProcessingUnit> = this@SimAbstractMachine.cpus
 
-        override val memory: List<MemoryUnit> = model.memory
+        override val memory: SimMemory = this@SimAbstractMachine.memory
 
         override fun close() = cancel()
     }
+
+    /**
+     * The [SimMemory] implementation for a machine.
+     */
+    private class Memory(source: SimResourceSource, override val models: List<MemoryUnit>) : SimMemory, SimResourceProvider by source {
+        override fun toString(): String = "SimAbstractMachine.Memory"
+    }
 }
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimBareMetalMachine.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimBareMetalMachine.kt
index 5d5d1e5a..642873fd 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimBareMetalMachine.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimBareMetalMachine.kt
@@ -76,9 +76,7 @@ public class SimBareMetalMachine(
             get() = source.capacity
             set(value) {
                 // Clamp the capacity of the CPU between [0.0, maxFreq]
-                if (value >= 0.0 && value <= model.frequency) {
-                    source.capacity = value
-                }
+                source.capacity = value.coerceIn(0.0, model.frequency)
             }
 
         override fun toString(): String = "SimBareMetalMachine.Cpu[model=$model]"
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimMachineContext.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimMachineContext.kt
index 5cbabc86..391442ec 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimMachineContext.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimMachineContext.kt
@@ -22,7 +22,6 @@
 
 package org.opendc.simulator.compute
 
-import org.opendc.simulator.compute.model.MemoryUnit
 import org.opendc.simulator.resources.SimResourceInterpreter
 
 /**
@@ -47,9 +46,9 @@ public interface SimMachineContext : AutoCloseable {
     public val cpus: List<SimProcessingUnit>
 
     /**
-     * The memory available on the machine
+     * The memory interface of the machine.
      */
-    public val memory: List<MemoryUnit>
+    public val memory: SimMemory
 
     /**
      * Stop the workload.
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimMemory.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimMemory.kt
new file mode 100644
index 00000000..6623df23
--- /dev/null
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/SimMemory.kt
@@ -0,0 +1,36 @@
+/*
+ * 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
+
+import org.opendc.simulator.compute.model.MemoryUnit
+import org.opendc.simulator.resources.SimResourceProvider
+
+/**
+ * An interface to control the memory usage of simulated workloads.
+ */
+public interface SimMemory : SimResourceProvider {
+    /**
+     * The models representing the static information of the memory units supporting this interface.
+     */
+    public val models: List<MemoryUnit>
+}