Fix query profiler test basic with concurrent execution

Signed-off-by: Ticheng Lin <[email protected]>

server/src/main/java/org/opensearch/search/profile/query/ConcurrentQueryProfileBreakdown.java

@@ -202,6 +202,11 @@ Map<Collector, Map<String, Long>> buildSliceLevelBreakdown() {
                         // doesn't represent an actual timing; rather, it indicates no invocations.
                         continue;
                     }
+                    if (sliceLeafTimingTypeStartTime == 0L && currentSliceBreakdown.get(timingTypeCountKey) == 0L) {
+                        // This is the case where a slice has 0 invocations for a breakdown type from its leading leaves.
+                        // We should skip the slice start/end time computation since 0 does not represent an actual timing.
+                        continue;
+                    }
                     currentSliceBreakdown.compute(
                         timingTypeSliceStartTimeKey,
                         (key, value) -> (value == null) ? sliceLeafTimingTypeStartTime : Math.min(value, sliceLeafTimingTypeStartTime)
@@ -216,6 +221,12 @@ Map<Collector, Map<String, Long>> buildSliceLevelBreakdown() {
                         (key, value) -> (value == null) ? sliceLeafTimingTypeEndTime : Math.max(value, sliceLeafTimingTypeEndTime)
                     );
                 }
+                // Only when we've checked all leaves in a slice and still find no invocations, then we should set the slice start/end time
+                // to the default 0L.
+                if (currentSliceBreakdown.get(timingTypeCountKey) == 0L) {
+                    currentSliceBreakdown.put(timingTypeSliceStartTimeKey, 0L);
+                    currentSliceBreakdown.put(timingTypeSliceEndTimeKey, 0L);
+                }
                 // compute sliceMaxEndTime as max of sliceEndTime across all timing types
                 sliceMaxEndTime = Math.max(sliceMaxEndTime, currentSliceBreakdown.getOrDefault(timingTypeSliceEndTimeKey, Long.MIN_VALUE));
                 long currentSliceStartTime = currentSliceBreakdown.getOrDefault(timingTypeSliceStartTimeKey, Long.MAX_VALUE);