Improve Archive Region Calculation (#211) (#369)

* improve archive region calculation (#211)

* Add comment for Archive Region availability

* Update parser/src/main/java/com/microsoft/gctoolkit/parser/UnifiedG1GCParser.java

* Update parser/src/main/java/com/microsoft/gctoolkit/parser/UnifiedG1GCParser.java

* Update parser/src/main/java/com/microsoft/gctoolkit/parser/UnifiedG1GCParser.java

* Update parser/src/main/java/com/microsoft/gctoolkit/parser/UnifiedG1GCParser.java

---------

Co-authored-by: Martijn Verburg <martijnverburg@gmail.com>

api/src/main/java/com/microsoft/gctoolkit/event/g1gc/G1GCPauseEvent.java

@@ -29,6 +29,7 @@ public abstract class G1GCPauseEvent extends G1GCEvent {
     private RegionSummary archiveRegion;
 
     private CPUSummary cpuSummary;
+    private int heapRegionSize;
 
     public G1GCPauseEvent(DateTimeStamp timeStamp, GarbageCollectionTypes type, GCCause cause, double duration) {
         super(timeStamp, type, cause, duration);
@@ -102,10 +103,15 @@ public abstract class G1GCPauseEvent extends G1GCEvent {
         } else if (getSurvivor() == null) {
             return getHeap().minus(getEden());
         } else {
-            return new MemoryPoolSummary(getHeap().getOccupancyBeforeCollection() - this.getEden().getOccupancyBeforeCollection() - getSurvivor().getOccupancyBeforeCollection(),
-                    getHeap().getSizeBeforeCollection() - getEden().getSizeBeforeCollection() - getSurvivor().getOccupancyBeforeCollection(),
-                    getHeap().getOccupancyAfterCollection() - getEden().getOccupancyAfterCollection() - getSurvivor().getOccupancyAfterCollection(),
-                    getHeap().getSizeAfterCollection() - getEden().getSizeAfterCollection() - getSurvivor().getOccupancyAfterCollection());
+            final RegionSummary summary = getArchiveRegionSummary();
+            final long archiveRegionByteBefore = summary.getBefore() * heapRegionSize * 1024L;
+            final long archiveRegionByteAfter = summary.getAfter() * heapRegionSize * 1024L;
+            final long archiveRegionByteAssigned = summary.getAssigned() * heapRegionSize * 1024L;
+
+            return new MemoryPoolSummary(getHeap().getOccupancyBeforeCollection() - this.getEden().getOccupancyBeforeCollection() - getSurvivor().getOccupancyBeforeCollection() - archiveRegionByteAssigned,
+                    getHeap().getSizeBeforeCollection() - getEden().getSizeBeforeCollection() - getSurvivor().getOccupancyBeforeCollection() - archiveRegionByteBefore,
+                    getHeap().getOccupancyAfterCollection() - getEden().getOccupancyAfterCollection() - getSurvivor().getOccupancyAfterCollection() - archiveRegionByteAssigned,
+                    getHeap().getSizeAfterCollection() - getEden().getSizeAfterCollection() - getSurvivor().getOccupancyAfterCollection() - archiveRegionByteAfter);
         }
     }
 
@@ -121,4 +127,7 @@ public abstract class G1GCPauseEvent extends G1GCEvent {
         return this.cpuSummary;
     }
 
+    public void addHeapRegionSize(int heapRegionSize) {
+        this.heapRegionSize = heapRegionSize;
+    }
 }

parser/src/main/java/com/microsoft/gctoolkit/parser/G1GCForwardReference.java

@@ -544,6 +544,7 @@ class G1GCForwardReference extends ForwardReference {
         SurvivorMemoryPoolSummary survivor = getSurvivorMemoryPoolSummary();
         MemoryPoolSummary tenured = getMemoryPoolSummary(OLD_OCCUPANCY_BEFORE_COLLECTION);
         MemoryPoolSummary humongous = getMemoryPoolSummary(HUMONGOUS_OCCUPANCY_BEFORE_COLLECTION);
+        collection.addHeapRegionSize(heapRegionSize);
         if (heap != null && eden != null && survivor != null) {
             collection.addMemorySummary(eden, survivor, heap);
         } else if (eden == null && survivor == null && heap != null) {

parser/src/main/java/com/microsoft/gctoolkit/parser/UnifiedG1GCParser.java

@@ -494,6 +494,7 @@ public class UnifiedG1GCParser extends UnifiedGCLogParser implements UnifiedG1GC
                 forwardReference.setHumongousRegionSummary(summary);
                 break;
             case "Archive":
+                // Archive Region type is only available in JDK 14 and 17.
                 forwardReference.setArchiveRegionSummary(summary);
                 break;
             default: