1 /*
   2  * Copyright (c) 2011, 2019, 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 #include "precompiled.hpp"
  26 #include "gc/g1/g1CollectedHeap.inline.hpp"
  27 #include "gc/g1/g1MonitoringSupport.hpp"
  28 #include "gc/g1/g1Policy.hpp"
  29 #include "gc/g1/g1MemoryPool.hpp"
  30 #include "gc/shared/hSpaceCounters.hpp"
  31 #include "memory/metaspaceCounters.hpp"
  32 #include "services/memoryPool.hpp"
  33 
  34 class G1GenerationCounters : public GenerationCounters {
  35 protected:
  36   G1MonitoringSupport* _g1mm;
  37 
  38 public:
  39   G1GenerationCounters(G1MonitoringSupport* g1mm,
  40                        const char* name, int ordinal, int spaces,
  41                        size_t min_capacity, size_t max_capacity,
  42                        size_t curr_capacity)
  43   : GenerationCounters(name, ordinal, spaces, min_capacity,
  44                        max_capacity, curr_capacity), _g1mm(g1mm) { }
  45 };
  46 
  47 class G1YoungGenerationCounters : public G1GenerationCounters {
  48 public:
  49   // We pad the capacity three times given that the young generation
  50   // contains three spaces (eden and two survivors).
  51   G1YoungGenerationCounters(G1MonitoringSupport* g1mm, const char* name, size_t max_size)
  52   : G1GenerationCounters(g1mm, name, 0 /* ordinal */, 3 /* spaces */,
  53                          G1MonitoringSupport::pad_capacity(0, 3) /* min_capacity */,
  54                          G1MonitoringSupport::pad_capacity(max_size, 3),
  55                          G1MonitoringSupport::pad_capacity(0, 3) /* curr_capacity */) {
  56     if (UsePerfData) {
  57       update_all();
  58     }
  59   }
  60 
  61   virtual void update_all() {
  62     size_t committed =
  63               G1MonitoringSupport::pad_capacity(_g1mm->young_gen_committed(), 3);
  64     _current_size->set_value(committed);
  65   }
  66 };
  67 
  68 class G1OldGenerationCounters : public G1GenerationCounters {
  69 public:
  70   G1OldGenerationCounters(G1MonitoringSupport* g1mm, const char* name, size_t max_size)
  71   : G1GenerationCounters(g1mm, name, 1 /* ordinal */, 1 /* spaces */,
  72                          G1MonitoringSupport::pad_capacity(0) /* min_capacity */,
  73                          G1MonitoringSupport::pad_capacity(max_size),
  74                          G1MonitoringSupport::pad_capacity(0) /* curr_capacity */) {
  75     if (UsePerfData) {
  76       update_all();
  77     }
  78   }
  79 
  80   virtual void update_all() {
  81     size_t committed =
  82               G1MonitoringSupport::pad_capacity(_g1mm->old_gen_committed());
  83     _current_size->set_value(committed);
  84   }
  85 };
  86 
  87 G1MonitoringSupport::G1MonitoringSupport(G1CollectedHeap* g1h) :
  88   _g1h(g1h),
  89   _incremental_memory_manager("G1 Young Generation", "end of minor GC"),
  90   _full_gc_memory_manager("G1 Old Generation", "end of major GC"),
  91   _eden_space_pool(NULL),
  92   _survivor_space_pool(NULL),
  93   _old_gen_pool(NULL),
  94   _incremental_collection_counters(NULL),
  95   _full_collection_counters(NULL),
  96   _conc_collection_counters(NULL),
  97   _young_gen_counters(NULL),
  98   _old_gen_counters(NULL),
  99   _old_space_counters(NULL),
 100   _eden_space_counters(NULL),
 101   _from_space_counters(NULL),
 102   _to_space_counters(NULL),
 103 
 104   _overall_committed(0),
 105   _overall_used(0),
 106   _young_gen_committed(0),
 107   _old_gen_committed(0),
 108 
 109   _eden_space_committed(0),
 110   _eden_space_used(0),
 111   _survivor_space_committed(0),
 112   _survivor_space_used(0),
 113   _old_gen_used(0) {
 114 
 115   recalculate_sizes();
 116 
 117   // Counters for garbage collections
 118   //
 119   //  name "collector.0".  In a generational collector this would be the
 120   // young generation collection.
 121   _incremental_collection_counters =
 122     new CollectorCounters("G1 young collection pauses", 0);
 123   //   name "collector.1".  In a generational collector this would be the
 124   // old generation collection.
 125   _full_collection_counters =
 126     new CollectorCounters("G1 full collection pauses", 1);
 127   //   name "collector.2".  In a generational collector this would be the
 128   // STW phases in concurrent collection.
 129   _conc_collection_counters =
 130     new CollectorCounters("G1 concurrent cycle pauses", 2);
 131 
 132   // "Generation" and "Space" counters.
 133   //
 134   //  name "generation.1" This is logically the old generation in
 135   // generational GC terms.  The "1, 1" parameters are for
 136   // the n-th generation (=1) with 1 space.
 137   // Counters are created from minCapacity, maxCapacity, and capacity
 138   _old_gen_counters = new G1OldGenerationCounters(this, "old", _g1h->max_capacity());
 139 
 140   //  name  "generation.1.space.0"
 141   // Counters are created from maxCapacity, capacity, initCapacity,
 142   // and used.
 143   _old_space_counters = new HSpaceCounters(_old_gen_counters->name_space(),
 144     "space", 0 /* ordinal */,
 145     pad_capacity(g1h->max_capacity()) /* max_capacity */,
 146     pad_capacity(_old_gen_committed) /* init_capacity */);
 147 
 148   //   Young collection set
 149   //  name "generation.0".  This is logically the young generation.
 150   //  The "0, 3" are parameters for the n-th generation (=0) with 3 spaces.
 151   // See  _old_collection_counters for additional counters
 152   _young_gen_counters = new G1YoungGenerationCounters(this, "young", _g1h->max_capacity());
 153 
 154   const char* young_collection_name_space = _young_gen_counters->name_space();
 155 
 156   //  name "generation.0.space.0"
 157   // See _old_space_counters for additional counters
 158   _eden_space_counters = new HSpaceCounters(young_collection_name_space,
 159     "eden", 0 /* ordinal */,
 160     pad_capacity(g1h->max_capacity()) /* max_capacity */,
 161     pad_capacity(_eden_space_committed) /* init_capacity */);
 162 
 163   //  name "generation.0.space.1"
 164   // See _old_space_counters for additional counters
 165   // Set the arguments to indicate that this survivor space is not used.
 166   _from_space_counters = new HSpaceCounters(young_collection_name_space,
 167     "s0", 1 /* ordinal */,
 168     pad_capacity(0) /* max_capacity */,
 169     pad_capacity(0) /* init_capacity */);
 170   // Given that this survivor space is not used, we update it here
 171   // once to reflect that its used space is 0 so that we don't have to
 172   // worry about updating it again later.
 173   if (UsePerfData) {
 174     _from_space_counters->update_used(0);
 175   }
 176 
 177   //  name "generation.0.space.2"
 178   // See _old_space_counters for additional counters
 179   _to_space_counters = new HSpaceCounters(young_collection_name_space,
 180     "s1", 2 /* ordinal */,
 181     pad_capacity(g1h->max_capacity()) /* max_capacity */,
 182     pad_capacity(_survivor_space_committed) /* init_capacity */);
 183 }
 184 
 185 G1MonitoringSupport::~G1MonitoringSupport() {
 186   delete _eden_space_pool;
 187   delete _survivor_space_pool;
 188   delete _old_gen_pool;
 189 }
 190 
 191 void G1MonitoringSupport::initialize_serviceability() {
 192   _eden_space_pool = new G1EdenPool(_g1h, _eden_space_committed);
 193   _survivor_space_pool = new G1SurvivorPool(_g1h, _survivor_space_committed);
 194   _old_gen_pool = new G1OldGenPool(_g1h, _old_gen_committed, _g1h->max_capacity());
 195 
 196   _full_gc_memory_manager.add_pool(_eden_space_pool);
 197   _full_gc_memory_manager.add_pool(_survivor_space_pool);
 198   _full_gc_memory_manager.add_pool(_old_gen_pool);
 199 
 200   _incremental_memory_manager.add_pool(_eden_space_pool);
 201   _incremental_memory_manager.add_pool(_survivor_space_pool);
 202   _incremental_memory_manager.add_pool(_old_gen_pool, false /* always_affected_by_gc */);
 203 }
 204 
 205 MemoryUsage G1MonitoringSupport::memory_usage() {
 206   MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
 207   return MemoryUsage(InitialHeapSize, _overall_used, _overall_committed, _g1h->max_capacity());
 208 }
 209 
 210 GrowableArray<GCMemoryManager*> G1MonitoringSupport::memory_managers() {
 211   GrowableArray<GCMemoryManager*> memory_managers(2);
 212   memory_managers.append(&_incremental_memory_manager);
 213   memory_managers.append(&_full_gc_memory_manager);
 214   return memory_managers;
 215 }
 216 
 217 GrowableArray<MemoryPool*> G1MonitoringSupport::memory_pools() {
 218   GrowableArray<MemoryPool*> memory_pools(3);
 219   memory_pools.append(_eden_space_pool);
 220   memory_pools.append(_survivor_space_pool);
 221   memory_pools.append(_old_gen_pool);
 222   return memory_pools;
 223 }
 224 
 225 void G1MonitoringSupport::recalculate_sizes() {
 226   assert_heap_locked_or_at_safepoint(true);
 227 
 228   MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
 229   // Recalculate all the sizes from scratch.
 230 
 231   // This never includes used bytes of current allocating heap region.
 232   _overall_used = _g1h->used_unlocked();
 233   _eden_space_used = _g1h->eden_regions_used_bytes();
 234   _survivor_space_used = _g1h->survivor_regions_used_bytes();
 235 
 236   // _overall_used and _eden_space_used are obtained concurrently so
 237   // may be inconsistent with each other. To prevent _old_gen_used going negative,
 238   // use smaller value to substract.
 239   _old_gen_used = _overall_used - MIN2(_overall_used, _eden_space_used + _survivor_space_used);
 240 
 241   uint survivor_list_length = _g1h->survivor_regions_count();
 242   // Max length includes any potential extensions to the young gen
 243   // we'll do when the GC locker is active.
 244   uint young_list_max_length = _g1h->policy()->young_list_max_length();
 245   assert(young_list_max_length >= survivor_list_length, "invariant");
 246   uint eden_list_max_length = young_list_max_length - survivor_list_length;
 247 
 248   // First calculate the committed sizes that can be calculated independently.
 249   _survivor_space_committed = survivor_list_length * HeapRegion::GrainBytes;
 250   _old_gen_committed = HeapRegion::align_up_to_region_byte_size(_old_gen_used);
 251 
 252   // Next, start with the overall committed size.
 253   _overall_committed = _g1h->capacity();
 254   size_t committed = _overall_committed;
 255 
 256   // Remove the committed size we have calculated so far (for the
 257   // survivor and old space).
 258   assert(committed >= (_survivor_space_committed + _old_gen_committed), "sanity");
 259   committed -= _survivor_space_committed + _old_gen_committed;
 260 
 261   // Next, calculate and remove the committed size for the eden.
 262   _eden_space_committed = (size_t) eden_list_max_length * HeapRegion::GrainBytes;
 263   // Somewhat defensive: be robust in case there are inaccuracies in
 264   // the calculations
 265   _eden_space_committed = MIN2(_eden_space_committed, committed);
 266   committed -= _eden_space_committed;
 267 
 268   // Finally, give the rest to the old space...
 269   _old_gen_committed += committed;
 270   // ..and calculate the young gen committed.
 271   _young_gen_committed = _eden_space_committed + _survivor_space_committed;
 272 
 273   assert(_overall_committed ==
 274          (_eden_space_committed + _survivor_space_committed + _old_gen_committed),
 275          "the committed sizes should add up");
 276   // Somewhat defensive: cap the eden used size to make sure it
 277   // never exceeds the committed size.
 278   _eden_space_used = MIN2(_eden_space_used, _eden_space_committed);
 279   // _survivor_space_used is calculated during a safepoint and _survivor_space_committed
 280   // is calculated from survivor region count * heap region size.
 281   assert(_survivor_space_used <= _survivor_space_committed, "Survivor used bytes(" SIZE_FORMAT
 282          ") should be less than or equal to survivor committed(" SIZE_FORMAT ")",
 283          _survivor_space_used, _survivor_space_committed);
 284   // _old_gen_committed is calculated in terms of _old_gen_used value.
 285   assert(_old_gen_used <= _old_gen_committed, "Old gen used bytes(" SIZE_FORMAT
 286          ") should be less than or equal to old gen committed(" SIZE_FORMAT ")",
 287          _old_gen_used, _old_gen_committed);
 288 }
 289 
 290 void G1MonitoringSupport::update_sizes() {
 291   recalculate_sizes();
 292   if (UsePerfData) {
 293     _eden_space_counters->update_capacity(pad_capacity(_eden_space_committed));
 294     _eden_space_counters->update_used(_eden_space_used);
 295    // only the "to" survivor space is active, so we don't need to
 296     // update the counters for the "from" survivor space
 297     _to_space_counters->update_capacity(pad_capacity(_survivor_space_committed));
 298     _to_space_counters->update_used(_survivor_space_used);
 299     _old_space_counters->update_capacity(pad_capacity(_old_gen_committed));
 300     _old_space_counters->update_used(_old_gen_used);
 301 
 302     _young_gen_counters->update_all();
 303     _old_gen_counters->update_all();
 304 
 305     MetaspaceCounters::update_performance_counters();
 306     CompressedClassSpaceCounters::update_performance_counters();
 307   }
 308 }
 309 
 310 void G1MonitoringSupport::update_eden_size() {
 311   // Recalculate everything - this should be fast enough and we are sure that we do not
 312   // miss anything.
 313   recalculate_sizes();
 314   if (UsePerfData) {
 315     _eden_space_counters->update_used(_eden_space_used);
 316   }
 317 }
 318 
 319 MemoryUsage G1MonitoringSupport::eden_space_memory_usage(size_t initial_size, size_t max_size) {
 320   MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
 321 
 322   return MemoryUsage(initial_size,
 323                      _eden_space_used,
 324                      _eden_space_committed,
 325                      max_size);
 326 }
 327 
 328 MemoryUsage G1MonitoringSupport::survivor_space_memory_usage(size_t initial_size, size_t max_size) {
 329   MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
 330 
 331   return MemoryUsage(initial_size,
 332                      _survivor_space_used,
 333                      _survivor_space_committed,
 334                      max_size);
 335 }
 336 
 337 MemoryUsage G1MonitoringSupport::old_gen_memory_usage(size_t initial_size, size_t max_size) {
 338   MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
 339 
 340   return MemoryUsage(initial_size,
 341                      _old_gen_used,
 342                      _old_gen_committed,
 343                      max_size);
 344 }
 345 
 346 G1MonitoringScope::G1MonitoringScope(G1MonitoringSupport* g1mm, bool full_gc, bool all_memory_pools_affected) :
 347   _tcs(full_gc ? g1mm->_full_collection_counters : g1mm->_incremental_collection_counters),
 348   _tms(full_gc ? &g1mm->_full_gc_memory_manager : &g1mm->_incremental_memory_manager,
 349        G1CollectedHeap::heap()->gc_cause(), all_memory_pools_affected) {
 350 }