GH-599 handle instances with a deep path to the GC root in the correct order

Author: thurka

visualvm/libs.profiler/lib.profiler.heap/src/org/graalvm/visualvm/lib/jfluid/heap/HprofHeap.java

@@ -103,7 +103,7 @@ class HprofHeap implements Heap {
     private static final boolean DEBUG = false;
 
     private static final String SNAPSHOT_ID = "NBPHD";
-    private static final int SNAPSHOT_VERSION  = 4;
+    private static final int SNAPSHOT_VERSION  = 5;
     private static final String OS_PROP = "os.name";
 
     //~ Instance fields ----------------------------------------------------------------------------------------------------------
@@ -728,6 +728,41 @@ void computeRetainedSize() {
         new TreeObject(this,leaves).computeTrees();
         domTree = new DominatorTree(this,nearestGCRoot.getMultipleParents());
         domTree.computeDominators();
+
+        // deep path first
+        try {
+            LongBuffer deepPathBuffer = nearestGCRoot.getDeepPathBuffer();
+            LongBuffer deepPath = deepPathBuffer.revertBuffer();
+
+            deepPathBuffer.reset();
+            deepPathBuffer.delete();
+            if (deepPath.hasData()) {
+                for (long deepObjId = deepPath.readLong(); deepObjId != 0; deepObjId = deepPath.readLong()) {
+                    LongMap.Entry deepObjEntry = idToOffsetMap.get(deepObjId);
+                    assert deepObjEntry.isDeepObj();
+                    long idomId = domTree.getIdomId(deepObjId, deepObjEntry);
+                    LongMap.Entry idomEntry = idToOffsetMap.get(idomId);
+
+                    if (!deepObjEntry.isTreeObj()) {
+                        Instance deepInstance = getInstanceByID(deepObjId);
+                        long size = deepInstance.getSize();
+                        long origSize = deepObjEntry.getRetainedSize();
+
+                        if (origSize < 0) origSize = 0;
+                        deepObjEntry.setRetainedSize(origSize + size);
+                    }
+                    if (idomEntry.isDeepObj() && !idomEntry.isTreeObj()) {
+                        long origSize = idomEntry.getRetainedSize();
+                        if (origSize < 0) origSize = 0;
+                        idomEntry.setRetainedSize(origSize + deepObjEntry.getRetainedSize());
+                    }
+                }
+            }
+            deepPath.delete();
+        } catch (IOException ex) {
+            throw new IllegalArgumentException(ex.getLocalizedMessage(), ex);
+        }
+
         long[] offset = new long[] { allInstanceDumpBounds.startOffset };
 
         for (long counter=0; offset[0] < allInstanceDumpBounds.endOffset; counter++) {
@@ -748,9 +783,10 @@ void computeRetainedSize() {
             LongMap.Entry instanceEntry = idToOffsetMap.get(instanceId);
             long idom = domTree.getIdomId(instanceId,instanceEntry);
             boolean isTreeObj = instanceEntry.isTreeObj();
+            boolean deepObj = instanceEntry.isDeepObj();
             long instSize = 0;
 
-            if (!isTreeObj && (instanceEntry.getNearestGCRootPointer() != 0 || gcRoots.getGCRoots(new Long(instanceId)) != null)) {
+            if (!deepObj && !isTreeObj && (instanceEntry.getNearestGCRootPointer() != 0 || gcRoots.getGCRoots(new Long(instanceId)) != null)) {
                 long origSize = instanceEntry.getRetainedSize();
                 if (origSize < 0) origSize = 0;
                 Instance instance = getInstanceByOffset(new long[] {start});
@@ -759,9 +795,13 @@ void computeRetainedSize() {
             }
             if (idom != 0) {
                 long size;
-                LongMap.Entry entry;
+                LongMap.Entry entry = idToOffsetMap.get(idom);
 
-                if (isTreeObj) {
+                if (entry.isDeepObj()) {
+                    continue;
+                } else if (isTreeObj) {
+                    size = instanceEntry.getRetainedSize();
+                } else if (deepObj) {
                     size = instanceEntry.getRetainedSize();
                 } else {
                     assert instSize != 0;

visualvm/libs.profiler/lib.profiler.heap/src/org/graalvm/visualvm/lib/jfluid/heap/LongMap.java

@@ -56,6 +56,7 @@ class Entry extends AbstractLongMap.Entry {
         private static final byte NUMBER_LIST = 1;
         private static final byte GC_ROOT = 2;
         private static final byte TREE_OBJ = 4;
+        private static final byte DEEP_OBJ = 8;
 
         //~ Instance fields ------------------------------------------------------------------------------------------------------
 
@@ -91,6 +92,15 @@ boolean isTreeObj() {
             return (getFlags() & TREE_OBJ) != 0;
         }
 
+        void setDeepObj() {
+            byte flags = (byte)(getFlags() | DEEP_OBJ);
+            setFlags(flags);
+        }
+
+        boolean isDeepObj() {
+            return (getFlags() & DEEP_OBJ) != 0;
+        }
+
         boolean hasOnlyOneReference() {
             return (getFlags() & NUMBER_LIST) == 0;
         }

visualvm/libs.profiler/lib.profiler.heap/src/org/graalvm/visualvm/lib/jfluid/heap/NearestGCRoot.java

@@ -52,19 +52,22 @@ class NearestGCRoot {
     private static final String SVM_REFFERENCE = "com.oracle.svm.core.heap.heapImpl.DiscoverableReference";    // NOI18N
     private static final String SVM_REFFERENCE_1 = "com.oracle.svm.core.heap.DiscoverableReference";    // NOI18N
     private static final String SVM_REFERENT_FIELD_NAME = "rawReferent"; // NOI18N
+    private static final int DEEP_LEVEL = 10000;
 
     //~ Instance fields ----------------------------------------------------------------------------------------------------------
 
     private Field referentField;
     private HprofHeap heap;
     private LongBuffer readBuffer;
     private LongBuffer writeBuffer;
+    private LongBuffer deepPathBuffer;
     private LongBuffer leaves;
     private LongBuffer multipleParents;
     private Set<JavaClass> referenceClasses;
     private boolean gcRootsComputed;
     private long allInstances;
     private long processedInstances;
+    private long level;
 //private long leavesCount;
 //private long firstLevel;
 //private long multiParentsCount;
@@ -160,6 +163,7 @@ private boolean initSVMReference() {
 
     private void computeOneLevel(Set<JavaClass> processedClasses) throws IOException {
         int idSize = heap.dumpBuffer.getIDSize();
+        level++;
         for (;;) {
             Instance instance;
             long instanceOffset = readLong();
@@ -250,6 +254,7 @@ private void createBuffers() {
         writeBuffer = new LongBuffer(BUFFER_SIZE, heap.cacheDirectory);
         leaves = new LongBuffer(BUFFER_SIZE, heap.cacheDirectory);
         multipleParents = new LongBuffer(BUFFER_SIZE, heap.cacheDirectory);
+        deepPathBuffer = new LongBuffer(BUFFER_SIZE, heap.cacheDirectory);
     }
 
     private void deleteBuffers() {
@@ -309,6 +314,10 @@ private boolean writeConnection(long instanceId, long refInstanceId, boolean add
 
             if (entry != null && entry.getNearestGCRootPointer() == 0L && heap.gcRoots.getGCRoots(refInstanceId) == null) {
                 writeLong(entry.getOffset());
+                if (level > DEEP_LEVEL) {
+                    deepPathBuffer.writeLong(refInstanceId);
+                    entry.setDeepObj();
+                }
                 if (addRefInstanceId) {
                     if (!checkReferences(refInstanceId, instanceId)) {
                         entry.addReference(instanceId);
@@ -379,12 +388,18 @@ LongBuffer getMultipleParents() {
         return multipleParents;
     }
 
+    LongBuffer getDeepPathBuffer() {
+        computeGCRoots();
+        return deepPathBuffer;
+    }
+
     //---- Serialization support
     void writeToStream(DataOutputStream out) throws IOException {
         out.writeBoolean(gcRootsComputed);
         if (gcRootsComputed) {
             leaves.writeToStream(out);
             multipleParents.writeToStream(out);
+            deepPathBuffer.writeToStream(out);
         }
     }
 
@@ -394,6 +409,7 @@ void writeToStream(DataOutputStream out) throws IOException {
         if (gcRootsComputed) {
             leaves = new LongBuffer(dis, heap.cacheDirectory);
             multipleParents = new LongBuffer(dis, heap.cacheDirectory);
+            deepPathBuffer = new LongBuffer(dis, heap.cacheDirectory);
         }
     }
 }