1 /*
   2  * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_SERVICES_MEMORYMANAGER_HPP
  26 #define SHARE_VM_SERVICES_MEMORYMANAGER_HPP
  27 
  28 #include "gc/shared/gcCause.hpp"
  29 #include "memory/allocation.hpp"
  30 #include "runtime/handles.hpp"
  31 #include "runtime/timer.hpp"
  32 #include "oops/instanceOop.hpp"
  33 #include "services/memoryUsage.hpp"
  34 
  35 // A memory manager is responsible for managing one or more memory pools.
  36 // The garbage collector is one type of memory managers responsible
  37 // for reclaiming memory occupied by unreachable objects.  A Java virtual
  38 // machine may have one or more memory managers.   It may
  39 // add or remove memory managers during execution.
  40 // A memory pool can be managed by more than one memory managers.
  41 
  42 class MemoryPool;
  43 class GCMemoryManager;
  44 class OopClosure;
  45 
  46 class MemoryManager : public CHeapObj<mtInternal> {
  47 private:
  48   enum {
  49     max_num_pools = 10
  50   };
  51 
  52   MemoryPool* _pools[max_num_pools];
  53   int         _num_pools;
  54 
  55 protected:
  56   volatile instanceOop _memory_mgr_obj;
  57 
  58 public:
  59   MemoryManager();
  60 
  61   int num_memory_pools() const           { return _num_pools; }
  62   MemoryPool* get_memory_pool(int index) {
  63     assert(index >= 0 && index < _num_pools, "Invalid index");
  64     return _pools[index];
  65   }
  66 
  67   void add_pool(MemoryPool* pool);
  68 
  69   bool is_manager(instanceHandle mh)     { return mh() == _memory_mgr_obj; }
  70 
  71   virtual instanceOop get_memory_manager_instance(TRAPS);
  72   virtual bool is_gc_memory_manager()    { return false; }
  73   virtual const char* name() = 0;
  74 
  75   // GC support
  76   void oops_do(OopClosure* f);
  77 
  78   // Static factory methods to get a memory manager of a specific type
  79   static MemoryManager*   get_code_cache_memory_manager();
  80   static MemoryManager*   get_metaspace_memory_manager();
  81 };
  82 
  83 class CodeCacheMemoryManager : public MemoryManager {
  84 private:
  85 public:
  86   CodeCacheMemoryManager() : MemoryManager() {}
  87 
  88   const char* name() { return "CodeCacheManager"; }
  89 };
  90 
  91 class MetaspaceMemoryManager : public MemoryManager {
  92 public:
  93   MetaspaceMemoryManager() : MemoryManager() {}
  94 
  95   const char* name() { return "Metaspace Manager"; }
  96 };
  97 
  98 class GCStatInfo : public ResourceObj {
  99 private:
 100   size_t _index;
 101   jlong  _start_time;
 102   jlong  _end_time;
 103 
 104   // We keep memory usage of all memory pools
 105   MemoryUsage* _before_gc_usage_array;
 106   MemoryUsage* _after_gc_usage_array;
 107   int          _usage_array_size;
 108 
 109   void set_gc_usage(int pool_index, MemoryUsage, bool before_gc);
 110 
 111 public:
 112   GCStatInfo(int num_pools);
 113   ~GCStatInfo();
 114 
 115   size_t gc_index()               { return _index; }
 116   jlong  start_time()             { return _start_time; }
 117   jlong  end_time()               { return _end_time; }
 118   int    usage_array_size()       { return _usage_array_size; }
 119   MemoryUsage before_gc_usage_for_pool(int pool_index) {
 120     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 121     return _before_gc_usage_array[pool_index];
 122   }
 123   MemoryUsage after_gc_usage_for_pool(int pool_index) {
 124     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 125     return _after_gc_usage_array[pool_index];
 126   }
 127 
 128   MemoryUsage* before_gc_usage_array() { return _before_gc_usage_array; }
 129   MemoryUsage* after_gc_usage_array()  { return _after_gc_usage_array; }
 130 
 131   void set_index(size_t index)    { _index = index; }
 132   void set_start_time(jlong time) { _start_time = time; }
 133   void set_end_time(jlong time)   { _end_time = time; }
 134   void set_before_gc_usage(int pool_index, MemoryUsage usage) {
 135     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 136     set_gc_usage(pool_index, usage, true /* before gc */);
 137   }
 138   void set_after_gc_usage(int pool_index, MemoryUsage usage) {
 139     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 140     set_gc_usage(pool_index, usage, false /* after gc */);
 141   }
 142 
 143   void clear();
 144 };
 145 
 146 class GCMemoryManager : public MemoryManager {
 147 private:
 148   // TODO: We should unify the GCCounter and GCMemoryManager statistic
 149   size_t       _num_collections;
 150   elapsedTimer _accumulated_timer;
 151   elapsedTimer _gc_timer;         // for measuring every GC duration
 152   GCStatInfo*  _last_gc_stat;
 153   Mutex*       _last_gc_lock;
 154   GCStatInfo*  _current_gc_stat;
 155   int          _num_gc_threads;
 156   volatile bool _notification_enabled;
 157 public:
 158   GCMemoryManager();
 159   ~GCMemoryManager();
 160 
 161   void   initialize_gc_stat_info();
 162 
 163   bool   is_gc_memory_manager()         { return true; }
 164   jlong  gc_time_ms()                   { return _accumulated_timer.milliseconds(); }
 165   size_t gc_count()                     { return _num_collections; }
 166   int    num_gc_threads()               { return _num_gc_threads; }
 167   void   set_num_gc_threads(int count)  { _num_gc_threads = count; }
 168 
 169   void   gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 170                   bool recordAccumulatedGCTime);
 171   void   gc_end(bool recordPostGCUsage, bool recordAccumulatedGCTime,
 172                 bool recordGCEndTime, bool countCollection, GCCause::Cause cause);
 173 
 174   void        reset_gc_stat()   { _num_collections = 0; _accumulated_timer.reset(); }
 175 
 176   // Copy out _last_gc_stat to the given destination, returning
 177   // the collection count. Zero signifies no gc has taken place.
 178   size_t get_last_gc_stat(GCStatInfo* dest);
 179 
 180   void set_notification_enabled(bool enabled) { _notification_enabled = enabled; }
 181   bool is_notification_enabled() { return _notification_enabled; }
 182 };
 183 
 184 #endif // SHARE_VM_SERVICES_MEMORYMANAGER_HPP