--- a/hotspot/test/serviceability/tmtools/jstat/GcCapacityTest.java	Mon Nov 21 21:07:45 2016 -0500
+++ b/hotspot/test/serviceability/tmtools/jstat/GcCapacityTest.java	Tue Nov 22 16:13:13 2016 +0300
@@ -45,7 +45,7 @@
         measurement1.assertConsistency();
 
         // Provoke a gc and verify the changed values
-        GcProvoker gcProvoker = GcProvoker.createGcProvoker();
+        GcProvoker gcProvoker = new GcProvoker();
         gcProvoker.provokeGc();
         JstatGcCapacityResults measurement2 = jstatGcTool.measure();
         measurement2.assertConsistency();

--- a/hotspot/test/serviceability/tmtools/jstat/GcCauseTest01.java	Mon Nov 21 21:07:45 2016 -0500
+++ b/hotspot/test/serviceability/tmtools/jstat/GcCauseTest01.java	Tue Nov 22 16:13:13 2016 +0300
@@ -47,7 +47,7 @@
         JstatGcCauseResults measurement1 = jstatGcTool.measure();
         measurement1.assertConsistency();
 
-        GcProvoker gcProvoker = GcProvoker.createGcProvoker();
+        GcProvoker gcProvoker = new GcProvoker();
 
         // Provoke GC then run the tool again and get the results  asserting that they are reasonable
         gcProvoker.provokeGc();

--- a/hotspot/test/serviceability/tmtools/jstat/GcCauseTest02.java	Mon Nov 21 21:07:45 2016 -0500
+++ b/hotspot/test/serviceability/tmtools/jstat/GcCauseTest02.java	Tue Nov 22 16:13:13 2016 +0300
@@ -27,11 +27,11 @@
  *          Test scenario:
  *          tests forces debuggee application eat ~70% of heap and runs jstat.
  *          jstat should show that ~70% of heap (OC/OU ~= 70%).
+ * @requires vm.opt.ExplicitGCInvokesConcurrent != true
  * @modules java.base/jdk.internal.misc
  * @library /test/lib
  * @library ../share
- * @ignore 8168396
- * @run main/othervm -XX:+UsePerfData -Xmx128M -XX:MaxMetaspaceSize=128M GcCauseTest02
+ * @run main/othervm -XX:+UsePerfData -XX:InitialHeapSize=128M -XX:MaxHeapSize=128M -XX:MaxMetaspaceSize=128M GcCauseTest02
  */
 import utils.*;
 
@@ -48,10 +48,12 @@
         JstatGcCauseResults measurement1 = jstatGcTool.measure();
         measurement1.assertConsistency();
 
-        GcProvoker gcProvoker = GcProvoker.createGcProvoker();
+        GcProvoker gcProvoker = new GcProvoker();
 
         // Eat metaspace and heap then run the tool again and get the results  asserting that they are reasonable
-        gcProvoker.eatMetaspaceAndHeap(targetMemoryUsagePercent);
+        gcProvoker.allocateAvailableMetaspaceAndHeap(targetMemoryUsagePercent);
+        // Collect garbage. Also update VM statistics
+        System.gc();
         JstatGcCauseResults measurement2 = jstatGcTool.measure();
         measurement2.assertConsistency();
 

--- a/hotspot/test/serviceability/tmtools/jstat/GcNewTest.java	Mon Nov 21 21:07:45 2016 -0500
+++ b/hotspot/test/serviceability/tmtools/jstat/GcNewTest.java	Tue Nov 22 16:13:13 2016 +0300
@@ -46,7 +46,7 @@
         JstatGcNewResults measurement1 = jstatGcTool.measure();
         measurement1.assertConsistency();
 
-        GcProvoker gcProvoker = GcProvoker.createGcProvoker();
+        GcProvoker gcProvoker = new GcProvoker();
 
         // Provoke GC and run the tool again
         gcProvoker.provokeGc();

--- a/hotspot/test/serviceability/tmtools/jstat/GcTest01.java	Mon Nov 21 21:07:45 2016 -0500
+++ b/hotspot/test/serviceability/tmtools/jstat/GcTest01.java	Tue Nov 22 16:13:13 2016 +0300
@@ -50,7 +50,7 @@
         JstatGcResults measurement1 = jstatGcTool.measure();
         measurement1.assertConsistency();
 
-        GcProvoker gcProvoker = GcProvoker.createGcProvoker();
+        GcProvoker gcProvoker = new GcProvoker();
 
         // Provoke GC then run the tool again and get the results
         // asserting that they are reasonable

--- a/hotspot/test/serviceability/tmtools/jstat/GcTest02.java	Mon Nov 21 21:07:45 2016 -0500
+++ b/hotspot/test/serviceability/tmtools/jstat/GcTest02.java	Tue Nov 22 16:13:13 2016 +0300
@@ -28,11 +28,11 @@
  *          Test scenario:
  *          tests forces debuggee application eat ~70% of heap and runs jstat.
  *          jstat should show that ~70% of heap is utilized (OC/OU ~= 70%).
+ * @requires vm.opt.ExplicitGCInvokesConcurrent != true
  * @modules java.base/jdk.internal.misc
  * @library /test/lib
  * @library ../share
- * @ignore 8168396
- * @run main/othervm -XX:+UsePerfData -Xmx128M -XX:MaxMetaspaceSize=128M GcTest02
+ * @run main/othervm -XX:+UsePerfData -XX:InitialHeapSize=128M -XX:MaxHeapSize=128M -XX:MaxMetaspaceSize=128M GcTest02
  */
 
 public class GcTest02 {
@@ -48,10 +48,12 @@
         JstatGcResults measurement1 = jstatGcTool.measure();
         measurement1.assertConsistency();
 
-        GcProvoker gcProvoker = GcProvoker.createGcProvoker();
+        GcProvoker gcProvoker = new GcProvoker();
 
         // Eat metaspace and heap then run the tool again and get the results  asserting that they are reasonable
-        gcProvoker.eatMetaspaceAndHeap(targetMemoryUsagePercent);
+        gcProvoker.allocateAvailableMetaspaceAndHeap(targetMemoryUsagePercent);
+        // Collect garbage. Also updates VM statistics
+        System.gc();
         JstatGcResults measurement2 = jstatGcTool.measure();
         measurement2.assertConsistency();
 

--- a/hotspot/test/serviceability/tmtools/jstat/utils/GcProvoker.java	Mon Nov 21 21:07:45 2016 -0500
+++ b/hotspot/test/serviceability/tmtools/jstat/utils/GcProvoker.java	Tue Nov 22 16:13:13 2016 +0300
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,34 +22,136 @@
  */
 package utils;
 
+import java.lang.management.ManagementFactory;
+import java.lang.management.MemoryPoolMXBean;
+import java.lang.management.MemoryUsage;
+import java.util.ArrayList;
+import java.util.List;
+
 /**
- * This is an interface used to provoke GC and perform other GC-related
+ * This is an class used to provoke GC and perform other GC-related
  * procedures
  *
  */
-public interface GcProvoker {
+public class GcProvoker{
+
+    // Uses fixed small objects to avoid Humongous objects allocation in G1
+    public static final int MEMORY_CHUNK = 2048;
+    public static final float ALLOCATION_TOLERANCE = 0.05f;
+
+    public static List<Object> allocatedMetaspace;
+    public static List<Object> allocatedMemory;
+
+    private final Runtime runtime;
 
-    /**
-     * The default implementation
-     *
-     * @return the default GC provoker
-     */
-    public static GcProvoker createGcProvoker() {
-        return new GcProvokerImpl();
+    private List<Object> allocateHeap(float targetUsage) {
+        long maxMemory = runtime.maxMemory();
+        List<Object> list = new ArrayList<>();
+        long used = 0;
+        long target = (long) (maxMemory * targetUsage);
+        while (used < target) {
+            try {
+                list.add(new byte[MEMORY_CHUNK]);
+                used += MEMORY_CHUNK;
+            } catch (OutOfMemoryError e) {
+                list = null;
+                throw new RuntimeException("Unexpected OOME '" + e.getMessage() + "' while eating " + targetUsage + " of heap memory.");
+            }
+        }
+        return list;
+    }
+
+    private List<Object> allocateAvailableHeap(float targetUsage) {
+        // Calculates size of free memory after allocation with small tolerance.
+        long minFreeMemory = (long) ((1.0 - (targetUsage + ALLOCATION_TOLERANCE)) * runtime.maxMemory());
+        List<Object> list = new ArrayList<>();
+        do {
+            try {
+                list.add(new byte[MEMORY_CHUNK]);
+            } catch (OutOfMemoryError e) {
+                list = null;
+                throw new RuntimeException("Unexpected OOME '" + e.getMessage() + "' while eating " + targetUsage + " of heap memory.");
+            }
+        } while (runtime.freeMemory() > minFreeMemory);
+        return list;
     }
 
     /**
      * This method provokes a GC
      */
-    public void provokeGc();
+    public void provokeGc() {
+        for (int i = 0; i < 3; i++) {
+            long edenSize = Pools.getEdenCommittedSize();
+            long heapSize = Pools.getHeapCommittedSize();
+            float targetPercent = ((float) edenSize) / (heapSize);
+            if ((targetPercent < 0) || (targetPercent > 1.0)) {
+                throw new RuntimeException("Error in the percent calculation" + " (eden size: " + edenSize + ", heap size: " + heapSize + ", calculated eden percent: " + targetPercent + ")");
+            }
+            allocateHeap(targetPercent);
+            allocateHeap(targetPercent);
+            System.gc();
+        }
+    }
+
+    /**
+     * Allocates heap and metaspace upon exit not less than targetMemoryUsagePercent percents
+     * of heap and metaspace have been consumed.
+     *
+     * @param targetMemoryUsagePercent how many percent of heap and metaspace to
+     * allocate
+     */
+
+    public void allocateMetaspaceAndHeap(float targetMemoryUsagePercent) {
+        // Metaspace should be filled before Java Heap to prevent unexpected OOME
+        // in the Java Heap while filling Metaspace
+        allocatedMetaspace = eatMetaspace(targetMemoryUsagePercent);
+        allocatedMemory = allocateHeap(targetMemoryUsagePercent);
+    }
 
     /**
-     * Eats heap and metaspace Upon exit targetMemoryUsagePercent percents of
-     * heap and metaspace is have been eaten
+     * Allocates heap and metaspace upon exit targetMemoryUsagePercent percents
+     * of heap and metaspace have been consumed.
      *
      * @param targetMemoryUsagePercent how many percent of heap and metaspace to
-     * eat
+     * allocate
      */
-    public void eatMetaspaceAndHeap(float targetMemoryUsagePercent);
+    public void allocateAvailableMetaspaceAndHeap(float targetMemoryUsagePercent) {
+        // Metaspace should be filled before Java Heap to prevent unexpected OOME
+        // in the Java Heap while filling Metaspace
+        allocatedMetaspace = eatMetaspace(targetMemoryUsagePercent);
+        allocatedMemory = allocateAvailableHeap(targetMemoryUsagePercent);
+    }
+
+    private List<Object> eatMetaspace(float targetUsage) {
+        List<Object> list = new ArrayList<>();
+        final String metaspacePoolName = "Metaspace";
+        MemoryPoolMXBean metaspacePool = null;
+        for (MemoryPoolMXBean pool : ManagementFactory.getMemoryPoolMXBeans()) {
+            if (pool.getName().contains(metaspacePoolName)) {
+                metaspacePool = pool;
+                break;
+            }
+        }
+        if (metaspacePool == null) {
+            throw new RuntimeException("MXBean for Metaspace pool wasn't found");
+        }
+        float currentUsage;
+        GeneratedClassProducer gp = new GeneratedClassProducer();
+        do {
+            try {
+                list.add(gp.create(0));
+            } catch (OutOfMemoryError oome) {
+                list = null;
+                throw new RuntimeException("Unexpected OOME '" + oome.getMessage() + "' while eating " + targetUsage + " of Metaspace.");
+            }
+            MemoryUsage memoryUsage = metaspacePool.getUsage();
+            currentUsage = (((float) memoryUsage.getUsed()) / memoryUsage.getMax());
+        } while (currentUsage < targetUsage);
+        return list;
+    }
+
+    public GcProvoker() {
+        runtime = Runtime.getRuntime();
+    }
 
 }