1 /* 2 * Copyright (c) 2003, 2012, 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 "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 "services/gcNotifier.hpp" 37 #include "utilities/dtrace.hpp" 38 39 #ifndef USDT2 40 HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__begin, char*, int, char*, int, 41 size_t, size_t, size_t, size_t); 42 HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__end, char*, int, char*, int, 43 size_t, size_t, size_t, size_t); 44 #endif /* !USDT2 */ 45 46 MemoryManager::MemoryManager() { 47 _num_pools = 0; 48 _memory_mgr_obj = NULL; 49 } 50 51 void MemoryManager::add_pool(MemoryPool* pool) { 52 assert(_num_pools < MemoryManager::max_num_pools, "_num_pools exceeds the max"); 53 if (_num_pools < MemoryManager::max_num_pools) { 54 _pools[_num_pools] = pool; 55 _num_pools++; 56 } 57 pool->add_manager(this); 58 } 59 60 MemoryManager* MemoryManager::get_code_cache_memory_manager() { 61 return (MemoryManager*) new CodeCacheMemoryManager(); 62 } 63 64 GCMemoryManager* MemoryManager::get_copy_memory_manager() { 65 return (GCMemoryManager*) new CopyMemoryManager(); 66 } 67 68 GCMemoryManager* MemoryManager::get_msc_memory_manager() { 69 return (GCMemoryManager*) new MSCMemoryManager(); 70 } 71 72 GCMemoryManager* MemoryManager::get_parnew_memory_manager() { 73 return (GCMemoryManager*) new ParNewMemoryManager(); 74 } 75 76 GCMemoryManager* MemoryManager::get_cms_memory_manager() { 77 return (GCMemoryManager*) new CMSMemoryManager(); 78 } 79 80 GCMemoryManager* MemoryManager::get_psScavenge_memory_manager() { 81 return (GCMemoryManager*) new PSScavengeMemoryManager(); 82 } 83 84 GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() { 85 return (GCMemoryManager*) new PSMarkSweepMemoryManager(); 86 } 87 88 GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() { 89 return (GCMemoryManager*) new G1YoungGenMemoryManager(); 90 } 91 92 GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() { 93 return (GCMemoryManager*) new G1OldGenMemoryManager(); 94 } 95 96 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) { 97 // Must do an acquire so as to force ordering of subsequent 98 // loads from anything _memory_mgr_obj points to or implies. 99 instanceOop mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj); 100 if (mgr_obj == NULL) { 101 // It's ok for more than one thread to execute the code up to the locked region. 102 // Extra manager instances will just be gc'ed. 103 Klass* k = Management::sun_management_ManagementFactory_klass(CHECK_0); 104 instanceKlassHandle ik(THREAD, k); 105 106 Handle mgr_name = java_lang_String::create_from_str(name(), CHECK_0); 107 108 JavaValue result(T_OBJECT); 109 JavaCallArguments args; 110 args.push_oop(mgr_name); // Argument 1 111 112 Symbol* method_name = NULL; 113 Symbol* signature = NULL; 114 if (is_gc_memory_manager()) { 115 method_name = vmSymbols::createGarbageCollector_name(); 116 signature = vmSymbols::createGarbageCollector_signature(); 117 args.push_oop(Handle()); // Argument 2 (for future extension) 118 } else { 119 method_name = vmSymbols::createMemoryManager_name(); 120 signature = vmSymbols::createMemoryManager_signature(); 121 } 122 123 JavaCalls::call_static(&result, 124 ik, 125 method_name, 126 signature, 127 &args, 128 CHECK_0); 129 130 instanceOop m = (instanceOop) result.get_jobject(); 131 instanceHandle mgr(THREAD, m); 132 133 { 134 // Get lock before setting _memory_mgr_obj 135 // since another thread may have created the instance 136 MutexLocker ml(Management_lock); 137 138 // Check if another thread has created the management object. We reload 139 // _memory_mgr_obj here because some other thread may have initialized 140 // it while we were executing the code before the lock. 141 // 142 // The lock has done an acquire, so the load can't float above it, but 143 // we need to do a load_acquire as above. 144 mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj); 145 if (mgr_obj != NULL) { 146 return mgr_obj; 147 } 148 149 // Get the address of the object we created via call_special. 150 mgr_obj = mgr(); 151 152 // Use store barrier to make sure the memory accesses associated 153 // with creating the management object are visible before publishing 154 // its address. The unlock will publish the store to _memory_mgr_obj 155 // because it does a release first. 156 OrderAccess::release_store_ptr(&_memory_mgr_obj, mgr_obj); 157 } 158 } 159 160 return mgr_obj; 161 } 162 163 void MemoryManager::oops_do(OopClosure* f) { 164 f->do_oop((oop*) &_memory_mgr_obj); 165 } 166 167 GCStatInfo::GCStatInfo(int num_pools) { 168 // initialize the arrays for memory usage 169 _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal); 170 _after_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal); 171 _usage_array_size = num_pools; 172 clear(); 173 } 174 175 GCStatInfo::~GCStatInfo() { 176 FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array, mtInternal); 177 FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array, mtInternal); 178 } 179 180 void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) { 181 MemoryUsage* gc_usage_array; 182 if (before_gc) { 183 gc_usage_array = _before_gc_usage_array; 184 } else { 185 gc_usage_array = _after_gc_usage_array; 186 } 187 gc_usage_array[pool_index] = usage; 188 } 189 190 void GCStatInfo::clear() { 191 _index = 0; 192 _start_time = 0L; 193 _end_time = 0L; 194 size_t len = _usage_array_size * sizeof(MemoryUsage); 195 memset(_before_gc_usage_array, 0, len); 196 memset(_after_gc_usage_array, 0, len); 197 } 198 199 200 GCMemoryManager::GCMemoryManager() : MemoryManager() { 201 _num_collections = 0; 202 _last_gc_stat = NULL; 203 _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true); 204 _current_gc_stat = NULL; 205 _num_gc_threads = 1; 206 _notification_enabled = false; 207 } 208 209 GCMemoryManager::~GCMemoryManager() { 210 delete _last_gc_stat; 211 delete _last_gc_lock; 212 delete _current_gc_stat; 213 } 214 215 void GCMemoryManager::initialize_gc_stat_info() { 216 assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools"); 217 _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools()); 218 _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools()); 219 // tracking concurrent collections we need two objects: one to update, and one to 220 // hold the publicly available "last (completed) gc" information. 221 } 222 223 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage, 224 bool recordAccumulatedGCTime) { 225 assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking"); 226 if (recordAccumulatedGCTime) { 227 _accumulated_timer.start(); 228 } 229 // _num_collections now increases in gc_end, to count completed collections 230 if (recordGCBeginTime) { 231 _current_gc_stat->set_index(_num_collections+1); 232 _current_gc_stat->set_start_time(Management::timestamp()); 233 } 234 235 if (recordPreGCUsage) { 236 // Keep memory usage of all memory pools 237 for (int i = 0; i < MemoryService::num_memory_pools(); i++) { 238 MemoryPool* pool = MemoryService::get_memory_pool(i); 239 MemoryUsage usage = pool->get_memory_usage(); 240 _current_gc_stat->set_before_gc_usage(i, usage); 241 #ifndef USDT2 242 HS_DTRACE_PROBE8(hotspot, mem__pool__gc__begin, 243 name(), strlen(name()), 244 pool->name(), strlen(pool->name()), 245 usage.init_size(), usage.used(), 246 usage.committed(), usage.max_size()); 247 #else /* USDT2 */ 248 HOTSPOT_MEM_POOL_GC_BEGIN( 249 (char *) name(), strlen(name()), 250 (char *) pool->name(), strlen(pool->name()), 251 usage.init_size(), usage.used(), 252 usage.committed(), usage.max_size()); 253 #endif /* USDT2 */ 254 } 255 } 256 } 257 258 // A collector MUST, even if it does not complete for some reason, 259 // make a TraceMemoryManagerStats object where countCollection is true, 260 // to ensure the current gc stat is placed in _last_gc_stat. 261 void GCMemoryManager::gc_end(bool recordPostGCUsage, 262 bool recordAccumulatedGCTime, 263 bool recordGCEndTime, bool countCollection, 264 GCCause::Cause cause) { 265 if (recordAccumulatedGCTime) { 266 _accumulated_timer.stop(); 267 } 268 if (recordGCEndTime) { 269 _current_gc_stat->set_end_time(Management::timestamp()); 270 } 271 272 if (recordPostGCUsage) { 273 int i; 274 // keep the last gc statistics for all memory pools 275 for (i = 0; i < MemoryService::num_memory_pools(); i++) { 276 MemoryPool* pool = MemoryService::get_memory_pool(i); 277 MemoryUsage usage = pool->get_memory_usage(); 278 279 #ifndef USDT2 280 HS_DTRACE_PROBE8(hotspot, mem__pool__gc__end, 281 name(), strlen(name()), 282 pool->name(), strlen(pool->name()), 283 usage.init_size(), usage.used(), 284 usage.committed(), usage.max_size()); 285 #else /* USDT2 */ 286 HOTSPOT_MEM_POOL_GC_END( 287 (char *) name(), strlen(name()), 288 (char *) pool->name(), strlen(pool->name()), 289 usage.init_size(), usage.used(), 290 usage.committed(), usage.max_size()); 291 #endif /* USDT2 */ 292 293 _current_gc_stat->set_after_gc_usage(i, usage); 294 } 295 296 // Set last collection usage of the memory pools managed by this collector 297 for (i = 0; i < num_memory_pools(); i++) { 298 MemoryPool* pool = get_memory_pool(i); 299 MemoryUsage usage = pool->get_memory_usage(); 300 301 // Compare with GC usage threshold 302 pool->set_last_collection_usage(usage); 303 LowMemoryDetector::detect_after_gc_memory(pool); 304 } 305 } 306 307 if (countCollection) { 308 _num_collections++; 309 // alternately update two objects making one public when complete 310 { 311 MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag); 312 GCStatInfo *tmp = _last_gc_stat; 313 _last_gc_stat = _current_gc_stat; 314 _current_gc_stat = tmp; 315 // reset the current stat for diagnosability purposes 316 _current_gc_stat->clear(); 317 } 318 319 if (is_notification_enabled()) { 320 bool isMajorGC = this == MemoryService::get_major_gc_manager(); 321 GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC", 322 GCCause::to_string(cause)); 323 } 324 } 325 } 326 327 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) { 328 MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag); 329 if (_last_gc_stat->gc_index() != 0) { 330 dest->set_index(_last_gc_stat->gc_index()); 331 dest->set_start_time(_last_gc_stat->start_time()); 332 dest->set_end_time(_last_gc_stat->end_time()); 333 assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(), 334 "Must have same array size"); 335 size_t len = dest->usage_array_size() * sizeof(MemoryUsage); 336 memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len); 337 memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len); 338 } 339 return _last_gc_stat->gc_index(); 340 }