fix(simulator): Flush results before accessing counters

This change updates the simulator implementation to flush the active
progress when accessing the hypervisor counters. Previously, if the
counters were accessed, while the mux or consumer was in progress, its
counter values were not accurate.

2 files changed, 24 insertions, 2 deletions

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 07465126..b7f70749 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
@@ -137,7 +137,9 @@ public abstract class SimAbstractHypervisor(
 
     /* FlowConvergenceListener */
     override fun onConverge(now: Long, delta: Long) {
-        _counters.record()
+        if (delta > 0) {
+            _counters.record()
+        }
 
         val load = cpuDemand / cpuCapacity
         for (governor in governors) {
@@ -274,6 +276,10 @@ public abstract class SimAbstractHypervisor(
         fun close() {
             switch.removeInput(source)
         }
+
+        fun flush() {
+            switch.flushCounters(source)
+        }
     }
 
     /**
@@ -337,6 +343,11 @@ public abstract class SimAbstractHypervisor(
             cpuTime[2] += ((demandDelta - actualDelta) * d).roundToLong()
             cpuTime[3] += (interferenceDelta * d).roundToLong()
         }
+
+        override fun flush() {
+            hv.mux.flushCounters()
+            record()
+        }
     }
 
     /**
@@ -348,10 +359,16 @@ public abstract class SimAbstractHypervisor(
         override val cpuActiveTime: Long
             get() = (cpus.sumOf { it.counters.actual } * d).roundToLong()
         override val cpuIdleTime: Long
-            get() = (cpus.sumOf { it.counters.actual + it.counters.remaining } * d).roundToLong()
+            get() = (cpus.sumOf { it.counters.remaining } * d).roundToLong()
         override val cpuStealTime: Long
             get() = (cpus.sumOf { it.counters.demand - it.counters.actual } * d).roundToLong()
         override val cpuLostTime: Long
             get() = (cpus.sumOf { it.counters.interference } * d).roundToLong()
+
+        override fun flush() {
+            for (cpu in cpus) {
+                cpu.flush()
+            }
+        }
     }
 }
diff --git a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorCounters.kt b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorCounters.kt
index 030d9c5f..63fee507 100644
--- a/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorCounters.kt
+++ b/opendc-simulator/opendc-simulator-compute/src/main/kotlin/org/opendc/simulator/compute/kernel/SimHypervisorCounters.kt
@@ -45,4 +45,9 @@ public interface SimHypervisorCounters {
      * The amount of CPU time (in milliseconds) that was lost due to interference between virtual machines.
      */
     public val cpuLostTime: Long
+
+    /**
+     * Flush the counter values.
+     */
+    public fun flush()
 }