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_GC_G1_G1MEMORYPOOL_HPP 26 #define SHARE_VM_GC_G1_G1MEMORYPOOL_HPP 27 28 #include "gc/g1/g1MonitoringSupport.hpp" 29 #include "services/memoryPool.hpp" 30 #include "services/memoryUsage.hpp" 31 32 // This file contains the three classes that represent the memory 33 // pools of the G1 spaces: G1EdenPool, G1SurvivorPool, and 34 // G1OldGenPool. In G1, unlike our other GCs, we do not have a 35 // physical space for each of those spaces. Instead, we allocate 36 // regions for all three spaces out of a single pool of regions (that 37 // pool basically covers the entire heap). As a result, the eden, 38 // survivor, and old gen are considered logical spaces in G1, as each 39 // is a set of non-contiguous regions. This is also reflected in the 40 // way we map them to memory pools here. The easiest way to have done 41 // this would have been to map the entire G1 heap to a single memory 42 // pool. However, it's helpful to show how large the eden and survivor 43 // get, as this does affect the performance and behavior of G1. Which 44 // is why we introduce the three memory pools implemented here. 45 // 46 // See comments in g1MonitoringSupport.hpp for additional details 47 // on this model. 48 // 49 50 class G1CollectedHeap; 51 52 // This class is shared by the three G1 memory pool classes 53 // (G1EdenPool, G1SurvivorPool, G1OldGenPool). 54 class G1MemoryPoolSuper : public CollectedMemoryPool { 55 protected: 56 const static size_t _undefined_max = (size_t) -1; 57 G1MonitoringSupport* _g1mm; 58 59 // Would only be called from subclasses. 60 G1MemoryPoolSuper(G1CollectedHeap* g1h, 61 const char* name, 62 size_t init_size, 63 size_t max_size, 64 bool support_usage_threshold); 65 }; 66 67 // Memory pool that represents the G1 eden. 68 class G1EdenPool : public G1MemoryPoolSuper { 69 public: 70 G1EdenPool(G1CollectedHeap* g1h); 71 72 size_t used_in_bytes() { 73 return _g1mm->eden_space_used(); 74 } 75 size_t max_size() const { 76 return _undefined_max; 77 } 78 MemoryUsage get_memory_usage(); 79 }; 80 81 // Memory pool that represents the G1 survivor. 82 class G1SurvivorPool : public G1MemoryPoolSuper { 83 public: 84 G1SurvivorPool(G1CollectedHeap* g1h); 85 86 size_t used_in_bytes() { 87 return _g1mm->survivor_space_used(); 88 } 89 size_t max_size() const { 90 return _undefined_max; 91 } 92 MemoryUsage get_memory_usage(); 93 }; 94 95 // Memory pool that represents the G1 old gen. 96 class G1OldGenPool : public G1MemoryPoolSuper { 97 public: 98 G1OldGenPool(G1CollectedHeap* g1h); 99 100 size_t used_in_bytes() { 101 return _g1mm->old_space_used(); 102 } 103 size_t max_size() const { 104 return _g1mm->old_gen_max(); 105 } 106 MemoryUsage get_memory_usage(); 107 }; 108 109 #endif // SHARE_VM_GC_G1_G1MEMORYPOOL_HPP