| /* |
| * Copyright (c) 2001, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_VM_GC_G1_G1COLLECTORPOLICY_HPP |
| #define SHARE_VM_GC_G1_G1COLLECTORPOLICY_HPP |
| |
| #include "gc/g1/collectionSetChooser.hpp" |
| #include "gc/g1/g1CollectorState.hpp" |
| #include "gc/g1/g1GCPhaseTimes.hpp" |
| #include "gc/g1/g1InCSetState.hpp" |
| #include "gc/g1/g1InitialMarkToMixedTimeTracker.hpp" |
| #include "gc/g1/g1MMUTracker.hpp" |
| #include "gc/g1/g1Predictions.hpp" |
| #include "gc/shared/collectorPolicy.hpp" |
| #include "utilities/pair.hpp" |
| |
| // A G1CollectorPolicy makes policy decisions that determine the |
| // characteristics of the collector. Examples include: |
| // * choice of collection set. |
| // * when to collect. |
| |
| class HeapRegion; |
| class CollectionSetChooser; |
| class G1IHOPControl; |
| class G1YoungGenSizer; |
| |
| class G1CollectorPolicy: public CollectorPolicy { |
| private: |
| G1IHOPControl* _ihop_control; |
| |
| G1IHOPControl* create_ihop_control() const; |
| // Update the IHOP control with necessary statistics. |
| void update_ihop_prediction(double mutator_time_s, |
| size_t mutator_alloc_bytes, |
| size_t young_gen_size); |
| void report_ihop_statistics(); |
| |
| G1Predictions _predictor; |
| |
| double get_new_prediction(TruncatedSeq const* seq) const; |
| size_t get_new_size_prediction(TruncatedSeq const* seq) const; |
| |
| G1MMUTracker* _mmu_tracker; |
| |
| void initialize_alignments(); |
| void initialize_flags(); |
| |
| CollectionSetChooser* _cset_chooser; |
| |
| double _full_collection_start_sec; |
| |
| // These exclude marking times. |
| TruncatedSeq* _recent_gc_times_ms; |
| |
| TruncatedSeq* _concurrent_mark_remark_times_ms; |
| TruncatedSeq* _concurrent_mark_cleanup_times_ms; |
| |
| // Ratio check data for determining if heap growth is necessary. |
| uint _ratio_over_threshold_count; |
| double _ratio_over_threshold_sum; |
| uint _pauses_since_start; |
| |
| uint _young_list_target_length; |
| uint _young_list_fixed_length; |
| |
| // The max number of regions we can extend the eden by while the GC |
| // locker is active. This should be >= _young_list_target_length; |
| uint _young_list_max_length; |
| |
| SurvRateGroup* _short_lived_surv_rate_group; |
| SurvRateGroup* _survivor_surv_rate_group; |
| // add here any more surv rate groups |
| |
| double _gc_overhead_perc; |
| |
| double _reserve_factor; |
| uint _reserve_regions; |
| |
| enum PredictionConstants { |
| TruncatedSeqLength = 10, |
| NumPrevPausesForHeuristics = 10, |
| // MinOverThresholdForGrowth must be less than NumPrevPausesForHeuristics, |
| // representing the minimum number of pause time ratios that exceed |
| // GCTimeRatio before a heap expansion will be triggered. |
| MinOverThresholdForGrowth = 4 |
| }; |
| |
| TruncatedSeq* _alloc_rate_ms_seq; |
| double _prev_collection_pause_end_ms; |
| |
| TruncatedSeq* _rs_length_diff_seq; |
| TruncatedSeq* _cost_per_card_ms_seq; |
| TruncatedSeq* _cost_scan_hcc_seq; |
| TruncatedSeq* _young_cards_per_entry_ratio_seq; |
| TruncatedSeq* _mixed_cards_per_entry_ratio_seq; |
| TruncatedSeq* _cost_per_entry_ms_seq; |
| TruncatedSeq* _mixed_cost_per_entry_ms_seq; |
| TruncatedSeq* _cost_per_byte_ms_seq; |
| TruncatedSeq* _constant_other_time_ms_seq; |
| TruncatedSeq* _young_other_cost_per_region_ms_seq; |
| TruncatedSeq* _non_young_other_cost_per_region_ms_seq; |
| |
| TruncatedSeq* _pending_cards_seq; |
| TruncatedSeq* _rs_lengths_seq; |
| |
| TruncatedSeq* _cost_per_byte_ms_during_cm_seq; |
| |
| G1YoungGenSizer* _young_gen_sizer; |
| |
| uint _eden_cset_region_length; |
| uint _survivor_cset_region_length; |
| uint _old_cset_region_length; |
| |
| void init_cset_region_lengths(uint eden_cset_region_length, |
| uint survivor_cset_region_length); |
| |
| uint eden_cset_region_length() const { return _eden_cset_region_length; } |
| uint survivor_cset_region_length() const { return _survivor_cset_region_length; } |
| uint old_cset_region_length() const { return _old_cset_region_length; } |
| |
| uint _free_regions_at_end_of_collection; |
| |
| size_t _recorded_rs_lengths; |
| size_t _max_rs_lengths; |
| |
| size_t _rs_lengths_prediction; |
| |
| #ifndef PRODUCT |
| bool verify_young_ages(HeapRegion* head, SurvRateGroup *surv_rate_group); |
| #endif // PRODUCT |
| |
| void adjust_concurrent_refinement(double update_rs_time, |
| double update_rs_processed_buffers, |
| double goal_ms); |
| |
| double _pause_time_target_ms; |
| |
| size_t _pending_cards; |
| |
| // The amount of allocated bytes in old gen during the last mutator and the following |
| // young GC phase. |
| size_t _bytes_allocated_in_old_since_last_gc; |
| |
| G1InitialMarkToMixedTimeTracker _initial_mark_to_mixed; |
| public: |
| const G1Predictions& predictor() const { return _predictor; } |
| |
| // Add the given number of bytes to the total number of allocated bytes in the old gen. |
| void add_bytes_allocated_in_old_since_last_gc(size_t bytes) { _bytes_allocated_in_old_since_last_gc += bytes; } |
| |
| // Accessors |
| |
| void set_region_eden(HeapRegion* hr, int young_index_in_cset) { |
| hr->set_eden(); |
| hr->install_surv_rate_group(_short_lived_surv_rate_group); |
| hr->set_young_index_in_cset(young_index_in_cset); |
| } |
| |
| void set_region_survivor(HeapRegion* hr, int young_index_in_cset) { |
| assert(hr->is_survivor(), "pre-condition"); |
| hr->install_surv_rate_group(_survivor_surv_rate_group); |
| hr->set_young_index_in_cset(young_index_in_cset); |
| } |
| |
| #ifndef PRODUCT |
| bool verify_young_ages(); |
| #endif // PRODUCT |
| |
| void record_max_rs_lengths(size_t rs_lengths) { |
| _max_rs_lengths = rs_lengths; |
| } |
| |
| size_t predict_rs_length_diff() const; |
| |
| double predict_alloc_rate_ms() const; |
| |
| double predict_cost_per_card_ms() const; |
| |
| double predict_scan_hcc_ms() const; |
| |
| double predict_rs_update_time_ms(size_t pending_cards) const; |
| |
| double predict_young_cards_per_entry_ratio() const; |
| |
| double predict_mixed_cards_per_entry_ratio() const; |
| |
| size_t predict_young_card_num(size_t rs_length) const; |
| |
| size_t predict_non_young_card_num(size_t rs_length) const; |
| |
| double predict_rs_scan_time_ms(size_t card_num) const; |
| |
| double predict_mixed_rs_scan_time_ms(size_t card_num) const; |
| |
| double predict_object_copy_time_ms_during_cm(size_t bytes_to_copy) const; |
| |
| double predict_object_copy_time_ms(size_t bytes_to_copy) const; |
| |
| double predict_constant_other_time_ms() const; |
| |
| double predict_young_other_time_ms(size_t young_num) const; |
| |
| double predict_non_young_other_time_ms(size_t non_young_num) const; |
| |
| double predict_base_elapsed_time_ms(size_t pending_cards) const; |
| double predict_base_elapsed_time_ms(size_t pending_cards, |
| size_t scanned_cards) const; |
| size_t predict_bytes_to_copy(HeapRegion* hr) const; |
| double predict_region_elapsed_time_ms(HeapRegion* hr, bool for_young_gc) const; |
| |
| void set_recorded_rs_lengths(size_t rs_lengths); |
| |
| uint cset_region_length() const { return young_cset_region_length() + |
| old_cset_region_length(); } |
| uint young_cset_region_length() const { return eden_cset_region_length() + |
| survivor_cset_region_length(); } |
| |
| double predict_survivor_regions_evac_time() const; |
| |
| bool should_update_surv_rate_group_predictors() { |
| return collector_state()->last_gc_was_young() && !collector_state()->in_marking_window(); |
| } |
| |
| void cset_regions_freed() { |
| bool update = should_update_surv_rate_group_predictors(); |
| |
| _short_lived_surv_rate_group->all_surviving_words_recorded(update); |
| _survivor_surv_rate_group->all_surviving_words_recorded(update); |
| } |
| |
| G1MMUTracker* mmu_tracker() { |
| return _mmu_tracker; |
| } |
| |
| const G1MMUTracker* mmu_tracker() const { |
| return _mmu_tracker; |
| } |
| |
| double max_pause_time_ms() const { |
| return _mmu_tracker->max_gc_time() * 1000.0; |
| } |
| |
| double predict_remark_time_ms() const; |
| |
| double predict_cleanup_time_ms() const; |
| |
| // Returns an estimate of the survival rate of the region at yg-age |
| // "yg_age". |
| double predict_yg_surv_rate(int age, SurvRateGroup* surv_rate_group) const; |
| |
| double predict_yg_surv_rate(int age) const; |
| |
| double accum_yg_surv_rate_pred(int age) const; |
| |
| protected: |
| virtual double average_time_ms(G1GCPhaseTimes::GCParPhases phase) const; |
| virtual double other_time_ms(double pause_time_ms) const; |
| |
| double young_other_time_ms() const; |
| double non_young_other_time_ms() const; |
| double constant_other_time_ms(double pause_time_ms) const; |
| |
| CollectionSetChooser* cset_chooser() const { |
| return _cset_chooser; |
| } |
| |
| private: |
| // Statistics kept per GC stoppage, pause or full. |
| TruncatedSeq* _recent_prev_end_times_for_all_gcs_sec; |
| |
| // Add a new GC of the given duration and end time to the record. |
| void update_recent_gc_times(double end_time_sec, double elapsed_ms); |
| |
| // The head of the list (via "next_in_collection_set()") representing the |
| // current collection set. Set from the incrementally built collection |
| // set at the start of the pause. |
| HeapRegion* _collection_set; |
| |
| // The number of bytes in the collection set before the pause. Set from |
| // the incrementally built collection set at the start of an evacuation |
| // pause, and incremented in finalize_old_cset_part() when adding old regions |
| // (if any) to the collection set. |
| size_t _collection_set_bytes_used_before; |
| |
| // The number of bytes copied during the GC. |
| size_t _bytes_copied_during_gc; |
| |
| // The associated information that is maintained while the incremental |
| // collection set is being built with young regions. Used to populate |
| // the recorded info for the evacuation pause. |
| |
| enum CSetBuildType { |
| Active, // We are actively building the collection set |
| Inactive // We are not actively building the collection set |
| }; |
| |
| CSetBuildType _inc_cset_build_state; |
| |
| // The head of the incrementally built collection set. |
| HeapRegion* _inc_cset_head; |
| |
| // The tail of the incrementally built collection set. |
| HeapRegion* _inc_cset_tail; |
| |
| // The number of bytes in the incrementally built collection set. |
| // Used to set _collection_set_bytes_used_before at the start of |
| // an evacuation pause. |
| size_t _inc_cset_bytes_used_before; |
| |
| // The RSet lengths recorded for regions in the CSet. It is updated |
| // by the thread that adds a new region to the CSet. We assume that |
| // only one thread can be allocating a new CSet region (currently, |
| // it does so after taking the Heap_lock) hence no need to |
| // synchronize updates to this field. |
| size_t _inc_cset_recorded_rs_lengths; |
| |
| // A concurrent refinement thread periodically samples the young |
| // region RSets and needs to update _inc_cset_recorded_rs_lengths as |
| // the RSets grow. Instead of having to synchronize updates to that |
| // field we accumulate them in this field and add it to |
| // _inc_cset_recorded_rs_lengths_diffs at the start of a GC. |
| ssize_t _inc_cset_recorded_rs_lengths_diffs; |
| |
| // The predicted elapsed time it will take to collect the regions in |
| // the CSet. This is updated by the thread that adds a new region to |
| // the CSet. See the comment for _inc_cset_recorded_rs_lengths about |
| // MT-safety assumptions. |
| double _inc_cset_predicted_elapsed_time_ms; |
| |
| // See the comment for _inc_cset_recorded_rs_lengths_diffs. |
| double _inc_cset_predicted_elapsed_time_ms_diffs; |
| |
| // Stash a pointer to the g1 heap. |
| G1CollectedHeap* _g1; |
| |
| G1GCPhaseTimes* _phase_times; |
| |
| // The ratio of gc time to elapsed time, computed over recent pauses, |
| // and the ratio for just the last pause. |
| double _recent_avg_pause_time_ratio; |
| double _last_pause_time_ratio; |
| |
| double recent_avg_pause_time_ratio() const { |
| return _recent_avg_pause_time_ratio; |
| } |
| |
| // This set of variables tracks the collector efficiency, in order to |
| // determine whether we should initiate a new marking. |
| double _mark_remark_start_sec; |
| double _mark_cleanup_start_sec; |
| |
| // Updates the internal young list maximum and target lengths. Returns the |
| // unbounded young list target length. |
| uint update_young_list_max_and_target_length(); |
| uint update_young_list_max_and_target_length(size_t rs_lengths); |
| |
| // Update the young list target length either by setting it to the |
| // desired fixed value or by calculating it using G1's pause |
| // prediction model. If no rs_lengths parameter is passed, predict |
| // the RS lengths using the prediction model, otherwise use the |
| // given rs_lengths as the prediction. |
| // Returns the unbounded young list target length. |
| uint update_young_list_target_length(size_t rs_lengths); |
| |
| // Calculate and return the minimum desired young list target |
| // length. This is the minimum desired young list length according |
| // to the user's inputs. |
| uint calculate_young_list_desired_min_length(uint base_min_length) const; |
| |
| // Calculate and return the maximum desired young list target |
| // length. This is the maximum desired young list length according |
| // to the user's inputs. |
| uint calculate_young_list_desired_max_length() const; |
| |
| // Calculate and return the maximum young list target length that |
| // can fit into the pause time goal. The parameters are: rs_lengths |
| // represent the prediction of how large the young RSet lengths will |
| // be, base_min_length is the already existing number of regions in |
| // the young list, min_length and max_length are the desired min and |
| // max young list length according to the user's inputs. |
| uint calculate_young_list_target_length(size_t rs_lengths, |
| uint base_min_length, |
| uint desired_min_length, |
| uint desired_max_length) const; |
| |
| // Result of the bounded_young_list_target_length() method, containing both the |
| // bounded as well as the unbounded young list target lengths in this order. |
| typedef Pair<uint, uint, StackObj> YoungTargetLengths; |
| YoungTargetLengths young_list_target_lengths(size_t rs_lengths) const; |
| |
| void update_rs_lengths_prediction(); |
| void update_rs_lengths_prediction(size_t prediction); |
| |
| // Calculate and return chunk size (in number of regions) for parallel |
| // concurrent mark cleanup. |
| uint calculate_parallel_work_chunk_size(uint n_workers, uint n_regions) const; |
| |
| // Check whether a given young length (young_length) fits into the |
| // given target pause time and whether the prediction for the amount |
| // of objects to be copied for the given length will fit into the |
| // given free space (expressed by base_free_regions). It is used by |
| // calculate_young_list_target_length(). |
| bool predict_will_fit(uint young_length, double base_time_ms, |
| uint base_free_regions, double target_pause_time_ms) const; |
| |
| // Calculate the minimum number of old regions we'll add to the CSet |
| // during a mixed GC. |
| uint calc_min_old_cset_length() const; |
| |
| // Calculate the maximum number of old regions we'll add to the CSet |
| // during a mixed GC. |
| uint calc_max_old_cset_length() const; |
| |
| // Returns the given amount of uncollected reclaimable space |
| // as a percentage of the current heap capacity. |
| double reclaimable_bytes_perc(size_t reclaimable_bytes) const; |
| |
| // Sets up marking if proper conditions are met. |
| void maybe_start_marking(); |
| |
| // The kind of STW pause. |
| enum PauseKind { |
| FullGC, |
| YoungOnlyGC, |
| MixedGC, |
| LastYoungGC, |
| InitialMarkGC, |
| Cleanup, |
| Remark |
| }; |
| |
| // Calculate PauseKind from internal state. |
| PauseKind young_gc_pause_kind() const; |
| // Record the given STW pause with the given start and end times (in s). |
| void record_pause(PauseKind kind, double start, double end); |
| // Indicate that we aborted marking before doing any mixed GCs. |
| void abort_time_to_mixed_tracking(); |
| public: |
| |
| G1CollectorPolicy(); |
| |
| virtual ~G1CollectorPolicy(); |
| |
| virtual G1CollectorPolicy* as_g1_policy() { return this; } |
| |
| G1CollectorState* collector_state() const; |
| |
| G1GCPhaseTimes* phase_times() const { return _phase_times; } |
| |
| // Check the current value of the young list RSet lengths and |
| // compare it against the last prediction. If the current value is |
| // higher, recalculate the young list target length prediction. |
| void revise_young_list_target_length_if_necessary(size_t rs_lengths); |
| |
| // This should be called after the heap is resized. |
| void record_new_heap_size(uint new_number_of_regions); |
| |
| void init(); |
| |
| virtual void note_gc_start(uint num_active_workers); |
| |
| // Create jstat counters for the policy. |
| virtual void initialize_gc_policy_counters(); |
| |
| bool need_to_start_conc_mark(const char* source, size_t alloc_word_size = 0); |
| |
| bool about_to_start_mixed_phase() const; |
| |
| // Record the start and end of an evacuation pause. |
| void record_collection_pause_start(double start_time_sec); |
| void record_collection_pause_end(double pause_time_ms, size_t cards_scanned, size_t heap_used_bytes_before_gc); |
| |
| // Record the start and end of a full collection. |
| void record_full_collection_start(); |
| void record_full_collection_end(); |
| |
| // Must currently be called while the world is stopped. |
| void record_concurrent_mark_init_end(double mark_init_elapsed_time_ms); |
| |
| // Record start and end of remark. |
| void record_concurrent_mark_remark_start(); |
| void record_concurrent_mark_remark_end(); |
| |
| // Record start, end, and completion of cleanup. |
| void record_concurrent_mark_cleanup_start(); |
| void record_concurrent_mark_cleanup_end(); |
| void record_concurrent_mark_cleanup_completed(); |
| |
| virtual void print_phases(); |
| |
| // Record how much space we copied during a GC. This is typically |
| // called when a GC alloc region is being retired. |
| void record_bytes_copied_during_gc(size_t bytes) { |
| _bytes_copied_during_gc += bytes; |
| } |
| |
| // The amount of space we copied during a GC. |
| size_t bytes_copied_during_gc() const { |
| return _bytes_copied_during_gc; |
| } |
| |
| size_t collection_set_bytes_used_before() const { |
| return _collection_set_bytes_used_before; |
| } |
| |
| // Determine whether there are candidate regions so that the |
| // next GC should be mixed. The two action strings are used |
| // in the ergo output when the method returns true or false. |
| bool next_gc_should_be_mixed(const char* true_action_str, |
| const char* false_action_str) const; |
| |
| // Choose a new collection set. Marks the chosen regions as being |
| // "in_collection_set", and links them together. The head and number of |
| // the collection set are available via access methods. |
| double finalize_young_cset_part(double target_pause_time_ms); |
| virtual void finalize_old_cset_part(double time_remaining_ms); |
| |
| // The head of the list (via "next_in_collection_set()") representing the |
| // current collection set. |
| HeapRegion* collection_set() { return _collection_set; } |
| |
| void clear_collection_set() { _collection_set = NULL; } |
| |
| // Add old region "hr" to the CSet. |
| void add_old_region_to_cset(HeapRegion* hr); |
| |
| // Incremental CSet Support |
| |
| // The head of the incrementally built collection set. |
| HeapRegion* inc_cset_head() { return _inc_cset_head; } |
| |
| // The tail of the incrementally built collection set. |
| HeapRegion* inc_set_tail() { return _inc_cset_tail; } |
| |
| // Initialize incremental collection set info. |
| void start_incremental_cset_building(); |
| |
| // Perform any final calculations on the incremental CSet fields |
| // before we can use them. |
| void finalize_incremental_cset_building(); |
| |
| void clear_incremental_cset() { |
| _inc_cset_head = NULL; |
| _inc_cset_tail = NULL; |
| } |
| |
| // Stop adding regions to the incremental collection set |
| void stop_incremental_cset_building() { _inc_cset_build_state = Inactive; } |
| |
| // Add information about hr to the aggregated information for the |
| // incrementally built collection set. |
| void add_to_incremental_cset_info(HeapRegion* hr, size_t rs_length); |
| |
| // Update information about hr in the aggregated information for |
| // the incrementally built collection set. |
| void update_incremental_cset_info(HeapRegion* hr, size_t new_rs_length); |
| |
| private: |
| // Update the incremental cset information when adding a region |
| // (should not be called directly). |
| void add_region_to_incremental_cset_common(HeapRegion* hr); |
| |
| // Set the state to start a concurrent marking cycle and clear |
| // _initiate_conc_mark_if_possible because it has now been |
| // acted on. |
| void initiate_conc_mark(); |
| |
| public: |
| // Add hr to the LHS of the incremental collection set. |
| void add_region_to_incremental_cset_lhs(HeapRegion* hr); |
| |
| // Add hr to the RHS of the incremental collection set. |
| void add_region_to_incremental_cset_rhs(HeapRegion* hr); |
| |
| #ifndef PRODUCT |
| void print_collection_set(HeapRegion* list_head, outputStream* st); |
| #endif // !PRODUCT |
| |
| // This sets the initiate_conc_mark_if_possible() flag to start a |
| // new cycle, as long as we are not already in one. It's best if it |
| // is called during a safepoint when the test whether a cycle is in |
| // progress or not is stable. |
| bool force_initial_mark_if_outside_cycle(GCCause::Cause gc_cause); |
| |
| // This is called at the very beginning of an evacuation pause (it |
| // has to be the first thing that the pause does). If |
| // initiate_conc_mark_if_possible() is true, and the concurrent |
| // marking thread has completed its work during the previous cycle, |
| // it will set during_initial_mark_pause() to so that the pause does |
| // the initial-mark work and start a marking cycle. |
| void decide_on_conc_mark_initiation(); |
| |
| // If an expansion would be appropriate, because recent GC overhead had |
| // exceeded the desired limit, return an amount to expand by. |
| virtual size_t expansion_amount(); |
| |
| // Clear ratio tracking data used by expansion_amount(). |
| void clear_ratio_check_data(); |
| |
| // Print stats on young survival ratio |
| void print_yg_surv_rate_info() const; |
| |
| void finished_recalculating_age_indexes(bool is_survivors) { |
| if (is_survivors) { |
| _survivor_surv_rate_group->finished_recalculating_age_indexes(); |
| } else { |
| _short_lived_surv_rate_group->finished_recalculating_age_indexes(); |
| } |
| // do that for any other surv rate groups |
| } |
| |
| size_t young_list_target_length() const { return _young_list_target_length; } |
| |
| bool is_young_list_full() const; |
| |
| bool can_expand_young_list() const; |
| |
| uint young_list_max_length() const { |
| return _young_list_max_length; |
| } |
| |
| bool adaptive_young_list_length() const; |
| |
| virtual bool should_process_references() const { |
| return true; |
| } |
| |
| private: |
| // |
| // Survivor regions policy. |
| // |
| |
| // Current tenuring threshold, set to 0 if the collector reaches the |
| // maximum amount of survivors regions. |
| uint _tenuring_threshold; |
| |
| // The limit on the number of regions allocated for survivors. |
| uint _max_survivor_regions; |
| |
| // For reporting purposes. |
| // The value of _heap_bytes_before_gc is also used to calculate |
| // the cost of copying. |
| |
| // The amount of survivor regions after a collection. |
| uint _recorded_survivor_regions; |
| // List of survivor regions. |
| HeapRegion* _recorded_survivor_head; |
| HeapRegion* _recorded_survivor_tail; |
| |
| AgeTable _survivors_age_table; |
| |
| public: |
| uint tenuring_threshold() const { return _tenuring_threshold; } |
| |
| uint max_survivor_regions() { |
| return _max_survivor_regions; |
| } |
| |
| static const uint REGIONS_UNLIMITED = (uint) -1; |
| |
| uint max_regions(InCSetState dest) const { |
| switch (dest.value()) { |
| case InCSetState::Young: |
| return _max_survivor_regions; |
| case InCSetState::Old: |
| return REGIONS_UNLIMITED; |
| default: |
| assert(false, "Unknown dest state: " CSETSTATE_FORMAT, dest.value()); |
| break; |
| } |
| // keep some compilers happy |
| return 0; |
| } |
| |
| void note_start_adding_survivor_regions() { |
| _survivor_surv_rate_group->start_adding_regions(); |
| } |
| |
| void note_stop_adding_survivor_regions() { |
| _survivor_surv_rate_group->stop_adding_regions(); |
| } |
| |
| void record_survivor_regions(uint regions, |
| HeapRegion* head, |
| HeapRegion* tail) { |
| _recorded_survivor_regions = regions; |
| _recorded_survivor_head = head; |
| _recorded_survivor_tail = tail; |
| } |
| |
| uint recorded_survivor_regions() const { |
| return _recorded_survivor_regions; |
| } |
| |
| void record_age_table(AgeTable* age_table) { |
| _survivors_age_table.merge(age_table); |
| } |
| |
| void update_max_gc_locker_expansion(); |
| |
| // Calculates survivor space parameters. |
| void update_survivors_policy(); |
| |
| virtual void post_heap_initialize(); |
| }; |
| |
| #endif // SHARE_VM_GC_G1_G1COLLECTORPOLICY_HPP |