--- a/hotspot/src/share/vm/gc/g1/g1CollectorPolicy.hpp Mon Apr 18 22:40:47 2016 +0200
+++ b/hotspot/src/share/vm/gc/g1/g1CollectorPolicy.hpp Fri Mar 18 15:20:43 2016 +0100
@@ -25,419 +25,27 @@
#ifndef SHARE_VM_GC_G1_G1COLLECTORPOLICY_HPP
#define SHARE_VM_GC_G1_G1COLLECTORPOLICY_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.
+// G1CollectorPolicy is primarily used during initialization and to expose the
+// functionality of the CollectorPolicy interface to the rest of the VM.
-class HeapRegion;
-class G1CollectionSet;
-class CollectionSetChooser;
-class G1IHOPControl;
-class G1Analytics;
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;
- G1Analytics* _analytics;
- G1MMUTracker* _mmu_tracker;
-
+protected:
void initialize_alignments();
void initialize_flags();
- double _full_collection_start_sec;
-
- 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;
-
- double _reserve_factor;
- uint _reserve_regions;
-
- G1YoungGenSizer* _young_gen_sizer;
-
- uint _free_regions_at_end_of_collection;
-
- size_t _max_rs_lengths;
-
- size_t _rs_lengths_prediction;
-
-#ifndef PRODUCT
- bool verify_young_ages(HeapRegion* head, SurvRateGroup *surv_rate_group);
-#endif // PRODUCT
-
- 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; }
- const G1Analytics* analytics() const { return const_cast<const G1Analytics*>(_analytics); }
-
- // 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;
- }
-
-
- 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;
-
- 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;
- }
-
- // 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:
- G1CollectionSet* _collection_set;
- 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;
-private:
-
- // The number of bytes copied during the GC.
- size_t _bytes_copied_during_gc;
-
- // Stash a pointer to the g1 heap.
- G1CollectedHeap* _g1;
-
- G1GCPhaseTimes* _phase_times;
-
- // 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);
-
- // 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;
-
-public:
- size_t pending_cards() const { return _pending_cards; }
-
- // 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;
-
-private:
- // 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; }
+ G1CollectorPolicy* as_g1_policy() { return this; }
- // 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();
+ void post_heap_initialize() {} // Nothing needed.
// 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;
- }
-
- // 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;
-
- virtual void finalize_collection_set(double target_pause_time_ms);
-private:
- // 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:
- // 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();
-
- // 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();
- }
- }
-
- 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;
-
- AgeTable _survivors_age_table;
-
-public:
- uint tenuring_threshold() const { return _tenuring_threshold; }
-
- uint max_survivor_regions() {
- return _max_survivor_regions;
- }
-
- 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_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