segstore: Add assert on item count for iteration benchmarks

This patch adds asserts on the item count when iterating the segment
store in the benchmark. It makes sure that all iterations actually
iterate over all the elements of the segment and does not give a false
impression of performance if there is a bug in the iterator.

Also remove the System.gc() that are not useful to the test

Change-Id: I87acbb264703f06a166239655f3911697c17126e
Signed-off-by: Geneviève Bastien <gbastien+lttng@versatic.net>
Reviewed-on: https://git.eclipse.org/r/85724
Reviewed-by: Hudson CI
Reviewed-by: Alexandre Montplaisir <alexmonthy@efficios.com>

diff --git a/statesystem/org.eclipse.tracecompass.segmentstore.core.tests/perf/org/eclipse/tracecompass/analysis/timing/core/tests/store/SegmentStoreBenchmark.java b/statesystem/org.eclipse.tracecompass.segmentstore.core.tests/perf/org/eclipse/tracecompass/analysis/timing/core/tests/store/SegmentStoreBenchmark.java
index 29435acde33bdc8223a855d9ef0a13a6de7c353a..12f115ff4dab4d08d87e49bf23b49050d868dfe7 100644 (file)
--- a/statesystem/org.eclipse.tracecompass.segmentstore.core.tests/perf/org/eclipse/tracecompass/analysis/timing/core/tests/store/SegmentStoreBenchmark.java
+++ b/statesystem/org.eclipse.tracecompass.segmentstore.core.tests/perf/org/eclipse/tracecompass/analysis/timing/core/tests/store/SegmentStoreBenchmark.java
@@ -9,8 +9,11 @@
 
 package org.eclipse.tracecompass.analysis.timing.core.tests.store;
 
+import static org.junit.Assert.assertEquals;
+
 import java.util.Arrays;
 import java.util.Comparator;
+import java.util.Iterator;
 import java.util.Random;
 
 import org.eclipse.jdt.annotation.NonNull;
@@ -98,7 +101,6 @@ public class SegmentStoreBenchmark {
         for (int i = 0; i < DEFAULT_LOOP_COUNT; i++) {
             fSegStore.clear();
 
-            System.gc();
             pMorderedInsertion.start();
             populate(size, fuzz, fSegStore, 0, getSegmentStoreSize());
             pMorderedInsertion.stop();
@@ -173,25 +175,24 @@ public class SegmentStoreBenchmark {
         for (int i = 0; i < DEFAULT_LOOP_COUNT; i++) {
             fSegStore.clear();
 
-            System.gc();
             pMinsertion.start();
             populate(size, fuzz, fSegStore, 0, getSegmentStoreSize());
             pMinsertion.stop();
 
-            System.gc();
             pMiterateStart.start();
-            sortedIterate(fSegStore, SegmentComparators.INTERVAL_START_COMPARATOR);
+            int count = sortedIterate(fSegStore, SegmentComparators.INTERVAL_START_COMPARATOR);
             pMiterateStart.stop();
+            assertEquals(fSegStore.size(), count);
 
-            System.gc();
             pMiterateEnd.start();
-            sortedIterate(fSegStore, SegmentComparators.INTERVAL_END_COMPARATOR);
+            count = sortedIterate(fSegStore, SegmentComparators.INTERVAL_END_COMPARATOR);
             pMiterateEnd.stop();
+            assertEquals(fSegStore.size(), count);
 
-            System.gc();
             pMiterateDuration.start();
-            sortedIterate(fSegStore, SegmentComparators.INTERVAL_LENGTH_COMPARATOR);
+            count = sortedIterate(fSegStore, SegmentComparators.INTERVAL_LENGTH_COMPARATOR);
             pMiterateDuration.stop();
+            assertEquals(fSegStore.size(), count);
         }
 
         pMinsertion.commit();
@@ -209,25 +210,23 @@ public class SegmentStoreBenchmark {
         for (int i = 0; i < DEFAULT_LOOP_COUNT; i++) {
             fSegStore.clear();
 
-            System.gc();
             pMinsertion1.start();
             populate(size, fuzz, fSegStore, 0, getSegmentStoreSize() / 2);
             pMinsertion1.stop();
 
-            System.gc();
             pMiterate1.start();
-            iterate(fSegStore);
+            int count = iterate(fSegStore);
             pMiterate1.stop();
+            assertEquals(fSegStore.size(), count);
 
-            System.gc();
             pMinsertion2.start();
             populate(size, fuzz, fSegStore, getSegmentStoreSize() / 2 + 1, getSegmentStoreSize());
             pMinsertion2.stop();
 
-            System.gc();
             pMiterate2.start();
-            iterate(fSegStore);
+            count = iterate(fSegStore);
             pMiterate2.stop();
+            assertEquals(fSegStore.size(), count);
         }
 
         pMinsertion1.commit();
@@ -236,17 +235,19 @@ public class SegmentStoreBenchmark {
         pMiterate2.commit();
     }
 
-    private static Object iterate(Iterable<@NonNull ISegment> store) {
-        Object shutupCompilerWarnings = null;
-        for (ISegment elem : store) {
-            shutupCompilerWarnings = elem;
+    private static int iterate(Iterable<@NonNull ISegment> store) {
+        int count = 0;
+        Iterator<@NonNull ISegment> iterator = store.iterator();
+        while (iterator.hasNext()) {
+            count++;
+            iterator.next();
         }
-        return shutupCompilerWarnings;
+        return count;
     }
 
-    private static void sortedIterate(ISegmentStore<@NonNull ISegment> store, @NonNull Comparator<@NonNull ISegment> order) {
+    private static int sortedIterate(ISegmentStore<@NonNull ISegment> store, @NonNull Comparator<@NonNull ISegment> order) {
         Iterable<@NonNull ISegment> iterable = store.iterator(order);
-        iterate(iterable);
+        return iterate(iterable);
     }
 
     private static void populate(int size, int[] fuzz, ISegmentStore<@NonNull ISegment> store, long low, long high) {