memoryManager.cpp revision 1879:f95d63e2154a 
1/*
2 * Copyright (c) 2003, 2010, 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.
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23 */
24
25#include "precompiled.hpp"
26#include "classfile/systemDictionary.hpp"
27#include "classfile/vmSymbols.hpp"
28#include "oops/oop.inline.hpp"
29#include "runtime/handles.inline.hpp"
30#include "runtime/javaCalls.hpp"
31#include "services/lowMemoryDetector.hpp"
32#include "services/management.hpp"
33#include "services/memoryManager.hpp"
34#include "services/memoryPool.hpp"
35#include "services/memoryService.hpp"
36#include "utilities/dtrace.hpp"
37
38HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__begin, char*, int, char*, int,
39  size_t, size_t, size_t, size_t);
40HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__end, char*, int, char*, int,
41  size_t, size_t, size_t, size_t);
42
43MemoryManager::MemoryManager() {
44  _num_pools = 0;
45  _memory_mgr_obj = NULL;
46}
47
48void MemoryManager::add_pool(MemoryPool* pool) {
49  assert(_num_pools < MemoryManager::max_num_pools, "_num_pools exceeds the max");
50  if (_num_pools < MemoryManager::max_num_pools) {
51    _pools[_num_pools] = pool;
52    _num_pools++;
53  }
54  pool->add_manager(this);
55}
56
57MemoryManager* MemoryManager::get_code_cache_memory_manager() {
58  return (MemoryManager*) new CodeCacheMemoryManager();
59}
60
61GCMemoryManager* MemoryManager::get_copy_memory_manager() {
62  return (GCMemoryManager*) new CopyMemoryManager();
63}
64
65GCMemoryManager* MemoryManager::get_msc_memory_manager() {
66  return (GCMemoryManager*) new MSCMemoryManager();
67}
68
69GCMemoryManager* MemoryManager::get_parnew_memory_manager() {
70  return (GCMemoryManager*) new ParNewMemoryManager();
71}
72
73GCMemoryManager* MemoryManager::get_cms_memory_manager() {
74  return (GCMemoryManager*) new CMSMemoryManager();
75}
76
77GCMemoryManager* MemoryManager::get_psScavenge_memory_manager() {
78  return (GCMemoryManager*) new PSScavengeMemoryManager();
79}
80
81GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() {
82  return (GCMemoryManager*) new PSMarkSweepMemoryManager();
83}
84
85GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() {
86  return (GCMemoryManager*) new G1YoungGenMemoryManager();
87}
88
89GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() {
90  return (GCMemoryManager*) new G1OldGenMemoryManager();
91}
92
93instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
94  // Must do an acquire so as to force ordering of subsequent
95  // loads from anything _memory_mgr_obj points to or implies.
96  instanceOop mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
97  if (mgr_obj == NULL) {
98    // It's ok for more than one thread to execute the code up to the locked region.
99    // Extra manager instances will just be gc'ed.
100    klassOop k = Management::sun_management_ManagementFactory_klass(CHECK_0);
101    instanceKlassHandle ik(THREAD, k);
102
103    Handle mgr_name = java_lang_String::create_from_str(name(), CHECK_0);
104
105    JavaValue result(T_OBJECT);
106    JavaCallArguments args;
107    args.push_oop(mgr_name);    // Argument 1
108
109    symbolHandle method_name;
110    symbolHandle signature;
111    if (is_gc_memory_manager()) {
112      method_name = vmSymbolHandles::createGarbageCollector_name();
113      signature = vmSymbolHandles::createGarbageCollector_signature();
114      args.push_oop(Handle());      // Argument 2 (for future extension)
115    } else {
116      method_name = vmSymbolHandles::createMemoryManager_name();
117      signature = vmSymbolHandles::createMemoryManager_signature();
118    }
119
120    JavaCalls::call_static(&result,
121                           ik,
122                           method_name,
123                           signature,
124                           &args,
125                           CHECK_0);
126
127    instanceOop m = (instanceOop) result.get_jobject();
128    instanceHandle mgr(THREAD, m);
129
130    {
131      // Get lock before setting _memory_mgr_obj
132      // since another thread may have created the instance
133      MutexLocker ml(Management_lock);
134
135      // Check if another thread has created the management object.  We reload
136      // _memory_mgr_obj here because some other thread may have initialized
137      // it while we were executing the code before the lock.
138      //
139      // The lock has done an acquire, so the load can't float above it, but
140      // we need to do a load_acquire as above.
141      mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
142      if (mgr_obj != NULL) {
143         return mgr_obj;
144      }
145
146      // Get the address of the object we created via call_special.
147      mgr_obj = mgr();
148
149      // Use store barrier to make sure the memory accesses associated
150      // with creating the management object are visible before publishing
151      // its address.  The unlock will publish the store to _memory_mgr_obj
152      // because it does a release first.
153      OrderAccess::release_store_ptr(&_memory_mgr_obj, mgr_obj);
154    }
155  }
156
157  return mgr_obj;
158}
159
160void MemoryManager::oops_do(OopClosure* f) {
161  f->do_oop((oop*) &_memory_mgr_obj);
162}
163
164GCStatInfo::GCStatInfo(int num_pools) {
165  // initialize the arrays for memory usage
166  _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools);
167  _after_gc_usage_array  = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools);
168  size_t len = num_pools * sizeof(MemoryUsage);
169  memset(_before_gc_usage_array, 0, len);
170  memset(_after_gc_usage_array, 0, len);
171  _usage_array_size = num_pools;
172}
173
174GCStatInfo::~GCStatInfo() {
175  FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array);
176  FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array);
177}
178
179void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) {
180  MemoryUsage* gc_usage_array;
181  if (before_gc) {
182    gc_usage_array = _before_gc_usage_array;
183  } else {
184    gc_usage_array = _after_gc_usage_array;
185  }
186  gc_usage_array[pool_index] = usage;
187}
188
189void GCStatInfo::clear() {
190  _index = 0;
191  _start_time = 0L;
192  _end_time = 0L;
193  size_t len = _usage_array_size * sizeof(MemoryUsage);
194  memset(_before_gc_usage_array, 0, len);
195  memset(_after_gc_usage_array, 0, len);
196}
197
198
199GCMemoryManager::GCMemoryManager() : MemoryManager() {
200  _num_collections = 0;
201  _last_gc_stat = NULL;
202  _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true);
203  _current_gc_stat = NULL;
204  _num_gc_threads = 1;
205}
206
207GCMemoryManager::~GCMemoryManager() {
208  delete _last_gc_stat;
209  delete _last_gc_lock;
210  delete _current_gc_stat;
211}
212
213void GCMemoryManager::initialize_gc_stat_info() {
214  assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
215  _last_gc_stat = new GCStatInfo(MemoryService::num_memory_pools());
216  _current_gc_stat = new GCStatInfo(MemoryService::num_memory_pools());
217  // tracking concurrent collections we need two objects: one to update, and one to
218  // hold the publicly available "last (completed) gc" information.
219}
220
221void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
222                               bool recordAccumulatedGCTime) {
223  assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking");
224  if (recordAccumulatedGCTime) {
225    _accumulated_timer.start();
226  }
227  // _num_collections now increases in gc_end, to count completed collections
228  if (recordGCBeginTime) {
229    _current_gc_stat->set_index(_num_collections+1);
230    _current_gc_stat->set_start_time(Management::timestamp());
231  }
232
233  if (recordPreGCUsage) {
234    // Keep memory usage of all memory pools
235    for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
236      MemoryPool* pool = MemoryService::get_memory_pool(i);
237      MemoryUsage usage = pool->get_memory_usage();
238      _current_gc_stat->set_before_gc_usage(i, usage);
239      HS_DTRACE_PROBE8(hotspot, mem__pool__gc__begin,
240        name(), strlen(name()),
241        pool->name(), strlen(pool->name()),
242        usage.init_size(), usage.used(),
243        usage.committed(), usage.max_size());
244    }
245  }
246}
247
248// A collector MUST, even if it does not complete for some reason,
249// make a TraceMemoryManagerStats object where countCollection is true,
250// to ensure the current gc stat is placed in _last_gc_stat.
251void GCMemoryManager::gc_end(bool recordPostGCUsage,
252                             bool recordAccumulatedGCTime,
253                             bool recordGCEndTime, bool countCollection) {
254  if (recordAccumulatedGCTime) {
255    _accumulated_timer.stop();
256  }
257  if (recordGCEndTime) {
258    _current_gc_stat->set_end_time(Management::timestamp());
259  }
260
261  if (recordPostGCUsage) {
262    int i;
263    // keep the last gc statistics for all memory pools
264    for (i = 0; i < MemoryService::num_memory_pools(); i++) {
265      MemoryPool* pool = MemoryService::get_memory_pool(i);
266      MemoryUsage usage = pool->get_memory_usage();
267
268      HS_DTRACE_PROBE8(hotspot, mem__pool__gc__end,
269        name(), strlen(name()),
270        pool->name(), strlen(pool->name()),
271        usage.init_size(), usage.used(),
272        usage.committed(), usage.max_size());
273
274      _current_gc_stat->set_after_gc_usage(i, usage);
275    }
276
277    // Set last collection usage of the memory pools managed by this collector
278    for (i = 0; i < num_memory_pools(); i++) {
279      MemoryPool* pool = get_memory_pool(i);
280      MemoryUsage usage = pool->get_memory_usage();
281
282      // Compare with GC usage threshold
283      pool->set_last_collection_usage(usage);
284      LowMemoryDetector::detect_after_gc_memory(pool);
285    }
286  }
287  if (countCollection) {
288    _num_collections++;
289    // alternately update two objects making one public when complete
290    {
291      MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
292      GCStatInfo *tmp = _last_gc_stat;
293      _last_gc_stat = _current_gc_stat;
294      _current_gc_stat = tmp;
295      // reset the current stat for diagnosability purposes
296      _current_gc_stat->clear();
297    }
298  }
299}
300
301size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
302  MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
303  if (_last_gc_stat->gc_index() != 0) {
304    dest->set_index(_last_gc_stat->gc_index());
305    dest->set_start_time(_last_gc_stat->start_time());
306    dest->set_end_time(_last_gc_stat->end_time());
307    assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
308           "Must have same array size");
309    size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
310    memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
311    memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
312  }
313  return _last_gc_stat->gc_index();
314}
315