1 /* 2 * Copyright (c) 2001, 2018, 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_SHARED_COLLECTORPOLICY_HPP 26 #define SHARE_VM_GC_SHARED_COLLECTORPOLICY_HPP 27 28 #include "gc/shared/barrierSet.hpp" 29 #include "gc/shared/cardTableRS.hpp" 30 #include "gc/shared/generationSpec.hpp" 31 #include "memory/allocation.hpp" 32 #include "utilities/macros.hpp" 33 34 // This class (or more correctly, subtypes of this class) 35 // are used to define global garbage collector attributes. 36 // This includes initialization of generations and any other 37 // shared resources they may need. 38 // 39 // In general, all flag adjustment and validation should be 40 // done in initialize_flags(), which is called prior to 41 // initialize_size_info(). 42 // 43 // This class is not fully developed yet. As more collector(s) 44 // are added, it is expected that we will come across further 45 // behavior that requires global attention. The correct place 46 // to deal with those issues is this class. 47 48 // Forward declarations. 49 class GenCollectorPolicy; 50 class AdaptiveSizePolicy; 51 #if INCLUDE_ALL_GCS 52 class ConcurrentMarkSweepPolicy; 53 class G1CollectorPolicy; 54 #endif // INCLUDE_ALL_GCS 55 56 class GCPolicyCounters; 57 class MarkSweepPolicy; 58 59 class CollectorPolicy : public CHeapObj<mtGC> { 60 protected: 61 virtual void initialize_alignments() = 0; 62 virtual void initialize_flags(); 63 virtual void initialize_size_info(); 64 65 DEBUG_ONLY(virtual void assert_flags();) 66 DEBUG_ONLY(virtual void assert_size_info();) 67 68 size_t _initial_heap_byte_size; 69 size_t _max_heap_byte_size; 70 size_t _min_heap_byte_size; 71 72 size_t _space_alignment; 73 size_t _heap_alignment; 74 75 CollectorPolicy(); 76 77 public: 78 void initialize_all() { 79 initialize_alignments(); 80 initialize_flags(); 81 initialize_size_info(); 82 } 83 84 // Return maximum heap alignment that may be imposed by the policy. 85 static size_t compute_heap_alignment(); 86 87 size_t space_alignment() { return _space_alignment; } 88 size_t heap_alignment() { return _heap_alignment; } 89 90 size_t initial_heap_byte_size() { return _initial_heap_byte_size; } 91 size_t max_heap_byte_size() { return _max_heap_byte_size; } 92 size_t min_heap_byte_size() { return _min_heap_byte_size; } 93 }; 94 95 class GenCollectorPolicy : public CollectorPolicy { 96 friend class TestGenCollectorPolicy; 97 friend class VMStructs; 98 99 protected: 100 size_t _min_young_size; 101 size_t _initial_young_size; 102 size_t _max_young_size; 103 size_t _min_old_size; 104 size_t _initial_old_size; 105 size_t _max_old_size; 106 107 // _gen_alignment and _space_alignment will have the same value most of the 108 // time. When using large pages they can differ. 109 size_t _gen_alignment; 110 111 GCPolicyCounters* _gc_policy_counters; 112 113 void initialize_flags(); 114 void initialize_size_info(); 115 116 DEBUG_ONLY(void assert_flags();) 117 DEBUG_ONLY(void assert_size_info();) 118 119 // Compute max heap alignment. 120 size_t compute_max_alignment(); 121 122 // Scale the base_size by NewRatio according to 123 // result = base_size / (NewRatio + 1) 124 // and align by min_alignment() 125 size_t scale_by_NewRatio_aligned(size_t base_size); 126 127 // Bound the value by the given maximum minus the min_alignment. 128 size_t bound_minus_alignment(size_t desired_size, size_t maximum_size); 129 130 public: 131 GenCollectorPolicy(); 132 133 // Accessors 134 size_t min_young_size() { return _min_young_size; } 135 size_t initial_young_size() { return _initial_young_size; } 136 size_t max_young_size() { return _max_young_size; } 137 size_t gen_alignment() { return _gen_alignment; } 138 size_t min_old_size() { return _min_old_size; } 139 size_t initial_old_size() { return _initial_old_size; } 140 size_t max_old_size() { return _max_old_size; } 141 142 // Performance Counter support 143 GCPolicyCounters* counters() { return _gc_policy_counters; } 144 145 // Create the jstat counters for the GC policy. 146 virtual void initialize_gc_policy_counters() = 0; 147 148 size_t young_gen_size_lower_bound(); 149 150 size_t old_gen_size_lower_bound(); 151 }; 152 153 class MarkSweepPolicy : public GenCollectorPolicy { 154 protected: 155 void initialize_alignments(); 156 157 public: 158 MarkSweepPolicy() {} 159 160 void initialize_gc_policy_counters(); 161 }; 162 163 #endif // SHARE_VM_GC_SHARED_COLLECTORPOLICY_HPP