1 /* 2 * Copyright (c) 2007, 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_G1MEMORYPOOL_HPP 26 #define SHARE_VM_SERVICES_G1MEMORYPOOL_HPP 27 28 #include "utilities/macros.hpp" 29 #include "gc/g1/g1MonitoringSupport.hpp" 30 #include "services/memoryPool.hpp" 31 #include "services/memoryUsage.hpp" 32 33 // This file contains the three classes that represent the memory 34 // pools of the G1 spaces: G1EdenPool, G1SurvivorPool, and 35 // G1OldGenPool. In G1, unlike our other GCs, we do not have a 36 // physical space for each of those spaces. Instead, we allocate 37 // regions for all three spaces out of a single pool of regions (that 38 // pool basically covers the entire heap). As a result, the eden, 39 // survivor, and old gen are considered logical spaces in G1, as each 40 // is a set of non-contiguous regions. This is also reflected in the 41 // way we map them to memory pools here. The easiest way to have done 42 // this would have been to map the entire G1 heap to a single memory 43 // pool. However, it's helpful to show how large the eden and survivor 44 // get, as this does affect the performance and behavior of G1. Which 45 // is why we introduce the three memory pools implemented here. 46 // 47 // See comments in g1MonitoringSupport.hpp for additional details 48 // on this model. 49 // 50 51 // This class is shared by the three G1 memory pool classes 52 // (G1EdenPool, G1SurvivorPool, G1OldGenPool). 53 class G1MemoryPoolSuper : public CollectedMemoryPool { 54 protected: 55 const static size_t _undefined_max = (size_t) -1; 56 G1MonitoringSupport* _g1mm; 57 58 // Would only be called from subclasses. 59 G1MemoryPoolSuper(G1CollectedHeap* g1h, 60 const char* name, 61 size_t init_size, 62 size_t max_size, 63 bool support_usage_threshold); 64 }; 65 66 // Memory pool that represents the G1 eden. 67 class G1EdenPool : public G1MemoryPoolSuper { 68 public: 69 G1EdenPool(G1CollectedHeap* g1h); 70 71 size_t used_in_bytes() { 72 return _g1mm->eden_space_used(); 73 } 74 size_t max_size() const { 75 return _undefined_max; 76 } 77 MemoryUsage get_memory_usage(); 78 }; 79 80 // Memory pool that represents the G1 survivor. 81 class G1SurvivorPool : public G1MemoryPoolSuper { 82 public: 83 G1SurvivorPool(G1CollectedHeap* g1h); 84 85 size_t used_in_bytes() { 86 return _g1mm->survivor_space_used(); 87 } 88 size_t max_size() const { 89 return _undefined_max; 90 } 91 MemoryUsage get_memory_usage(); 92 }; 93 94 // Memory pool that represents the G1 old gen. 95 class G1OldGenPool : public G1MemoryPoolSuper { 96 public: 97 G1OldGenPool(G1CollectedHeap* g1h); 98 99 size_t used_in_bytes() { 100 return _g1mm->old_space_used(); 101 } 102 size_t max_size() const { 103 return _g1mm->old_gen_max(); 104 } 105 MemoryUsage get_memory_usage(); 106 }; 107 108 #endif // SHARE_VM_SERVICES_G1MEMORYPOOL_HPP