6815790: G1: Missing MemoryPoolMXBeans with -XX:+UseG1GC

It introduces the necessary memory pools for G1.

Reviewed-by: mchung, ysr

hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp

@@ -928,6 +928,8 @@ void G1CollectedHeap::do_collection(bool full, bool clear_all_soft_refs,
     TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty);
     TraceTime t(full ? "Full GC (System.gc())" : "Full GC", PrintGC, true, gclog_or_tty);
 
+    TraceMemoryManagerStats tms(true /* fullGC */);
+
     double start = os::elapsedTime();
     g1_policy()->record_full_collection_start();
 
@@ -1001,6 +1003,8 @@ void G1CollectedHeap::do_collection(bool full, bool clear_all_soft_refs,
 
     COMPILER2_PRESENT(DerivedPointerTable::update_pointers());
 
+    MemoryService::track_memory_usage();
+
     if (VerifyAfterGC && total_collections() >= VerifyGCStartAt) {
       HandleMark hm;  // Discard invalid handles created during verification
       gclog_or_tty->print(" VerifyAfterGC:");
@@ -2645,6 +2649,8 @@ G1CollectedHeap::do_collection_pause_at_safepoint() {
   }
 
   {
+    ResourceMark rm;
+
     char verbose_str[128];
     sprintf(verbose_str, "GC pause ");
     if (g1_policy()->in_young_gc_mode()) {
@@ -2663,7 +2669,8 @@ G1CollectedHeap::do_collection_pause_at_safepoint() {
     TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty);
     TraceTime t(verbose_str, PrintGC && !PrintGCDetails, true, gclog_or_tty);
 
-    ResourceMark rm;
+    TraceMemoryManagerStats tms(false /* fullGC */);
+
     assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
     assert(Thread::current() == VMThread::vm_thread(), "should be in vm thread");
     guarantee(!is_gc_active(), "collection is not reentrant");
@@ -2859,6 +2866,8 @@ G1CollectedHeap::do_collection_pause_at_safepoint() {
 
       assert(regions_accounted_for(), "Region leakage.");
 
+      MemoryService::track_memory_usage();
+
       if (VerifyAfterGC && total_collections() >= VerifyGCStartAt) {
         HandleMark hm;  // Discard invalid handles created during verification
         gclog_or_tty->print(" VerifyAfterGC:");

hotspot/src/share/vm/gc_implementation/includeDB_gc_g1

@@ -222,6 +222,15 @@ g1MarkSweep.hpp                         oop.hpp
 g1MarkSweep.hpp                         timer.hpp
 g1MarkSweep.hpp                         universe.hpp
 
+g1MemoryPool.cpp                        heapRegion.hpp
+g1MemoryPool.cpp                        g1CollectedHeap.inline.hpp
+g1MemoryPool.cpp                        g1CollectedHeap.hpp
+g1MemoryPool.cpp                        g1CollectorPolicy.hpp
+g1MemoryPool.cpp                        g1MemoryPool.hpp
+
+g1MemoryPool.hpp                        memoryUsage.hpp
+g1MemoryPool.hpp                        memoryPool.hpp
+
 g1OopClosures.inline.hpp		concurrentMark.hpp
 g1OopClosures.inline.hpp		g1OopClosures.hpp
 g1OopClosures.inline.hpp		g1CollectedHeap.hpp
@@ -303,6 +312,8 @@ heapRegionSeq.inline.hpp                heapRegionSeq.hpp
 
 klass.hpp				g1OopClosures.hpp
 
+memoryService.cpp                       g1MemoryPool.hpp
+
 ptrQueue.cpp                            allocation.hpp
 ptrQueue.cpp                            allocation.inline.hpp
 ptrQueue.cpp                            mutex.hpp

hotspot/src/share/vm/services/g1MemoryPool.cpp

@@ -0,0 +1,153 @@
+/*
+ * Copyright (c) 2007 Sun Microsystems, Inc.  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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_g1MemoryPool.cpp.incl"
+
+G1MemoryPoolSuper::G1MemoryPoolSuper(G1CollectedHeap* g1h,
+                                     const char* name,
+                                     size_t init_size,
+                                     size_t max_size,
+                                     bool support_usage_threshold) :
+  _g1h(g1h), CollectedMemoryPool(name,
+                                 MemoryPool::Heap,
+                                 init_size,
+                                 max_size,
+                                 support_usage_threshold) {
+  assert(UseG1GC, "sanity");
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::eden_space_committed(G1CollectedHeap* g1h) {
+  return eden_space_used(g1h);
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::eden_space_used(G1CollectedHeap* g1h) {
+  size_t young_list_length = g1h->young_list_length();
+  size_t eden_used = young_list_length * HeapRegion::GrainBytes;
+  size_t survivor_used = survivor_space_used(g1h);
+  eden_used = subtract_up_to_zero(eden_used, survivor_used);
+  return eden_used;
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::eden_space_max(G1CollectedHeap* g1h) {
+  return eden_space_committed(g1h);
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::survivor_space_committed(G1CollectedHeap* g1h) {
+  return survivor_space_used(g1h);
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::survivor_space_used(G1CollectedHeap* g1h) {
+  size_t survivor_num = g1h->g1_policy()->recorded_survivor_regions();
+  size_t survivor_used = survivor_num * HeapRegion::GrainBytes;
+  return survivor_used;
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::survivor_space_max(G1CollectedHeap* g1h) {
+  return survivor_space_committed(g1h);
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::old_space_committed(G1CollectedHeap* g1h) {
+  size_t committed = overall_committed(g1h);
+  size_t eden_committed = eden_space_committed(g1h);
+  size_t survivor_committed = survivor_space_committed(g1h);
+  committed = subtract_up_to_zero(committed, eden_committed);
+  committed = subtract_up_to_zero(committed, survivor_committed);
+  return committed;
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::old_space_used(G1CollectedHeap* g1h) {
+  size_t used = overall_used(g1h);
+  size_t eden_used = eden_space_used(g1h);
+  size_t survivor_used = survivor_space_used(g1h);
+  used = subtract_up_to_zero(used, eden_used);
+  used = subtract_up_to_zero(used, survivor_used);
+  return used;
+}
+
+// See the comment at the top of g1MemoryPool.hpp
+size_t G1MemoryPoolSuper::old_space_max(G1CollectedHeap* g1h) {
+  size_t max = g1h->g1_reserved_obj_bytes();
+  size_t eden_max = eden_space_max(g1h);
+  size_t survivor_max = survivor_space_max(g1h);
+  max = subtract_up_to_zero(max, eden_max);
+  max = subtract_up_to_zero(max, survivor_max);
+  return max;
+}
+
+G1EdenPool::G1EdenPool(G1CollectedHeap* g1h) :
+  G1MemoryPoolSuper(g1h,
+                    "G1 Eden",
+                    eden_space_committed(g1h), /* init_size */
+                    eden_space_max(g1h), /* max_size */
+                    false /* support_usage_threshold */) {
+}
+
+MemoryUsage G1EdenPool::get_memory_usage() {
+  size_t maxSize   = max_size();
+  size_t used      = used_in_bytes();
+  size_t committed = eden_space_committed();
+
+  return MemoryUsage(initial_size(), used, committed, maxSize);
+}
+
+G1SurvivorPool::G1SurvivorPool(G1CollectedHeap* g1h) :
+  G1MemoryPoolSuper(g1h,
+                    "G1 Survivor",
+                    survivor_space_committed(g1h), /* init_size */
+                    survivor_space_max(g1h), /* max_size */
+                    false /* support_usage_threshold */) {
+}
+
+MemoryUsage G1SurvivorPool::get_memory_usage() {
+  size_t maxSize   = max_size();
+  size_t used      = used_in_bytes();
+  size_t committed = survivor_space_committed();
+
+  return MemoryUsage(initial_size(), used, committed, maxSize);
+}
+
+G1OldGenPool::G1OldGenPool(G1CollectedHeap* g1h) :
+  G1MemoryPoolSuper(g1h,
+                    "G1 Old Gen",
+                    old_space_committed(g1h), /* init_size */
+                    old_space_max(g1h), /* max_size */
+                    true /* support_usage_threshold */) {
+}
+
+MemoryUsage G1OldGenPool::get_memory_usage() {
+  size_t maxSize   = max_size();
+  size_t used      = used_in_bytes();
+  size_t committed = old_space_committed();
+
+  return MemoryUsage(initial_size(), used, committed, maxSize);
+}

hotspot/src/share/vm/services/g1MemoryPool.hpp

@@ -0,0 +1,226 @@
+/*
+ * Copyright (c) 2007 Sun Microsystems, Inc.  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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+class G1CollectedHeap;
+
+// This file contains the three classes that represent the memory
+// pools of the G1 spaces: G1EdenPool, G1SurvivorPool, and
+// G1OldGenPool. In G1, unlike our other GCs, we do not have a
+// physical space for each of those spaces. Instead, we allocate
+// regions for all three spaces out of a single pool of regions (that
+// pool basically covers the entire heap). As a result, the eden,
+// survivor, and old gen are considered logical spaces in G1, as each
+// is a set of non-contiguous regions. This is also reflected in the
+// way we map them to memory pools here. The easiest way to have done
+// this would have been to map the entire G1 heap to a single memory
+// pool. However, it's helpful to show how large the eden and survivor
+// get, as this does affect the performance and behavior of G1. Which
+// is why we introduce the three memory pools implemented here.
+//
+// The above approach inroduces a couple of challenging issues in the
+// implementation of the three memory pools:
+//
+// 1) The used space calculation for a pool is not necessarily
+// independent of the others. We can easily get from G1 the overall
+// used space in the entire heap, the number of regions in the young
+// generation (includes both eden and survivors), and the number of
+// survivor regions. So, from that we calculate:
+//
+//  survivor_used = survivor_num * region_size
+//  eden_used     = young_region_num * region_size - survivor_used
+//  old_gen_used  = overall_used - eden_used - survivor_used
+//
+// Note that survivor_used and eden_used are upper bounds. To get the
+// actual value we would have to iterate over the regions and add up
+// ->used(). But that'd be expensive. So, we'll accept some lack of
+// accuracy for those two. But, we have to be careful when calculating
+// old_gen_used, in case we subtract from overall_used more then the
+// actual number and our result goes negative.
+//
+// 2) Calculating the used space is straightforward, as described
+// above. However, how do we calculate the committed space, given that
+// we allocate space for the eden, survivor, and old gen out of the
+// same pool of regions? One way to do this is to use the used value
+// as also the committed value for the eden and survivor spaces and
+// then calculate the old gen committed space as follows:
+//
+//  old_gen_committed = overall_committed - eden_committed - survivor_committed
+//
+// Maybe a better way to do that would be to calculate used for eden
+// and survivor as a sum of ->used() over their regions and then
+// calculate committed as region_num * region_size (i.e., what we use
+// to calculate the used space now). This is something to consider
+// in the future.
+//
+// 3) Another decision that is again not straightforward is what is
+// the max size that each memory pool can grow to. Right now, we set
+// that the committed size for the eden and the survivors and
+// calculate the old gen max as follows (basically, it's a similar
+// pattern to what we use for the committed space, as described
+// above):
+//
+//  old_gen_max = overall_max - eden_max - survivor_max
+//
+// 4) Now, there is a very subtle issue with all the above. The
+// framework will call get_memory_usage() on the three pools
+// asynchronously. As a result, each call might get a different value
+// for, say, survivor_num which will yield inconsistent values for
+// eden_used, survivor_used, and old_gen_used (as survivor_num is used
+// in the calculation of all three). This would normally be
+// ok. However, it's possible that this might cause the sum of
+// eden_used, survivor_used, and old_gen_used to go over the max heap
+// size and this seems to sometimes cause JConsole (and maybe other
+// clients) to get confused. There's not a really an easy / clean
+// solution to this problem, due to the asynchrounous nature of the
+// framework.
+
+
+// This class is shared by the three G1 memory pool classes
+// (G1EdenPool, G1SurvivorPool, G1OldGenPool). Given that the way we
+// calculate used / committed bytes for these three pools is related
+// (see comment above), we put the calculations in this class so that
+// we can easily share them among the subclasses.
+class G1MemoryPoolSuper : public CollectedMemoryPool {
+private:
+  G1CollectedHeap* _g1h;
+
+  // It returns x - y if x > y, 0 otherwise.
+  // As described in the comment above, some of the inputs to the
+  // calculations we have to do are obtained concurrently and hence
+  // may be inconsistent with each other. So, this provides a
+  // defensive way of performing the subtraction and avoids the value
+  // going negative (which would mean a very large result, given that
+  // the parameter are size_t).
+  static size_t subtract_up_to_zero(size_t x, size_t y) {
+    if (x > y) {
+      return x - y;
+    } else {
+      return 0;
+    }
+  }
+
+protected:
+  // Would only be called from subclasses.
+  G1MemoryPoolSuper(G1CollectedHeap* g1h,
+                    const char* name,
+                    size_t init_size,
+                    size_t max_size,
+                    bool support_usage_threshold);
+
+  // The reason why all the code is in static methods is so that it
+  // can be safely called from the constructors of the subclasses.
+
+  static size_t overall_committed(G1CollectedHeap* g1h) {
+    return g1h->capacity();
+  }
+  static size_t overall_used(G1CollectedHeap* g1h) {
+    return g1h->used_unlocked();
+  }
+
+  static size_t eden_space_committed(G1CollectedHeap* g1h);
+  static size_t eden_space_used(G1CollectedHeap* g1h);
+  static size_t eden_space_max(G1CollectedHeap* g1h);
+
+  static size_t survivor_space_committed(G1CollectedHeap* g1h);
+  static size_t survivor_space_used(G1CollectedHeap* g1h);
+  static size_t survivor_space_max(G1CollectedHeap* g1h);
+
+  static size_t old_space_committed(G1CollectedHeap* g1h);
+  static size_t old_space_used(G1CollectedHeap* g1h);
+  static size_t old_space_max(G1CollectedHeap* g1h);
+
+  // The non-static versions are included for convenience.
+
+  size_t eden_space_committed() {
+    return eden_space_committed(_g1h);
+  }
+  size_t eden_space_used() {
+    return eden_space_used(_g1h);
+  }
+  size_t eden_space_max() {
+    return eden_space_max(_g1h);
+  }
+
+  size_t survivor_space_committed() {
+    return survivor_space_committed(_g1h);
+  }
+  size_t survivor_space_used() {
+    return survivor_space_used(_g1h);
+  }
+  size_t survivor_space_max() {
+    return survivor_space_max(_g1h);
+  }
+
+  size_t old_space_committed() {
+    return old_space_committed(_g1h);
+  }
+  size_t old_space_used() {
+    return old_space_used(_g1h);
+  }
+  size_t old_space_max() {
+    return old_space_max(_g1h);
+  }
+};
+
+// Memory pool that represents the G1 eden.
+class G1EdenPool : public G1MemoryPoolSuper {
+public:
+  G1EdenPool(G1CollectedHeap* g1h);
+
+  size_t used_in_bytes() {
+    return eden_space_used();
+  }
+  size_t max_size() {
+    return eden_space_max();
+  }
+  MemoryUsage get_memory_usage();
+};
+
+// Memory pool that represents the G1 survivor.
+class G1SurvivorPool : public G1MemoryPoolSuper {
+public:
+  G1SurvivorPool(G1CollectedHeap* g1h);
+
+  size_t used_in_bytes() {
+    return survivor_space_used();
+  }
+  size_t max_size() {
+    return survivor_space_max();
+  }
+  MemoryUsage get_memory_usage();
+};
+
+// Memory pool that represents the G1 old gen.
+class G1OldGenPool : public G1MemoryPoolSuper {
+public:
+  G1OldGenPool(G1CollectedHeap* g1h);
+
+  size_t used_in_bytes() {
+    return old_space_used();
+  }
+  size_t max_size() {
+    return old_space_max();
+  }
+  MemoryUsage get_memory_usage();
+};

hotspot/src/share/vm/services/memoryManager.cpp

@@ -72,6 +72,14 @@ GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() {
   return (GCMemoryManager*) new PSMarkSweepMemoryManager();
 }
 
+GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() {
+  return (GCMemoryManager*) new G1YoungGenMemoryManager();
+}
+
+GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() {
+  return (GCMemoryManager*) new G1OldGenMemoryManager();
+}
+
 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
   // Must do an acquire so as to force ordering of subsequent
   // loads from anything _memory_mgr_obj points to or implies.

hotspot/src/share/vm/services/memoryManager.hpp

@@ -54,7 +54,9 @@ public:
     ParNew,
     ConcurrentMarkSweep,
     PSScavenge,
-    PSMarkSweep
+    PSMarkSweep,
+    G1YoungGen,
+    G1OldGen
   };
 
   MemoryManager();
@@ -85,6 +87,8 @@ public:
   static GCMemoryManager* get_cms_memory_manager();
   static GCMemoryManager* get_psScavenge_memory_manager();
   static GCMemoryManager* get_psMarkSweep_memory_manager();
+  static GCMemoryManager* get_g1YoungGen_memory_manager();
+  static GCMemoryManager* get_g1OldGen_memory_manager();
 
 };
 
@@ -231,3 +235,21 @@ public:
   MemoryManager::Name kind() { return MemoryManager::PSMarkSweep; }
   const char* name()         { return "PS MarkSweep"; }
 };
+
+class G1YoungGenMemoryManager : public GCMemoryManager {
+private:
+public:
+  G1YoungGenMemoryManager() : GCMemoryManager() {}
+
+  MemoryManager::Name kind() { return MemoryManager::G1YoungGen; }
+  const char* name()         { return "G1 Young Generation"; }
+};
+
+class G1OldGenMemoryManager : public GCMemoryManager {
+private:
+public:
+  G1OldGenMemoryManager() : GCMemoryManager() {}
+
+  MemoryManager::Name kind() { return MemoryManager::G1OldGen; }
+  const char* name()         { return "G1 Old Generation"; }
+};

hotspot/src/share/vm/services/memoryService.cpp

@@ -60,8 +60,8 @@ void MemoryService::set_universe_heap(CollectedHeap* heap) {
       break;
     }
     case CollectedHeap::G1CollectedHeap : {
-      G1CollectedHeap::g1_unimplemented();
-      return;
+      add_g1_heap_info(G1CollectedHeap::heap());
+      break;
     }
 #endif // SERIALGC
     default: {
@@ -164,6 +164,19 @@ void MemoryService::add_parallel_scavenge_heap_info(ParallelScavengeHeap* heap)
   add_psOld_memory_pool(heap->old_gen(), _major_gc_manager);
   add_psPerm_memory_pool(heap->perm_gen(), _major_gc_manager);
 }
+
+void MemoryService::add_g1_heap_info(G1CollectedHeap* g1h) {
+  assert(UseG1GC, "sanity");
+
+  _minor_gc_manager = MemoryManager::get_g1YoungGen_memory_manager();
+  _major_gc_manager = MemoryManager::get_g1OldGen_memory_manager();
+  _managers_list->append(_minor_gc_manager);
+  _managers_list->append(_major_gc_manager);
+
+  add_g1YoungGen_memory_pool(g1h, _major_gc_manager, _minor_gc_manager);
+  add_g1OldGen_memory_pool(g1h, _major_gc_manager);
+  add_g1PermGen_memory_pool(g1h, _major_gc_manager);
+}
 #endif // SERIALGC
 
 MemoryPool* MemoryService::add_gen(Generation* gen,
@@ -384,6 +397,64 @@ void MemoryService::add_psPerm_memory_pool(PSPermGen* gen, MemoryManager* mgr) {
   mgr->add_pool(perm_gen);
   _pools_list->append(perm_gen);
 }
+
+void MemoryService::add_g1YoungGen_memory_pool(G1CollectedHeap* g1h,
+                                               MemoryManager* major_mgr,
+                                               MemoryManager* minor_mgr) {
+  assert(major_mgr != NULL && minor_mgr != NULL, "should have two managers");
+
+  G1EdenPool* eden = new G1EdenPool(g1h);
+  G1SurvivorPool* survivor = new G1SurvivorPool(g1h);
+
+  major_mgr->add_pool(eden);
+  major_mgr->add_pool(survivor);
+  minor_mgr->add_pool(eden);
+  minor_mgr->add_pool(survivor);
+  _pools_list->append(eden);
+  _pools_list->append(survivor);
+}
+
+void MemoryService::add_g1OldGen_memory_pool(G1CollectedHeap* g1h,
+                                             MemoryManager* mgr) {
+  assert(mgr != NULL, "should have one manager");
+
+  G1OldGenPool* old_gen = new G1OldGenPool(g1h);
+  mgr->add_pool(old_gen);
+  _pools_list->append(old_gen);
+}
+
+void MemoryService::add_g1PermGen_memory_pool(G1CollectedHeap* g1h,
+                                              MemoryManager* mgr) {
+  assert(mgr != NULL, "should have one manager");
+
+  CompactingPermGenGen* perm_gen = (CompactingPermGenGen*) g1h->perm_gen();
+  PermanentGenerationSpec* spec = perm_gen->spec();
+  size_t max_size = spec->max_size() - spec->read_only_size()
+                                     - spec->read_write_size();
+  MemoryPool* pool = add_space(perm_gen->unshared_space(),
+                               "G1 Perm Gen",
+                               false, /* is_heap */
+                               max_size,
+                               true   /* support_usage_threshold */);
+  mgr->add_pool(pool);
+
+  // in case we support CDS in G1
+  if (UseSharedSpaces) {
+    pool = add_space(perm_gen->ro_space(),
+                     "G1 Perm Gen [shared-ro]",
+                     false, /* is_heap */
+                     spec->read_only_size(),
+                     true   /* support_usage_threshold */);
+    mgr->add_pool(pool);
+
+    pool = add_space(perm_gen->rw_space(),
+                     "G1 Perm Gen [shared-rw]",
+                     false, /* is_heap */
+                     spec->read_write_size(),
+                     true   /* support_usage_threshold */);
+    mgr->add_pool(pool);
+  }
+}
 #endif // SERIALGC
 
 void MemoryService::add_code_heap_memory_pool(CodeHeap* heap) {

hotspot/src/share/vm/services/memoryService.hpp

@@ -40,6 +40,7 @@ class GenCollectedHeap;
 class ParallelScavengeHeap;
 class CompactingPermGenGen;
 class CMSPermGenGen;
+class G1CollectedHeap;
 
 // VM Monitoring and Management Support
 
@@ -88,6 +89,13 @@ private:
   static void add_psPerm_memory_pool(PSPermGen* perm,
                                      MemoryManager* mgr);
 
+  static void add_g1YoungGen_memory_pool(G1CollectedHeap* g1h,
+                                         MemoryManager* major_mgr,
+                                         MemoryManager* minor_mgr);
+  static void add_g1OldGen_memory_pool(G1CollectedHeap* g1h,
+                                       MemoryManager* mgr);
+  static void add_g1PermGen_memory_pool(G1CollectedHeap* g1h,
+                                        MemoryManager* mgr);
 
   static MemoryPool* add_space(ContiguousSpace* space,
                                const char* name,
@@ -111,6 +119,7 @@ private:
 
   static void add_gen_collected_heap_info(GenCollectedHeap* heap);
   static void add_parallel_scavenge_heap_info(ParallelScavengeHeap* heap);
+  static void add_g1_heap_info(G1CollectedHeap* g1h);
 
 public:
   static void set_universe_heap(CollectedHeap* heap);