1 /* 2 * Copyright (c) 2018, Red Hat, Inc. and/or its affiliates. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEURISTICS_HPP 25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEURISTICS_HPP 26 27 #include "gc_implementation/shenandoah/shenandoahHeap.hpp" 28 #include "gc_implementation/shenandoah/shenandoahPhaseTimings.hpp" 29 #include "memory/allocation.hpp" 30 #include "runtime/globals_extension.hpp" 31 32 #define SHENANDOAH_ERGO_DISABLE_FLAG(name) \ 33 do { \ 34 if (FLAG_IS_DEFAULT(name) && (name)) { \ 35 log_info(gc)("Heuristics ergonomically sets -XX:-" #name); \ 36 FLAG_SET_DEFAULT(name, false); \ 37 } \ 38 } while (0) 39 40 #define SHENANDOAH_ERGO_ENABLE_FLAG(name) \ 41 do { \ 42 if (FLAG_IS_DEFAULT(name) && !(name)) { \ 43 log_info(gc)("Heuristics ergonomically sets -XX:+" #name); \ 44 FLAG_SET_DEFAULT(name, true); \ 45 } \ 46 } while (0) 47 48 #define SHENANDOAH_ERGO_OVERRIDE_DEFAULT(name, value) \ 49 do { \ 50 if (FLAG_IS_DEFAULT(name)) { \ 51 log_info(gc)("Heuristics ergonomically sets -XX:" #name "=" #value); \ 52 FLAG_SET_DEFAULT(name, value); \ 53 } \ 54 } while (0) 55 56 57 class ShenandoahCollectionSet; 58 class ShenandoahHeapRegion; 59 60 class ShenandoahHeuristics : public CHeapObj<mtGC> { 61 protected: 62 typedef struct { 63 ShenandoahHeapRegion* _region; 64 size_t _garbage; 65 uint64_t _seqnum_last_alloc; 66 } RegionData; 67 68 typedef struct { 69 ShenandoahHeapRegion* _region; 70 size_t _connections; 71 } RegionConnections; 72 73 bool _update_refs_early; 74 bool _update_refs_adaptive; 75 76 RegionData* _region_data; 77 size_t _region_data_size; 78 79 RegionConnections* _region_connects; 80 size_t _region_connects_size; 81 82 uint _degenerated_cycles_in_a_row; 83 uint _successful_cycles_in_a_row; 84 85 size_t _bytes_in_cset; 86 87 double _last_cycle_end; 88 89 static int compare_by_garbage(RegionData a, RegionData b); 90 static int compare_by_alloc_seq_ascending(RegionData a, RegionData b); 91 static int compare_by_alloc_seq_descending(RegionData a, RegionData b); 92 static int compare_by_connects(RegionConnections a, RegionConnections b); 93 94 RegionData* get_region_data_cache(size_t num); 95 96 RegionConnections* get_region_connects_cache(size_t num); 97 98 virtual void choose_collection_set_from_regiondata(ShenandoahCollectionSet* set, 99 RegionData* data, size_t data_size, 100 size_t free) = 0; 101 102 public: 103 104 ShenandoahHeuristics(); 105 virtual ~ShenandoahHeuristics(); 106 107 void record_gc_start(); 108 109 void record_gc_end(); 110 111 virtual void record_cycle_start(); 112 113 virtual void record_cycle_end(); 114 115 virtual void record_phase_time(ShenandoahPhaseTimings::Phase phase, double secs); 116 117 virtual void print_thresholds(); 118 119 virtual bool should_start_normal_gc() const = 0; 120 121 virtual bool should_start_update_refs(); 122 123 virtual bool update_refs() const; 124 125 virtual bool should_degenerate_cycle(); 126 127 virtual void record_success_concurrent(); 128 129 virtual void record_success_degenerated(); 130 131 virtual void record_success_full(); 132 133 virtual void record_allocation_failure_gc(); 134 135 virtual void record_explicit_gc(); 136 137 virtual void record_peak_occupancy(); 138 139 virtual void start_choose_collection_set() { 140 } 141 virtual void end_choose_collection_set() { 142 } 143 144 virtual void choose_collection_set(ShenandoahCollectionSet* collection_set); 145 146 virtual bool should_process_references(); 147 148 virtual bool should_unload_classes(); 149 150 virtual const char* name() = 0; 151 virtual bool is_diagnostic() = 0; 152 virtual bool is_experimental() = 0; 153 virtual void initialize(); 154 155 }; 156 157 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHHEURISTICS_HPP