perf(simulator): Make convergence callback optional

This change adds two new properties for controlling whether the
convergence callbacks of the source and consumer respectively should be
invoked. This saves a lot of unnecessary calls for stages that do not
have any implementation of the `onConvergence` method.

8 files changed, 23 insertions, 20 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 6a62d8a5..60a10f20 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
@@ -43,9 +43,9 @@ import kotlin.coroutines.resume
  */
 public abstract class SimAbstractMachine(
     protected val engine: FlowEngine,
-    final override val parent: FlowSystem?,
+    private val parent: FlowConvergenceListener?,
     final override val model: MachineModel
-) : SimMachine, FlowSystem {
+) : SimMachine, FlowConvergenceListener {
     /**
      * The resources allocated for this machine.
      */
@@ -116,6 +116,10 @@ public abstract class SimAbstractMachine(
         cancel()
     }
 
+    override fun onConverge(now: Long, delta: Long) {
+        parent?.onConverge(now, delta)
+    }
+
     /**
      * Cancel the workload that is currently running on the machine.
      */
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 37cf282b..0bcf5957 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
@@ -46,7 +46,7 @@ public class SimBareMetalMachine(
     model: MachineModel,
     powerDriver: PowerDriver,
     public val psu: SimPsu = SimPsu(500.0, mapOf(1.0 to 1.0)),
-    parent: FlowSystem? = null,
+    parent: FlowConvergenceListener? = null,
 ) : SimAbstractMachine(engine, parent, model) {
     /**
      * The power draw of the machine onto the PSU.
@@ -66,7 +66,7 @@ public class SimBareMetalMachine(
      */
     private val powerDriverLogic = powerDriver.createLogic(this, cpus)
 
-    override fun onConverge(timestamp: Long) {
+    override fun onConverge(now: Long, delta: Long) {
         psu.update()
     }
 
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/device/SimPsu.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/device/SimPsu.kt
index 62d91c0b..09defbb5 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/device/SimPsu.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/device/SimPsu.kt
@@ -83,6 +83,7 @@ public class SimPsu(
     override fun createSource(): FlowSource = object : FlowSource {
         override fun onStart(conn: FlowConnection, now: Long) {
             _ctx = conn
+            conn.shouldSourceConverge = true
         }
 
         override fun onStop(conn: FlowConnection, now: Long, delta: Long) {
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimAbstractHypervisor.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimAbstractHypervisor.kt
index b145eefc..bcba8e8e 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimAbstractHypervisor.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimAbstractHypervisor.kt
@@ -145,8 +145,6 @@ public abstract class SimAbstractHypervisor(
                 interferenceDomain?.leave(interferenceKey)
             }
         }
-
-        override fun onConverge(timestamp: Long) {}
     }
 
     /**
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisor.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisor.kt
index 36ab7c1c..b0515c6e 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisor.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisor.kt
@@ -28,8 +28,8 @@ import org.opendc.simulator.compute.kernel.cpufreq.ScalingGovernor
 import org.opendc.simulator.compute.kernel.interference.VmInterferenceDomain
 import org.opendc.simulator.compute.model.MachineModel
 import org.opendc.simulator.compute.workload.SimWorkload
+import org.opendc.simulator.flow.FlowConvergenceListener
 import org.opendc.simulator.flow.FlowEngine
-import org.opendc.simulator.flow.FlowSystem
 import org.opendc.simulator.flow.mux.FlowMultiplexer
 import org.opendc.simulator.flow.mux.MaxMinFlowMultiplexer
 
@@ -45,7 +45,7 @@ import org.opendc.simulator.flow.mux.MaxMinFlowMultiplexer
  */
 public class SimFairShareHypervisor(
     engine: FlowEngine,
-    private val parent: FlowSystem? = null,
+    private val parent: FlowConvergenceListener? = null,
     scalingGovernor: ScalingGovernor? = null,
     interferenceDomain: VmInterferenceDomain? = null,
     private val listener: SimHypervisor.Listener? = null
@@ -57,11 +57,9 @@ public class SimFairShareHypervisor(
         return SwitchSystem(ctx).switch
     }
 
-    private inner class SwitchSystem(private val ctx: SimMachineContext) : FlowSystem {
+    private inner class SwitchSystem(private val ctx: SimMachineContext) : FlowConvergenceListener {
         val switch = MaxMinFlowMultiplexer(engine, this, interferenceDomain)
 
-        override val parent: FlowSystem? = this@SimFairShareHypervisor.parent
-
         private var lastCpuUsage = 0.0
         private var lastCpuDemand = 0.0
         private var lastDemand = 0.0
@@ -70,11 +68,11 @@ public class SimFairShareHypervisor(
         private var lastInterference = 0.0
         private var lastReport = Long.MIN_VALUE
 
-        override fun onConverge(timestamp: Long) {
+        override fun onConverge(now: Long, delta: Long) {
             val listener = listener ?: return
             val counters = switch.counters
 
-            if (timestamp > lastReport) {
+            if (now > lastReport) {
                 listener.onSliceFinish(
                     this@SimFairShareHypervisor,
                     counters.demand - lastDemand,
@@ -85,7 +83,7 @@ public class SimFairShareHypervisor(
                     lastCpuDemand
                 )
             }
-            lastReport = timestamp
+            lastReport = now
 
             lastCpuDemand = switch.outputs.sumOf { it.demand }
             lastCpuUsage = switch.outputs.sumOf { it.rate }
@@ -96,6 +94,8 @@ public class SimFairShareHypervisor(
 
             val load = lastCpuDemand / ctx.cpus.sumOf { it.model.frequency }
             triggerGovernors(load)
+
+            parent?.onConverge(now, delta)
         }
     }
 }
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisorProvider.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisorProvider.kt
index bfa099fb..e0a70926 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisorProvider.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimFairShareHypervisorProvider.kt
@@ -24,8 +24,8 @@ package org.opendc.simulator.compute.kernel
 
 import org.opendc.simulator.compute.kernel.cpufreq.ScalingGovernor
 import org.opendc.simulator.compute.kernel.interference.VmInterferenceDomain
+import org.opendc.simulator.flow.FlowConvergenceListener
 import org.opendc.simulator.flow.FlowEngine
-import org.opendc.simulator.flow.FlowSystem
 
 /**
  * A [SimHypervisorProvider] for the [SimFairShareHypervisor] implementation.
@@ -35,7 +35,7 @@ public class SimFairShareHypervisorProvider : SimHypervisorProvider {
 
     override fun create(
         engine: FlowEngine,
-        parent: FlowSystem?,
+        parent: FlowConvergenceListener?,
         scalingGovernor: ScalingGovernor?,
         interferenceDomain: VmInterferenceDomain?,
         listener: SimHypervisor.Listener?
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorProvider.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorProvider.kt
index 97f07097..dad2cc3b 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorProvider.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorProvider.kt
@@ -24,8 +24,8 @@ package org.opendc.simulator.compute.kernel
 
 import org.opendc.simulator.compute.kernel.cpufreq.ScalingGovernor
 import org.opendc.simulator.compute.kernel.interference.VmInterferenceDomain
+import org.opendc.simulator.flow.FlowConvergenceListener
 import org.opendc.simulator.flow.FlowEngine
-import org.opendc.simulator.flow.FlowSystem
 
 /**
  * A service provider interface for constructing a [SimHypervisor].
@@ -44,7 +44,7 @@ public interface SimHypervisorProvider {
      */
     public fun create(
         engine: FlowEngine,
-        parent: FlowSystem? = null,
+        parent: FlowConvergenceListener? = null,
         scalingGovernor: ScalingGovernor? = null,
         interferenceDomain: VmInterferenceDomain? = null,
         listener: SimHypervisor.Listener? = null
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimSpaceSharedHypervisorProvider.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimSpaceSharedHypervisorProvider.kt
index 7869d72d..93921eb9 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimSpaceSharedHypervisorProvider.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimSpaceSharedHypervisorProvider.kt
@@ -24,8 +24,8 @@ package org.opendc.simulator.compute.kernel
 
 import org.opendc.simulator.compute.kernel.cpufreq.ScalingGovernor
 import org.opendc.simulator.compute.kernel.interference.VmInterferenceDomain
+import org.opendc.simulator.flow.FlowConvergenceListener
 import org.opendc.simulator.flow.FlowEngine
-import org.opendc.simulator.flow.FlowSystem
 
 /**
  * A [SimHypervisorProvider] for the [SimSpaceSharedHypervisor] implementation.
@@ -35,7 +35,7 @@ public class SimSpaceSharedHypervisorProvider : SimHypervisorProvider {
 
     override fun create(
         engine: FlowEngine,
-        parent: FlowSystem?,
+        parent: FlowConvergenceListener?,
         scalingGovernor: ScalingGovernor?,
         interferenceDomain: VmInterferenceDomain?,
         listener: SimHypervisor.Listener?