refactor: OngoingPowerMeasure now records raw measures & timestamps

Author: metacosm

measure/src/main/java/net/laprun/sustainability/power/measure/OngoingPowerMeasure.java

@@ -9,8 +9,8 @@
 import net.laprun.sustainability.power.SensorMetadata;
 
 public class OngoingPowerMeasure implements PowerMeasure {
+    private static final int DEFAULT_SIZE = 32;
     private final SensorMetadata sensorMetadata;
-    private final ComponentMeasure[] measures;
     private final long startedAt;
     private final double[] averages;
     private final Set<Integer> nonZeroComponents;
@@ -20,18 +20,18 @@ public class OngoingPowerMeasure implements PowerMeasure {
     private double maxTotal;
     private double accumulatedTotal;
     private int samples;
+    private final double[][] measures;
+    private long[] timestamps;
 
-    public OngoingPowerMeasure(SensorMetadata sensorMetadata, ComponentMeasure.Factory<?> componentMeasureFactory) {
+    public OngoingPowerMeasure(SensorMetadata sensorMetadata) {
         this.sensorMetadata = sensorMetadata;
         startedAt = System.currentTimeMillis();
 
         final var numComponents = sensorMetadata.componentCardinality();
         // we also record the aggregated total for each component participating in the aggregated value
         final var measuresNb = numComponents + 1;
-        measures = new ComponentMeasure[measuresNb];
-        for (int i = 0; i < measuresNb; i++) {
-            measures[i] = componentMeasureFactory.create();
-        }
+        measures = new double[measuresNb][DEFAULT_SIZE];
+        timestamps = new long[DEFAULT_SIZE];
         totalIndex = numComponents;
         averages = new double[measuresNb];
         // we don't need to record the total component as a non-zero component since it's almost never zero and we compute the std dev separately
@@ -58,14 +58,14 @@ public void recordMeasure(double[] components) {
             if (componentValue != 0) {
                 nonZeroComponents.add(component);
             }
-            measures[component].recordComponentValue(componentValue);
+            recordComponentValue(component, componentValue);
             averages[component] = averages[component] == 0 ? componentValue
                     : (previousSize * averages[component] + componentValue) / samples;
         }
 
         // record min / max totals
         final var recordedTotal = PowerMeasure.sumOfSelectedComponents(components, totalComponents);
-        measures[totalIndex].recordComponentValue(recordedTotal);
+        recordComponentValue(totalIndex, recordedTotal);
         accumulatedTotal += recordedTotal;
         averages[components.length] = averages[components.length] == 0 ? recordedTotal
                 : (previousSize * averages[components.length] + recordedTotal) / samples;
@@ -77,6 +77,23 @@ public void recordMeasure(double[] components) {
         }
     }
 
+    private void recordComponentValue(int component, double value) {
+        final var currentSize = measures[component].length;
+        if (currentSize <= samples) {
+            final var newSize = currentSize * 2;
+            for (int index = 0; index < measures.length; index++) {
+                final var newArray = new double[newSize];
+                System.arraycopy(measures[index], 0, newArray, 0, currentSize);
+                measures[index] = newArray;
+            }
+            final var newTimestamps = new long[newSize];
+            System.arraycopy(timestamps, 0, newTimestamps, 0, currentSize);
+            timestamps = newTimestamps;
+        }
+        timestamps[component] = System.currentTimeMillis();
+        measures[component][samples - 1] = value;
+    }
+
     @Override
     public double total() {
         return accumulatedTotal;
@@ -113,21 +130,23 @@ public StdDev standardDeviations() {
     }
 
     private double standardDeviation(int component) {
-        final var values = measures[component].getComponentRawValues();
+        final var values = measures[component];
         if (samples <= 1) {
             return 0.0;
         }
         final double mean = averages[component];
-        double geometric_deviation_total = 0.0;
-        for (double value : values) {
-            double deviation = value - mean;
-            geometric_deviation_total += (deviation * deviation);
+        double geometricDeviationTotal = 0.0;
+        for (int index = 0; index < samples; index++) {
+            double deviation = values[index] - mean;
+            geometricDeviationTotal += (deviation * deviation);
         }
-        return FastMath.sqrt(geometric_deviation_total / (samples - 1));
+        return FastMath.sqrt(geometricDeviationTotal / (samples - 1));
     }
 
     @Override
     public double[] getMeasuresFor(int component) {
-        return measures[component].getComponentRawValues();
+        final var dest = new double[samples];
+        System.arraycopy(measures[component], 0, dest, 0, samples);
+        return dest;
     }
 }

measure/src/test/java/net/laprun/sustainability/power/measure/OngoingPowerMeasureTest.java

@@ -3,12 +3,10 @@
 import static org.junit.jupiter.api.Assertions.assertArrayEquals;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
-import java.util.List;
 import java.util.Map;
 import java.util.stream.Stream;
 
-import org.junit.jupiter.params.ParameterizedTest;
-import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.jupiter.api.Test;
 
 import net.laprun.sustainability.power.SensorMetadata;
 
@@ -21,13 +19,8 @@ public int componentCardinality() {
         }
     };
 
-    static List<ComponentMeasure.Factory<?>> factories() {
-        return List.of(DescriptiveStatisticsComponentMeasure::new, HdrHistogramComponentMeasure::new);
-    }
-
-    @ParameterizedTest
-    @MethodSource("factories")
-    void testStatistics(ComponentMeasure.Factory<?> factory) {
+    @Test
+    void testStatistics() {
         final var m1c1 = 10.0;
         final var m1c2 = 12.0;
         final var m1c3 = 0.0;
@@ -41,7 +34,7 @@ void testStatistics(ComponentMeasure.Factory<?> factory) {
         final var m3c3 = 0.0;
         final var m3total = m3c1 + m3c2 + m3c3;
 
-        final var measure = new OngoingPowerMeasure(metadata, factory);
+        final var measure = new OngoingPowerMeasure(metadata);
 
         final var components = new double[metadata.componentCardinality()];
         components[0] = m1c1;
@@ -59,9 +52,9 @@ void testStatistics(ComponentMeasure.Factory<?> factory) {
         components[2] = m3c3;
         measure.recordMeasure(components);
 
-//        assertArrayEquals(new double[] {m1c1, m2c1}, measure.getMeasuresFor(0));
-//        assertArrayEquals(new double[] {m1c2, m2c2}, measure.getMeasuresFor(1));
-//        assertArrayEquals(new double[] {m1c3, m2c3}, measure.getMeasuresFor(2));
+        assertArrayEquals(new double[] { m1c1, m2c1, m3c1 }, measure.getMeasuresFor(0));
+        assertArrayEquals(new double[] { m1c2, m2c2, m3c2 }, measure.getMeasuresFor(1));
+        assertArrayEquals(new double[] { m1c3, m2c3, m3c3 }, measure.getMeasuresFor(2));
 
         assertEquals(m1c1 + m1c2 + m1c3 + m2c1 + m2c2 + m2c3 + m3c1 + m3c2 + m3c3, measure.total());
         assertEquals((m1c1 + m1c2 + m1c3 + m2c1 + m2c2 + m2c3 + m3c1 + m3c2 + m3c3) / 3, measure.average());
@@ -74,8 +67,10 @@ void testStatistics(ComponentMeasure.Factory<?> factory) {
         assertEquals((m1c2 + m2c2 + m3c2) / 3, c2Avg);
         assertEquals(0, c3Avg);
 
-        final var stdVarForC1 = Math.sqrt((Math.pow(m1c1 - c1Avg, 2) + Math.pow(m2c1 - c1Avg, 2) + Math.pow(m3c1 - c1Avg, 2)) / (3 - 1));
-        final var stdVarForC2 = Math.sqrt((Math.pow(m1c2 - c2Avg, 2) + Math.pow(m2c2 - c2Avg, 2) + Math.pow(m3c2 - c2Avg, 2)) / (3 - 1));
+        final var stdVarForC1 = Math
+                .sqrt((Math.pow(m1c1 - c1Avg, 2) + Math.pow(m2c1 - c1Avg, 2) + Math.pow(m3c1 - c1Avg, 2)) / (3 - 1));
+        final var stdVarForC2 = Math
+                .sqrt((Math.pow(m1c2 - c2Avg, 2) + Math.pow(m2c2 - c2Avg, 2) + Math.pow(m3c2 - c2Avg, 2)) / (3 - 1));
 
         assertEquals(stdVarForC1, measure.standardDeviations().perComponent()[0], 0.0001,
                 "Standard Deviation did not match the expected value");