Mercurial > hg > truffle
view src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp @ 4150:c78bace5086a
start work on integrating old hooks into mx, work on sanity checks
introduce a DB class to access the bench DB in an easier way (create benchmarks and benchmark values automatically in the DB)
author | Gilles Duboscq <gilles.m.duboscq@gmail.com> |
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date | Tue, 20 Dec 2011 15:34:43 +0100 |
parents | dc467e8b2c5e |
children | 41406797186b |
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/* * Copyright (c) 2001, 2011, 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_IMPLEMENTATION_G1_G1COLLECTORPOLICY_HPP #define SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTORPOLICY_HPP #include "gc_implementation/g1/collectionSetChooser.hpp" #include "gc_implementation/g1/g1MMUTracker.hpp" #include "memory/collectorPolicy.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; // Yes, this is a bit unpleasant... but it saves replicating the same thing // over and over again and introducing subtle problems through small typos and // cutting and pasting mistakes. The macros below introduces a number // sequnce into the following two classes and the methods that access it. #define define_num_seq(name) \ private: \ NumberSeq _all_##name##_times_ms; \ public: \ void record_##name##_time_ms(double ms) { \ _all_##name##_times_ms.add(ms); \ } \ NumberSeq* get_##name##_seq() { \ return &_all_##name##_times_ms; \ } class MainBodySummary; class PauseSummary: public CHeapObj { define_num_seq(total) define_num_seq(other) public: virtual MainBodySummary* main_body_summary() { return NULL; } }; class MainBodySummary: public CHeapObj { define_num_seq(satb_drain) // optional define_num_seq(parallel) // parallel only define_num_seq(ext_root_scan) define_num_seq(mark_stack_scan) define_num_seq(update_rs) define_num_seq(scan_rs) define_num_seq(obj_copy) define_num_seq(termination) // parallel only define_num_seq(parallel_other) // parallel only define_num_seq(mark_closure) define_num_seq(clear_ct) }; class Summary: public PauseSummary, public MainBodySummary { public: virtual MainBodySummary* main_body_summary() { return this; } }; class G1CollectorPolicy: public CollectorPolicy { private: // either equal to the number of parallel threads, if ParallelGCThreads // has been set, or 1 otherwise int _parallel_gc_threads; // The number of GC threads currently active. uintx _no_of_gc_threads; enum SomePrivateConstants { NumPrevPausesForHeuristics = 10 }; G1MMUTracker* _mmu_tracker; void initialize_flags(); void initialize_all() { initialize_flags(); initialize_size_info(); initialize_perm_generation(PermGen::MarkSweepCompact); } CollectionSetChooser* _collectionSetChooser; double _cur_collection_start_sec; size_t _cur_collection_pause_used_at_start_bytes; size_t _cur_collection_pause_used_regions_at_start; size_t _prev_collection_pause_used_at_end_bytes; double _cur_collection_par_time_ms; double _cur_satb_drain_time_ms; double _cur_clear_ct_time_ms; double _cur_ref_proc_time_ms; double _cur_ref_enq_time_ms; #ifndef PRODUCT // Card Table Count Cache stats double _min_clear_cc_time_ms; // min double _max_clear_cc_time_ms; // max double _cur_clear_cc_time_ms; // clearing time during current pause double _cum_clear_cc_time_ms; // cummulative clearing time jlong _num_cc_clears; // number of times the card count cache has been cleared #endif // These exclude marking times. TruncatedSeq* _recent_gc_times_ms; TruncatedSeq* _concurrent_mark_remark_times_ms; TruncatedSeq* _concurrent_mark_cleanup_times_ms; Summary* _summary; NumberSeq* _all_pause_times_ms; NumberSeq* _all_full_gc_times_ms; double _stop_world_start; NumberSeq* _all_stop_world_times_ms; NumberSeq* _all_yield_times_ms; int _aux_num; NumberSeq* _all_aux_times_ms; double* _cur_aux_start_times_ms; double* _cur_aux_times_ms; bool* _cur_aux_times_set; double* _par_last_gc_worker_start_times_ms; double* _par_last_ext_root_scan_times_ms; double* _par_last_mark_stack_scan_times_ms; double* _par_last_update_rs_times_ms; double* _par_last_update_rs_processed_buffers; double* _par_last_scan_rs_times_ms; double* _par_last_obj_copy_times_ms; double* _par_last_termination_times_ms; double* _par_last_termination_attempts; double* _par_last_gc_worker_end_times_ms; double* _par_last_gc_worker_times_ms; // Each workers 'other' time i.e. the elapsed time of the parallel // phase of the pause minus the sum of the individual sub-phase // times for a given worker thread. double* _par_last_gc_worker_other_times_ms; // indicates whether we are in full young or partially young GC mode bool _full_young_gcs; // if true, then it tries to dynamically adjust the length of the // young list bool _adaptive_young_list_length; size_t _young_list_target_length; size_t _young_list_fixed_length; size_t _prev_eden_capacity; // used for logging // The max number of regions we can extend the eden by while the GC // locker is active. This should be >= _young_list_target_length; size_t _young_list_max_length; bool _last_young_gc_full; unsigned _full_young_pause_num; unsigned _partial_young_pause_num; bool _during_marking; bool _in_marking_window; bool _in_marking_window_im; 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; size_t _reserve_regions; bool during_marking() { return _during_marking; } private: enum PredictionConstants { TruncatedSeqLength = 10 }; TruncatedSeq* _alloc_rate_ms_seq; double _prev_collection_pause_end_ms; TruncatedSeq* _pending_card_diff_seq; TruncatedSeq* _rs_length_diff_seq; TruncatedSeq* _cost_per_card_ms_seq; TruncatedSeq* _fully_young_cards_per_entry_ratio_seq; TruncatedSeq* _partially_young_cards_per_entry_ratio_seq; TruncatedSeq* _cost_per_entry_ms_seq; TruncatedSeq* _partially_young_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; TruncatedSeq* _young_gc_eff_seq; bool _using_new_ratio_calculations; size_t _min_desired_young_length; // as set on the command line or default calculations size_t _max_desired_young_length; // as set on the command line or default calculations size_t _eden_cset_region_length; size_t _survivor_cset_region_length; size_t _old_cset_region_length; void init_cset_region_lengths(size_t eden_cset_region_length, size_t survivor_cset_region_length); size_t eden_cset_region_length() { return _eden_cset_region_length; } size_t survivor_cset_region_length() { return _survivor_cset_region_length; } size_t old_cset_region_length() { return _old_cset_region_length; } size_t _free_regions_at_end_of_collection; size_t _recorded_rs_lengths; size_t _max_rs_lengths; double _recorded_young_free_cset_time_ms; double _recorded_non_young_free_cset_time_ms; double _sigma; double _expensive_region_limit_ms; size_t _rs_lengths_prediction; size_t _known_garbage_bytes; double _known_garbage_ratio; double sigma() { return _sigma; } // A function that prevents us putting too much stock in small sample // sets. Returns a number between 2.0 and 1.0, depending on the number // of samples. 5 or more samples yields one; fewer scales linearly from // 2.0 at 1 sample to 1.0 at 5. double confidence_factor(int samples) { if (samples > 4) return 1.0; else return 1.0 + sigma() * ((double)(5 - samples))/2.0; } double get_new_neg_prediction(TruncatedSeq* seq) { return seq->davg() - sigma() * seq->dsd(); } #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); uintx no_of_gc_threads() { return _no_of_gc_threads; } void set_no_of_gc_threads(uintx v) { _no_of_gc_threads = v; } double _pause_time_target_ms; double _recorded_young_cset_choice_time_ms; double _recorded_non_young_cset_choice_time_ms; size_t _pending_cards; size_t _max_pending_cards; public: // Accessors void set_region_eden(HeapRegion* hr, int young_index_in_cset) { hr->set_young(); 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_young() && 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 double get_new_prediction(TruncatedSeq* seq) { return MAX2(seq->davg() + sigma() * seq->dsd(), seq->davg() * confidence_factor(seq->num())); } void record_max_rs_lengths(size_t rs_lengths) { _max_rs_lengths = rs_lengths; } size_t predict_pending_card_diff() { double prediction = get_new_neg_prediction(_pending_card_diff_seq); if (prediction < 0.00001) return 0; else return (size_t) prediction; } size_t predict_pending_cards() { size_t max_pending_card_num = _g1->max_pending_card_num(); size_t diff = predict_pending_card_diff(); size_t prediction; if (diff > max_pending_card_num) prediction = max_pending_card_num; else prediction = max_pending_card_num - diff; return prediction; } size_t predict_rs_length_diff() { return (size_t) get_new_prediction(_rs_length_diff_seq); } double predict_alloc_rate_ms() { return get_new_prediction(_alloc_rate_ms_seq); } double predict_cost_per_card_ms() { return get_new_prediction(_cost_per_card_ms_seq); } double predict_rs_update_time_ms(size_t pending_cards) { return (double) pending_cards * predict_cost_per_card_ms(); } double predict_fully_young_cards_per_entry_ratio() { return get_new_prediction(_fully_young_cards_per_entry_ratio_seq); } double predict_partially_young_cards_per_entry_ratio() { if (_partially_young_cards_per_entry_ratio_seq->num() < 2) return predict_fully_young_cards_per_entry_ratio(); else return get_new_prediction(_partially_young_cards_per_entry_ratio_seq); } size_t predict_young_card_num(size_t rs_length) { return (size_t) ((double) rs_length * predict_fully_young_cards_per_entry_ratio()); } size_t predict_non_young_card_num(size_t rs_length) { return (size_t) ((double) rs_length * predict_partially_young_cards_per_entry_ratio()); } double predict_rs_scan_time_ms(size_t card_num) { if (full_young_gcs()) return (double) card_num * get_new_prediction(_cost_per_entry_ms_seq); else return predict_partially_young_rs_scan_time_ms(card_num); } double predict_partially_young_rs_scan_time_ms(size_t card_num) { if (_partially_young_cost_per_entry_ms_seq->num() < 3) return (double) card_num * get_new_prediction(_cost_per_entry_ms_seq); else return (double) card_num * get_new_prediction(_partially_young_cost_per_entry_ms_seq); } double predict_object_copy_time_ms_during_cm(size_t bytes_to_copy) { if (_cost_per_byte_ms_during_cm_seq->num() < 3) return 1.1 * (double) bytes_to_copy * get_new_prediction(_cost_per_byte_ms_seq); else return (double) bytes_to_copy * get_new_prediction(_cost_per_byte_ms_during_cm_seq); } double predict_object_copy_time_ms(size_t bytes_to_copy) { if (_in_marking_window && !_in_marking_window_im) return predict_object_copy_time_ms_during_cm(bytes_to_copy); else return (double) bytes_to_copy * get_new_prediction(_cost_per_byte_ms_seq); } double predict_constant_other_time_ms() { return get_new_prediction(_constant_other_time_ms_seq); } double predict_young_other_time_ms(size_t young_num) { return (double) young_num * get_new_prediction(_young_other_cost_per_region_ms_seq); } double predict_non_young_other_time_ms(size_t non_young_num) { return (double) non_young_num * get_new_prediction(_non_young_other_cost_per_region_ms_seq); } void check_if_region_is_too_expensive(double predicted_time_ms); double predict_young_collection_elapsed_time_ms(size_t adjustment); double predict_base_elapsed_time_ms(size_t pending_cards); double predict_base_elapsed_time_ms(size_t pending_cards, size_t scanned_cards); size_t predict_bytes_to_copy(HeapRegion* hr); double predict_region_elapsed_time_ms(HeapRegion* hr, bool young); void set_recorded_rs_lengths(size_t rs_lengths); size_t cset_region_length() { return young_cset_region_length() + old_cset_region_length(); } size_t young_cset_region_length() { return eden_cset_region_length() + survivor_cset_region_length(); } void record_young_free_cset_time_ms(double time_ms) { _recorded_young_free_cset_time_ms = time_ms; } void record_non_young_free_cset_time_ms(double time_ms) { _recorded_non_young_free_cset_time_ms = time_ms; } double predict_young_gc_eff() { return get_new_neg_prediction(_young_gc_eff_seq); } double predict_survivor_regions_evac_time(); void cset_regions_freed() { bool propagate = _last_young_gc_full && !_in_marking_window; _short_lived_surv_rate_group->all_surviving_words_recorded(propagate); _survivor_surv_rate_group->all_surviving_words_recorded(propagate); // also call it on any more surv rate groups } void set_known_garbage_bytes(size_t known_garbage_bytes) { _known_garbage_bytes = known_garbage_bytes; size_t heap_bytes = _g1->capacity(); _known_garbage_ratio = (double) _known_garbage_bytes / (double) heap_bytes; } void decrease_known_garbage_bytes(size_t known_garbage_bytes) { guarantee( _known_garbage_bytes >= known_garbage_bytes, "invariant" ); _known_garbage_bytes -= known_garbage_bytes; size_t heap_bytes = _g1->capacity(); _known_garbage_ratio = (double) _known_garbage_bytes / (double) heap_bytes; } G1MMUTracker* mmu_tracker() { return _mmu_tracker; } double max_pause_time_ms() { return _mmu_tracker->max_gc_time() * 1000.0; } double predict_remark_time_ms() { return get_new_prediction(_concurrent_mark_remark_times_ms); } double predict_cleanup_time_ms() { return get_new_prediction(_concurrent_mark_cleanup_times_ms); } // 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) { TruncatedSeq* seq = surv_rate_group->get_seq(age); if (seq->num() == 0) gclog_or_tty->print("BARF! age is %d", age); guarantee( seq->num() > 0, "invariant" ); double pred = get_new_prediction(seq); if (pred > 1.0) pred = 1.0; return pred; } double predict_yg_surv_rate(int age) { return predict_yg_surv_rate(age, _short_lived_surv_rate_group); } double accum_yg_surv_rate_pred(int age) { return _short_lived_surv_rate_group->accum_surv_rate_pred(age); } private: void print_stats(int level, const char* str, double value); void print_stats(int level, const char* str, int value); void print_par_stats(int level, const char* str, double* data); void print_par_sizes(int level, const char* str, double* data); void check_other_times(int level, NumberSeq* other_times_ms, NumberSeq* calc_other_times_ms) const; void print_summary (PauseSummary* stats) const; void print_summary (int level, const char* str, NumberSeq* seq) const; void print_summary_sd (int level, const char* str, NumberSeq* seq) const; double avg_value (double* data); double max_value (double* data); double sum_of_values (double* data); double max_sum (double* data1, double* data2); double _last_pause_time_ms; size_t _bytes_in_collection_set_before_gc; size_t _bytes_copied_during_gc; // Used to count used bytes in CS. friend class CountCSClosure; // 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. size_t _collection_set_bytes_used_before; // 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; // Used to record the highest end of heap region in collection set HeapWord* _inc_cset_max_finger; // The RSet lengths recorded for regions in the collection set // (updated by the periodic sampling of the regions in the // young list/collection set). size_t _inc_cset_recorded_rs_lengths; // The predicted elapsed time it will take to collect the regions // in the collection set (updated by the periodic sampling of the // regions in the young list/collection set). double _inc_cset_predicted_elapsed_time_ms; // Stash a pointer to the g1 heap. G1CollectedHeap* _g1; // The ratio of gc time to elapsed time, computed over recent pauses. double _recent_avg_pause_time_ratio; double recent_avg_pause_time_ratio() { return _recent_avg_pause_time_ratio; } // At the end of a pause we check the heap occupancy and we decide // whether we will start a marking cycle during the next pause. If // we decide that we want to do that, we will set this parameter to // true. So, this parameter will stay true between the end of a // pause and the beginning of a subsequent pause (not necessarily // the next one, see the comments on the next field) when we decide // that we will indeed start a marking cycle and do the initial-mark // work. volatile bool _initiate_conc_mark_if_possible; // If initiate_conc_mark_if_possible() is set at the beginning of a // pause, it is a suggestion that the pause should start a marking // cycle by doing the initial-mark work. However, it is possible // that the concurrent marking thread is still finishing up the // previous marking cycle (e.g., clearing the next marking // bitmap). If that is the case we cannot start a new cycle and // we'll have to wait for the concurrent marking thread to finish // what it is doing. In this case we will postpone the marking cycle // initiation decision for the next pause. When we eventually decide // to start a cycle, we will set _during_initial_mark_pause which // will stay true until the end of the initial-mark pause and it's // the condition that indicates that a pause is doing the // initial-mark work. volatile bool _during_initial_mark_pause; bool _should_revert_to_full_young_gcs; bool _last_full_young_gc; // This set of variables tracks the collector efficiency, in order to // determine whether we should initiate a new marking. double _cur_mark_stop_world_time_ms; double _mark_remark_start_sec; double _mark_cleanup_start_sec; double _mark_closure_time_ms; // 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. void update_young_list_target_length(size_t rs_lengths = (size_t) -1); // Calculate and return the minimum desired young list target // length. This is the minimum desired young list length according // to the user's inputs. size_t calculate_young_list_desired_min_length(size_t base_min_length); // Calculate and return the maximum desired young list target // length. This is the maximum desired young list length according // to the user's inputs. size_t calculate_young_list_desired_max_length(); // 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 alreay 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. size_t calculate_young_list_target_length(size_t rs_lengths, size_t base_min_length, size_t desired_min_length, size_t desired_max_length); // 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(size_t young_length, double base_time_ms, size_t base_free_regions, double target_pause_time_ms); // Count the number of bytes used in the CS. void count_CS_bytes_used(); void update_young_list_size_using_newratio(size_t number_of_heap_regions); public: G1CollectorPolicy(); virtual G1CollectorPolicy* as_g1_policy() { return this; } virtual CollectorPolicy::Name kind() { return CollectorPolicy::G1CollectorPolicyKind; } // 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 bytes_in_collection_set() { return _bytes_in_collection_set_before_gc; } unsigned calc_gc_alloc_time_stamp() { return _all_pause_times_ms->num() + 1; } // This should be called after the heap is resized. void record_new_heap_size(size_t new_number_of_regions); public: void init(); // Create jstat counters for the policy. virtual void initialize_gc_policy_counters(); virtual HeapWord* mem_allocate_work(size_t size, bool is_tlab, bool* gc_overhead_limit_was_exceeded); // This method controls how a collector handles one or more // of its generations being fully allocated. virtual HeapWord* satisfy_failed_allocation(size_t size, bool is_tlab); BarrierSet::Name barrier_set_name() { return BarrierSet::G1SATBCTLogging; } GenRemSet::Name rem_set_name() { return GenRemSet::CardTable; } // Update the heuristic info to record a collection pause of the given // start time, where the given number of bytes were used at the start. // This may involve changing the desired size of a collection set. void record_stop_world_start(); void record_collection_pause_start(double start_time_sec, size_t start_used); // Must currently be called while the world is stopped. void record_concurrent_mark_init_end(double mark_init_elapsed_time_ms); void record_mark_closure_time(double mark_closure_time_ms) { _mark_closure_time_ms = mark_closure_time_ms; } void record_concurrent_mark_remark_start(); void record_concurrent_mark_remark_end(); void record_concurrent_mark_cleanup_start(); void record_concurrent_mark_cleanup_end(int no_of_gc_threads); void record_concurrent_mark_cleanup_completed(); void record_concurrent_pause(); void record_concurrent_pause_end(); void record_collection_pause_end(int no_of_gc_threads); void print_heap_transition(); // Record the fact that a full collection occurred. void record_full_collection_start(); void record_full_collection_end(); void record_gc_worker_start_time(int worker_i, double ms) { _par_last_gc_worker_start_times_ms[worker_i] = ms; } void record_ext_root_scan_time(int worker_i, double ms) { _par_last_ext_root_scan_times_ms[worker_i] = ms; } void record_mark_stack_scan_time(int worker_i, double ms) { _par_last_mark_stack_scan_times_ms[worker_i] = ms; } void record_satb_drain_time(double ms) { assert(_g1->mark_in_progress(), "shouldn't be here otherwise"); _cur_satb_drain_time_ms = ms; } void record_update_rs_time(int thread, double ms) { _par_last_update_rs_times_ms[thread] = ms; } void record_update_rs_processed_buffers (int thread, double processed_buffers) { _par_last_update_rs_processed_buffers[thread] = processed_buffers; } void record_scan_rs_time(int thread, double ms) { _par_last_scan_rs_times_ms[thread] = ms; } void reset_obj_copy_time(int thread) { _par_last_obj_copy_times_ms[thread] = 0.0; } void reset_obj_copy_time() { reset_obj_copy_time(0); } void record_obj_copy_time(int thread, double ms) { _par_last_obj_copy_times_ms[thread] += ms; } void record_termination(int thread, double ms, size_t attempts) { _par_last_termination_times_ms[thread] = ms; _par_last_termination_attempts[thread] = (double) attempts; } void record_gc_worker_end_time(int worker_i, double ms) { _par_last_gc_worker_end_times_ms[worker_i] = ms; } void record_pause_time_ms(double ms) { _last_pause_time_ms = ms; } void record_clear_ct_time(double ms) { _cur_clear_ct_time_ms = ms; } void record_par_time(double ms) { _cur_collection_par_time_ms = ms; } void record_aux_start_time(int i) { guarantee(i < _aux_num, "should be within range"); _cur_aux_start_times_ms[i] = os::elapsedTime() * 1000.0; } void record_aux_end_time(int i) { guarantee(i < _aux_num, "should be within range"); double ms = os::elapsedTime() * 1000.0 - _cur_aux_start_times_ms[i]; _cur_aux_times_set[i] = true; _cur_aux_times_ms[i] += ms; } void record_ref_proc_time(double ms) { _cur_ref_proc_time_ms = ms; } void record_ref_enq_time(double ms) { _cur_ref_enq_time_ms = ms; } #ifndef PRODUCT void record_cc_clear_time(double ms) { if (_min_clear_cc_time_ms < 0.0 || ms <= _min_clear_cc_time_ms) _min_clear_cc_time_ms = ms; if (_max_clear_cc_time_ms < 0.0 || ms >= _max_clear_cc_time_ms) _max_clear_cc_time_ms = ms; _cur_clear_cc_time_ms = ms; _cum_clear_cc_time_ms += ms; _num_cc_clears++; } #endif // 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() { return _bytes_copied_during_gc; } // 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. void choose_collection_set(double target_pause_time_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(); 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/remove 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); void remove_from_incremental_cset_info(HeapRegion* hr); // 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); 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 bool initiate_conc_mark_if_possible() { return _initiate_conc_mark_if_possible; } void set_initiate_conc_mark_if_possible() { _initiate_conc_mark_if_possible = true; } void clear_initiate_conc_mark_if_possible() { _initiate_conc_mark_if_possible = false; } bool during_initial_mark_pause() { return _during_initial_mark_pause; } void set_during_initial_mark_pause() { _during_initial_mark_pause = true; } void clear_during_initial_mark_pause(){ _during_initial_mark_pause = false; } // 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. size_t expansion_amount(); #ifndef PRODUCT // Check any appropriate marked bytes info, asserting false if // something's wrong, else returning "true". bool assertMarkedBytesDataOK(); #endif // Print tracing information. void print_tracing_info() const; // 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 } bool is_young_list_full() { size_t young_list_length = _g1->young_list()->length(); size_t young_list_target_length = _young_list_target_length; return young_list_length >= young_list_target_length; } bool can_expand_young_list() { size_t young_list_length = _g1->young_list()->length(); size_t young_list_max_length = _young_list_max_length; return young_list_length < young_list_max_length; } size_t young_list_max_length() { return _young_list_max_length; } bool full_young_gcs() { return _full_young_gcs; } void set_full_young_gcs(bool full_young_gcs) { _full_young_gcs = full_young_gcs; } bool adaptive_young_list_length() { return _adaptive_young_list_length; } void set_adaptive_young_list_length(bool adaptive_young_list_length) { _adaptive_young_list_length = adaptive_young_list_length; } inline double get_gc_eff_factor() { double ratio = _known_garbage_ratio; double square = ratio * ratio; // square = square * square; double ret = square * 9.0 + 1.0; #if 0 gclog_or_tty->print_cr("ratio = %1.2lf, ret = %1.2lf", ratio, ret); #endif // 0 guarantee(0.0 <= ret && ret < 10.0, "invariant!"); return ret; } private: // // Survivor regions policy. // // Current tenuring threshold, set to 0 if the collector reaches the // maximum amount of suvivors regions. int _tenuring_threshold; // The limit on the number of regions allocated for survivors. size_t _max_survivor_regions; // For reporting purposes. size_t _eden_bytes_before_gc; size_t _survivor_bytes_before_gc; size_t _capacity_before_gc; // The amount of survor regions after a collection. size_t _recorded_survivor_regions; // List of survivor regions. HeapRegion* _recorded_survivor_head; HeapRegion* _recorded_survivor_tail; ageTable _survivors_age_table; public: inline GCAllocPurpose evacuation_destination(HeapRegion* src_region, int age, size_t word_sz) { if (age < _tenuring_threshold && src_region->is_young()) { return GCAllocForSurvived; } else { return GCAllocForTenured; } } inline bool track_object_age(GCAllocPurpose purpose) { return purpose == GCAllocForSurvived; } static const size_t REGIONS_UNLIMITED = ~(size_t)0; size_t max_regions(int purpose); // The limit on regions for a particular purpose is reached. void note_alloc_region_limit_reached(int purpose) { if (purpose == GCAllocForSurvived) { _tenuring_threshold = 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(size_t regions, HeapRegion* head, HeapRegion* tail) { _recorded_survivor_regions = regions; _recorded_survivor_head = head; _recorded_survivor_tail = tail; } size_t recorded_survivor_regions() { return _recorded_survivor_regions; } void record_thread_age_table(ageTable* age_table) { _survivors_age_table.merge_par(age_table); } void update_max_gc_locker_expansion(); // Calculates survivor space parameters. void update_survivors_policy(); }; // This should move to some place more general... // If we have "n" measurements, and we've kept track of their "sum" and the // "sum_of_squares" of the measurements, this returns the variance of the // sequence. inline double variance(int n, double sum_of_squares, double sum) { double n_d = (double)n; double avg = sum/n_d; return (sum_of_squares - 2.0 * avg * sum + n_d * avg * avg) / n_d; } #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTORPOLICY_HPP