1/*
2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
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24
25#ifndef SHARE_VM_GC_G1_G1POLICY_HPP
26#define SHARE_VM_GC_G1_G1POLICY_HPP
27
28#include "gc/g1/g1CollectorState.hpp"
29#include "gc/g1/g1GCPhaseTimes.hpp"
30#include "gc/g1/g1InCSetState.hpp"
31#include "gc/g1/g1InitialMarkToMixedTimeTracker.hpp"
32#include "gc/g1/g1MMUTracker.hpp"
33#include "gc/g1/g1Predictions.hpp"
34#include "gc/g1/g1YoungGenSizer.hpp"
35#include "gc/shared/gcCause.hpp"
36#include "utilities/pair.hpp"
37
38// A G1Policy makes policy decisions that determine the
39// characteristics of the collector.  Examples include:
40//   * choice of collection set.
41//   * when to collect.
42
43class HeapRegion;
44class G1CollectionSet;
45class CollectionSetChooser;
46class G1IHOPControl;
47class G1Analytics;
48class G1SurvivorRegions;
49class G1YoungGenSizer;
50
51class G1Policy: public CHeapObj<mtGC> {
52public:
53  virtual const G1Predictions& predictor() const = 0;
54  virtual const G1Analytics* analytics()   const = 0;
55
56  // Add the given number of bytes to the total number of allocated bytes in the old gen.
57  virtual void add_bytes_allocated_in_old_since_last_gc(size_t bytes) = 0;
58
59  // Accessors
60
61  virtual void set_region_eden(HeapRegion* hr) = 0;
62  virtual void set_region_survivor(HeapRegion* hr) = 0;
63
64  virtual void record_max_rs_lengths(size_t rs_lengths) = 0;
65
66  virtual double predict_base_elapsed_time_ms(size_t pending_cards) const = 0;
67  virtual double predict_base_elapsed_time_ms(size_t pending_cards,
68                                              size_t scanned_cards) const = 0;
69
70  virtual double predict_region_elapsed_time_ms(HeapRegion* hr, bool for_young_gc) const = 0;
71
72  virtual void cset_regions_freed() = 0;
73
74  virtual G1MMUTracker* mmu_tracker() = 0;
75
76  virtual const G1MMUTracker* mmu_tracker() const = 0;
77
78  virtual double max_pause_time_ms() const = 0;
79
80  virtual size_t pending_cards() const = 0;
81
82  // Calculate the minimum number of old regions we'll add to the CSet
83  // during a mixed GC.
84  virtual uint calc_min_old_cset_length() const = 0;
85
86  // Calculate the maximum number of old regions we'll add to the CSet
87  // during a mixed GC.
88  virtual uint calc_max_old_cset_length() const = 0;
89
90  // Returns the given amount of uncollected reclaimable space
91  // as a percentage of the current heap capacity.
92  virtual double reclaimable_bytes_perc(size_t reclaimable_bytes) const = 0;
93
94  virtual ~G1Policy() {}
95
96  virtual G1CollectorState* collector_state() const = 0;
97
98  virtual G1GCPhaseTimes* phase_times() const = 0;
99
100  // Check the current value of the young list RSet lengths and
101  // compare it against the last prediction. If the current value is
102  // higher, recalculate the young list target length prediction.
103  virtual void revise_young_list_target_length_if_necessary(size_t rs_lengths) = 0;
104
105  // This should be called after the heap is resized.
106  virtual void record_new_heap_size(uint new_number_of_regions) = 0;
107
108  virtual void init(G1CollectedHeap* g1h, G1CollectionSet* collection_set) = 0;
109
110  virtual void note_gc_start() = 0;
111
112  virtual bool need_to_start_conc_mark(const char* source, size_t alloc_word_size = 0) = 0;
113
114  // Record the start and end of an evacuation pause.
115  virtual void record_collection_pause_start(double start_time_sec) = 0;
116  virtual void record_collection_pause_end(double pause_time_ms, size_t cards_scanned, size_t heap_used_bytes_before_gc) = 0;
117
118  // Record the start and end of a full collection.
119  virtual void record_full_collection_start() = 0;
120  virtual void record_full_collection_end() = 0;
121
122  virtual jlong collection_pause_end_millis() = 0;
123
124  // Must currently be called while the world is stopped.
125  virtual void record_concurrent_mark_init_end(double mark_init_elapsed_time_ms) = 0;
126
127  // Record start and end of remark.
128  virtual void record_concurrent_mark_remark_start() = 0;
129  virtual void record_concurrent_mark_remark_end() = 0;
130
131  // Record start, end, and completion of cleanup.
132  virtual void record_concurrent_mark_cleanup_start() = 0;
133  virtual void record_concurrent_mark_cleanup_end() = 0;
134  virtual void record_concurrent_mark_cleanup_completed() = 0;
135
136  virtual void print_phases() = 0;
137
138  // Record how much space we copied during a GC. This is typically
139  // called when a GC alloc region is being retired.
140  virtual void record_bytes_copied_during_gc(size_t bytes) = 0;
141
142  // The amount of space we copied during a GC.
143  virtual size_t bytes_copied_during_gc() const = 0;
144
145  virtual void finalize_collection_set(double target_pause_time_ms, G1SurvivorRegions* survivor) = 0;
146
147  // This sets the initiate_conc_mark_if_possible() flag to start a
148  // new cycle, as long as we are not already in one. It's best if it
149  // is called during a safepoint when the test whether a cycle is in
150  // progress or not is stable.
151  virtual bool force_initial_mark_if_outside_cycle(GCCause::Cause gc_cause) = 0;
152
153  // This is called at the very beginning of an evacuation pause (it
154  // has to be the first thing that the pause does). If
155  // initiate_conc_mark_if_possible() is true, and the concurrent
156  // marking thread has completed its work during the previous cycle,
157  // it will set during_initial_mark_pause() to so that the pause does
158  // the initial-mark work and start a marking cycle.
159  virtual void decide_on_conc_mark_initiation() = 0;
160
161
162  virtual void finished_recalculating_age_indexes(bool is_survivors) = 0;
163
164  virtual void transfer_survivors_to_cset(const G1SurvivorRegions* survivors) = 0;
165
166  virtual size_t young_list_target_length() const = 0;
167
168  virtual bool should_allocate_mutator_region() const = 0;
169
170  virtual bool can_expand_young_list() const = 0;
171
172  virtual uint young_list_max_length() const = 0;
173
174  virtual bool adaptive_young_list_length() const = 0;
175
176  virtual bool should_process_references() const = 0;
177
178  virtual uint tenuring_threshold() const = 0;
179  virtual uint max_survivor_regions() = 0;
180
181  virtual void note_start_adding_survivor_regions() = 0;
182
183  virtual void note_stop_adding_survivor_regions() = 0;
184
185  virtual void record_age_table(AgeTable* age_table) = 0;
186  virtual void print_age_table() = 0;
187protected:
188  virtual size_t desired_survivor_size() const = 0;
189};
190
191#endif // SHARE_VM_GC_G1_G1POLICY_HPP
192