1 /*
   2  * Copyright (c) 2003, 2017, 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 "memory/allocation.hpp"
  29 #include "runtime/timer.hpp"
  30 #include "services/memoryUsage.hpp"
  31 
  32 // A memory manager is responsible for managing one or more memory pools.
  33 // The garbage collector is one type of memory managers responsible
  34 // for reclaiming memory occupied by unreachable objects.  A Java virtual
  35 // machine may have one or more memory managers.   It may
  36 // add or remove memory managers during execution.
  37 // A memory pool can be managed by more than one memory managers.
  38 
  39 class MemoryPool;
  40 class GCMemoryManager;
  41 class OopClosure;
  42 
  43 class MemoryManager : public CHeapObj<mtInternal> {
  44 private:
  45   enum {
  46     max_num_pools = 10
  47   };
  48 
  49   MemoryPool* _pools[max_num_pools];
  50   int         _num_pools;
  51 
  52 protected:
  53   volatile instanceOop _memory_mgr_obj;
  54 
  55 public:
  56   MemoryManager();
  57 
  58   int num_memory_pools() const           { return _num_pools; }
  59   MemoryPool* get_memory_pool(int index) {
  60     assert(index >= 0 && index < _num_pools, "Invalid index");
  61     return _pools[index];
  62   }
  63 
  64   void add_pool(MemoryPool* pool);
  65 
  66   bool is_manager(instanceHandle mh)     { return mh() == _memory_mgr_obj; }
  67 
  68   virtual instanceOop get_memory_manager_instance(TRAPS);
  69   virtual bool is_gc_memory_manager()    { return false; }
  70   virtual const char* name() = 0;
  71 
  72   // GC support
  73   void oops_do(OopClosure* f);
  74 
  75   // Static factory methods to get a memory manager of a specific type
  76   static MemoryManager*   get_code_cache_memory_manager();
  77   static MemoryManager*   get_metaspace_memory_manager();
  78 };
  79 
  80 class CodeCacheMemoryManager : public MemoryManager {
  81 private:
  82 public:
  83   CodeCacheMemoryManager() : MemoryManager() {}
  84 
  85   const char* name() { return "CodeCacheManager"; }
  86 };
  87 
  88 class MetaspaceMemoryManager : public MemoryManager {
  89 public:
  90   MetaspaceMemoryManager() : MemoryManager() {}
  91 
  92   const char* name() { return "Metaspace Manager"; }
  93 };
  94 
  95 class GCStatInfo : public ResourceObj {
  96 private:
  97   size_t _index;
  98   jlong  _start_time;
  99   jlong  _end_time;
 100 
 101   // We keep memory usage of all memory pools
 102   MemoryUsage* _before_gc_usage_array;
 103   MemoryUsage* _after_gc_usage_array;
 104   int          _usage_array_size;
 105 
 106   void set_gc_usage(int pool_index, MemoryUsage, bool before_gc);
 107 
 108 public:
 109   GCStatInfo(int num_pools);
 110   ~GCStatInfo();
 111 
 112   size_t gc_index()               { return _index; }
 113   jlong  start_time()             { return _start_time; }
 114   jlong  end_time()               { return _end_time; }
 115   int    usage_array_size()       { return _usage_array_size; }
 116   MemoryUsage before_gc_usage_for_pool(int pool_index) {
 117     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 118     return _before_gc_usage_array[pool_index];
 119   }
 120   MemoryUsage after_gc_usage_for_pool(int pool_index) {
 121     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 122     return _after_gc_usage_array[pool_index];
 123   }
 124 
 125   MemoryUsage* before_gc_usage_array() { return _before_gc_usage_array; }
 126   MemoryUsage* after_gc_usage_array()  { return _after_gc_usage_array; }
 127 
 128   void set_index(size_t index)    { _index = index; }
 129   void set_start_time(jlong time) { _start_time = time; }
 130   void set_end_time(jlong time)   { _end_time = time; }
 131   void set_before_gc_usage(int pool_index, MemoryUsage usage) {
 132     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 133     set_gc_usage(pool_index, usage, true /* before gc */);
 134   }
 135   void set_after_gc_usage(int pool_index, MemoryUsage usage) {
 136     assert(pool_index >= 0 && pool_index < _usage_array_size, "Range checking");
 137     set_gc_usage(pool_index, usage, false /* after gc */);
 138   }
 139 
 140   void clear();
 141 };
 142 
 143 class GCMemoryManager : public MemoryManager {
 144 private:
 145   // TODO: We should unify the GCCounter and GCMemoryManager statistic
 146   size_t       _num_collections;
 147   elapsedTimer _accumulated_timer;
 148   elapsedTimer _gc_timer;         // for measuring every GC duration
 149   GCStatInfo*  _last_gc_stat;
 150   Mutex*       _last_gc_lock;
 151   GCStatInfo*  _current_gc_stat;
 152   int          _num_gc_threads;
 153   volatile bool _notification_enabled;
 154 public:
 155   GCMemoryManager();
 156   ~GCMemoryManager();
 157 
 158   void   initialize_gc_stat_info();
 159 
 160   virtual const char* gc_end_message() = 0;
 161 
 162   bool   is_gc_memory_manager()         { return true; }
 163   jlong  gc_time_ms()                   { return _accumulated_timer.milliseconds(); }
 164   size_t gc_count()                     { return _num_collections; }
 165   int    num_gc_threads()               { return _num_gc_threads; }
 166   void   set_num_gc_threads(int count)  { _num_gc_threads = count; }
 167 
 168   void   gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 169                   bool recordAccumulatedGCTime);
 170   void   gc_end(bool recordPostGCUsage, bool recordAccumulatedGCTime,
 171                 bool recordGCEndTime, bool countCollection, GCCause::Cause cause);
 172 
 173   void        reset_gc_stat()   { _num_collections = 0; _accumulated_timer.reset(); }
 174 
 175   // Copy out _last_gc_stat to the given destination, returning
 176   // the collection count. Zero signifies no gc has taken place.
 177   size_t get_last_gc_stat(GCStatInfo* dest);
 178 
 179   void set_notification_enabled(bool enabled) { _notification_enabled = enabled; }
 180   bool is_notification_enabled() { return _notification_enabled; }
 181 };
 182 
 183 #endif // SHARE_VM_SERVICES_MEMORYMANAGER_HPP