0N/A

1879N/A#ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSADAPTIVESIZEPOLICY_HPP

1879N/A#define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSADAPTIVESIZEPOLICY_HPP

1879N/A

1879N/A#include "gc_implementation/shared/adaptiveSizePolicy.hpp"

1879N/A#include "gc_implementation/shared/gcStats.hpp"

1879N/A#include "gc_implementation/shared/gcUtil.hpp"

1879N/A#include "gc_interface/gcCause.hpp"

1879N/A

0N/A

0N/Aclass elapsedTimer;

1387N/Aclass GenerationSizer;

0N/A

0N/Aclass PSAdaptiveSizePolicy : public AdaptiveSizePolicy {

0N/A friend class PSGCAdaptivePolicyCounters;

0N/A private:

0N/A // These values are used to record decisions made during the

0N/A // policy. For example, if the young generation was decreased

0N/A // to decrease the GC cost of minor collections the value

0N/A // decrease_young_gen_for_throughput_true is used.

0N/A

0N/A // Last calculated sizes, in bytes, and aligned

0N/A // NEEDS_CLEANUP should use sizes.hpp, but it works in ints, not size_t's

0N/A

0N/A // Time statistics

0N/A AdaptivePaddedAverage* _avg_major_pause;

0N/A

0N/A // Footprint statistics

0N/A AdaptiveWeightedAverage* _avg_base_footprint;

0N/A

0N/A // Statistical data gathered for GC

0N/A GCStats _gc_stats;

0N/A

0N/A size_t _survivor_size_limit; // Limit in bytes of survivor size

0N/A const double _collection_cost_margin_fraction;

0N/A

0N/A // Variable for estimating the major and minor pause times.

0N/A // These variables represent linear least-squares fits of

0N/A // the data.

0N/A // major pause time vs. old gen size

0N/A LinearLeastSquareFit* _major_pause_old_estimator;

0N/A // major pause time vs. young gen size

0N/A LinearLeastSquareFit* _major_pause_young_estimator;

0N/A

0N/A

0N/A // These record the most recent collection times. They

0N/A // are available as an alternative to using the averages

0N/A // for making ergonomic decisions.

0N/A double _latest_major_mutator_interval_seconds;

0N/A

0N/A const size_t _intra_generation_alignment; // alignment for eden, survivors

0N/A

0N/A const double _gc_minor_pause_goal_sec; // goal for maximum minor gc pause

0N/A

0N/A // The amount of live data in the heap at the last full GC, used

0N/A // as a baseline to help us determine when we need to perform the

0N/A // next full GC.

0N/A size_t _live_at_last_full_gc;

0N/A

0N/A // decrease/increase the old generation for minor pause time

0N/A int _change_old_gen_for_min_pauses;

0N/A

0N/A // increase/decrease the young generation for major pause time

0N/A int _change_young_gen_for_maj_pauses;

0N/A

0N/A

0N/A // Flag indicating that the adaptive policy is ready to use

0N/A bool _old_gen_policy_is_ready;

0N/A

0N/A // Changing the generation sizing depends on the data that is

0N/A // gathered about the effects of changes on the pause times and

0N/A // throughput. These variable count the number of data points

0N/A // gathered. The policy may use these counters as a threshhold

0N/A // for reliable data.

0N/A julong _young_gen_change_for_major_pause_count;

0N/A

0N/A // To facilitate faster growth at start up, supplement the normal

0N/A // growth percentage for the young gen eden and the

0N/A // old gen space for promotion with these value which decay

0N/A // with increasing collections.

0N/A uint _young_gen_size_increment_supplement;

0N/A uint _old_gen_size_increment_supplement;

0N/A

0N/A // The number of bytes absorbed from eden into the old gen by moving the

0N/A // boundary over live data.

0N/A size_t _bytes_absorbed_from_eden;

0N/A

0N/A private:

0N/A

0N/A // Accessors

0N/A AdaptivePaddedAverage* avg_major_pause() const { return _avg_major_pause; }

0N/A double gc_minor_pause_goal_sec() const { return _gc_minor_pause_goal_sec; }

0N/A

0N/A // Change the young generation size to achieve a minor GC pause time goal

0N/A void adjust_for_minor_pause_time(bool is_full_gc,

0N/A size_t* desired_promo_size_ptr,

0N/A size_t* desired_eden_size_ptr);

0N/A // Change the generation sizes to achieve a GC pause time goal

0N/A // Returned sizes are not necessarily aligned.

0N/A void adjust_for_pause_time(bool is_full_gc,

0N/A size_t* desired_promo_size_ptr,

0N/A size_t* desired_eden_size_ptr);

0N/A // Change the generation sizes to achieve an application throughput goal

0N/A // Returned sizes are not necessarily aligned.

0N/A void adjust_for_throughput(bool is_full_gc,

0N/A size_t* desired_promo_size_ptr,

0N/A size_t* desired_eden_size_ptr);

0N/A // Change the generation sizes to achieve minimum footprint

0N/A // Returned sizes are not aligned.

0N/A size_t adjust_promo_for_footprint(size_t desired_promo_size,

0N/A size_t desired_total);

0N/A size_t adjust_eden_for_footprint(size_t desired_promo_size,

0N/A size_t desired_total);

0N/A

0N/A // Size in bytes for an increment or decrement of eden.

0N/A virtual size_t eden_increment(size_t cur_eden, uint percent_change);

0N/A virtual size_t eden_decrement(size_t cur_eden);

0N/A size_t eden_decrement_aligned_down(size_t cur_eden);

0N/A size_t eden_increment_with_supplement_aligned_up(size_t cur_eden);

0N/A

0N/A // Size in bytes for an increment or decrement of the promotion area

0N/A virtual size_t promo_increment(size_t cur_promo, uint percent_change);

0N/A virtual size_t promo_decrement(size_t cur_promo);

0N/A size_t promo_decrement_aligned_down(size_t cur_promo);

0N/A size_t promo_increment_with_supplement_aligned_up(size_t cur_promo);

0N/A

0N/A // Decay the supplemental growth additive.

0N/A void decay_supplemental_growth(bool is_full_gc);

0N/A

0N/A // Returns a change that has been scaled down. Result

0N/A // is not aligned. (If useful, move to some shared

0N/A // location.)

0N/A size_t scale_down(size_t change, double part, double total);

0N/A

0N/A protected:

0N/A // Time accessors

0N/A

0N/A // Footprint accessors

0N/A size_t live_space() const {

0N/A return (size_t)(avg_base_footprint()->average() +

0N/A avg_young_live()->average() +

0N/A avg_old_live()->average());

0N/A }

0N/A size_t free_space() const {

0N/A return _eden_size + _promo_size;

0N/A }

0N/A

0N/A void set_promo_size(size_t new_size) {

0N/A _promo_size = new_size;

0N/A }

0N/A void set_survivor_size(size_t new_size) {

0N/A _survivor_size = new_size;

0N/A }

0N/A

0N/A // Update estimators

0N/A void update_minor_pause_old_estimator(double minor_pause_in_ms);

0N/A

0N/A virtual GCPolicyKind kind() const { return _gc_ps_adaptive_size_policy; }

0N/A

0N/A public:

0N/A // Use by ASPSYoungGen and ASPSOldGen to limit boundary moving.

0N/A size_t eden_increment_aligned_up(size_t cur_eden);

0N/A size_t eden_increment_aligned_down(size_t cur_eden);

0N/A size_t promo_increment_aligned_up(size_t cur_promo);

0N/A size_t promo_increment_aligned_down(size_t cur_promo);

0N/A

0N/A virtual size_t eden_increment(size_t cur_eden);

0N/A virtual size_t promo_increment(size_t cur_promo);

0N/A

0N/A // Accessors for use by performance counters

0N/A AdaptivePaddedNoZeroDevAverage* avg_promoted() const {

0N/A return _gc_stats.avg_promoted();

0N/A }

0N/A AdaptiveWeightedAverage* avg_base_footprint() const {

0N/A return _avg_base_footprint;

0N/A }

0N/A

0N/A // Input arguments are initial free space sizes for young and old

0N/A // generations, the initial survivor space size, the

0N/A // alignment values and the pause & throughput goals.

0N/A //

0N/A // NEEDS_CLEANUP this is a singleton object

0N/A PSAdaptiveSizePolicy(size_t init_eden_size,

0N/A size_t init_promo_size,

0N/A size_t init_survivor_size,

0N/A size_t intra_generation_alignment,

0N/A double gc_pause_goal_sec,

0N/A double gc_minor_pause_goal_sec,

0N/A uint gc_time_ratio);

0N/A

0N/A // Methods indicating events of interest to the adaptive size policy,

0N/A // called by GC algorithms. It is the responsibility of users of this

0N/A // policy to call these methods at the correct times!

0N/A void major_collection_begin();

0N/A void major_collection_end(size_t amount_live, GCCause::Cause gc_cause);

0N/A

0N/A //

0N/A void tenured_allocation(size_t size) {

0N/A _avg_pretenured->sample(size);

0N/A }

0N/A

0N/A // Accessors

0N/A // NEEDS_CLEANUP should use sizes.hpp

0N/A

0N/A size_t calculated_old_free_size_in_bytes() const {

0N/A return (size_t)(_promo_size + avg_promoted()->padded_average());

0N/A }

0N/A

0N/A size_t average_old_live_in_bytes() const {

0N/A return (size_t) avg_old_live()->average();

0N/A }

0N/A

0N/A size_t average_promoted_in_bytes() const {

0N/A return (size_t)avg_promoted()->average();

0N/A }

0N/A

0N/A size_t padded_average_promoted_in_bytes() const {

0N/A return (size_t)avg_promoted()->padded_average();

0N/A }

0N/A

0N/A int change_young_gen_for_maj_pauses() {

0N/A return _change_young_gen_for_maj_pauses;

0N/A }

0N/A void set_change_young_gen_for_maj_pauses(int v) {

0N/A _change_young_gen_for_maj_pauses = v;

0N/A }

0N/A

0N/A int change_old_gen_for_min_pauses() {

0N/A return _change_old_gen_for_min_pauses;

0N/A }

0N/A void set_change_old_gen_for_min_pauses(int v) {

0N/A _change_old_gen_for_min_pauses = v;

0N/A }

0N/A

0N/A // Return true if the old generation size was changed

0N/A // to try to reach a pause time goal.

0N/A bool old_gen_changed_for_pauses() {

0N/A bool result = _change_old_gen_for_maj_pauses != 0 ||

0N/A _change_old_gen_for_min_pauses != 0;

0N/A return result;

0N/A }

0N/A

0N/A // Return true if the young generation size was changed

0N/A // to try to reach a pause time goal.

0N/A bool young_gen_changed_for_pauses() {

0N/A bool result = _change_young_gen_for_min_pauses != 0 ||

0N/A _change_young_gen_for_maj_pauses != 0;

0N/A return result;

0N/A }

0N/A // end flags for pause goal

0N/A

0N/A // Return true if the old generation size was changed

0N/A // to try to reach a throughput goal.

0N/A bool old_gen_changed_for_throughput() {

0N/A bool result = _change_old_gen_for_throughput != 0;

0N/A return result;

0N/A }

0N/A

0N/A // Return true if the young generation size was changed

0N/A // to try to reach a throughput goal.

0N/A bool young_gen_changed_for_throughput() {

0N/A bool result = _change_young_gen_for_throughput != 0;

0N/A return result;

0N/A }

0N/A

0N/A int decrease_for_footprint() { return _decrease_for_footprint; }

0N/A

0N/A

0N/A // Accessors for estimators. The slope of the linear fit is

0N/A // currently all that is used for making decisions.

0N/A

0N/A LinearLeastSquareFit* major_pause_old_estimator() {

0N/A return _major_pause_old_estimator;

0N/A }

0N/A

0N/A LinearLeastSquareFit* major_pause_young_estimator() {

0N/A return _major_pause_young_estimator;

0N/A }

0N/A

0N/A

0N/A virtual void clear_generation_free_space_flags();

0N/A

0N/A float major_pause_old_slope() { return _major_pause_old_estimator->slope(); }

0N/A float major_pause_young_slope() {

0N/A return _major_pause_young_estimator->slope();

0N/A }

0N/A float major_collection_slope() { return _major_collection_estimator->slope();}

0N/A

0N/A bool old_gen_policy_is_ready() { return _old_gen_policy_is_ready; }

0N/A

0N/A // Given the amount of live data in the heap, should we

0N/A // perform a Full GC?

0N/A bool should_full_GC(size_t live_in_old_gen);

0N/A

0N/A // Calculates optimial free space sizes for both the old and young

0N/A // generations. Stores results in _eden_size and _promo_size.

0N/A // Takes current used space in all generations as input, as well

0N/A // as an indication if a full gc has just been performed, for use

0N/A // in deciding if an OOM error should be thrown.

0N/A void compute_generation_free_space(size_t young_live,

0N/A size_t eden_live,

0N/A size_t old_live,

0N/A size_t perm_live,

0N/A size_t cur_eden, // current eden in bytes

0N/A size_t max_old_gen_size,

0N/A size_t max_eden_size,

0N/A bool is_full_gc,

1387N/A GCCause::Cause gc_cause,

1387N/A CollectorPolicy* collector_policy);

0N/A

0N/A // Calculates new survivor space size; returns a new tenuring threshold

0N/A // value. Stores new survivor size in _survivor_size.

0N/A int compute_survivor_space_size_and_threshold(bool is_survivor_overflow,

0N/A int tenuring_threshold,

0N/A size_t survivor_limit);

0N/A

0N/A // Return the maximum size of a survivor space if the young generation were of

0N/A // size gen_size.

0N/A size_t max_survivor_size(size_t gen_size) {

0N/A // Never allow the target survivor size to grow more than MinSurvivorRatio

0N/A // of the young generation size. We cannot grow into a two semi-space

0N/A // system, with Eden zero sized. Even if the survivor space grows, from()

0N/A // might grow by moving the bottom boundary "down" -- so from space will

0N/A // remain almost full anyway (top() will be near end(), but there will be a

0N/A // large filler object at the bottom).

0N/A const size_t sz = gen_size / MinSurvivorRatio;

0N/A const size_t alignment = _intra_generation_alignment;

0N/A return sz > alignment ? align_size_down(sz, alignment) : alignment;

0N/A }

0N/A

0N/A size_t live_at_last_full_gc() {

0N/A return _live_at_last_full_gc;

0N/A }

0N/A

0N/A size_t bytes_absorbed_from_eden() const { return _bytes_absorbed_from_eden; }

0N/A void reset_bytes_absorbed_from_eden() { _bytes_absorbed_from_eden = 0; }

0N/A

0N/A void set_bytes_absorbed_from_eden(size_t val) {

0N/A _bytes_absorbed_from_eden = val;

0N/A }

0N/A

0N/A // Update averages that are always used (even

0N/A // if adaptive sizing is turned off).

0N/A void update_averages(bool is_survivor_overflow,

0N/A size_t survived,

0N/A size_t promoted);

0N/A

0N/A // Printing support

0N/A virtual bool print_adaptive_size_policy_on(outputStream* st) const;

0N/A};

1879N/A

1879N/A#endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSADAPTIVESIZEPOLICY_HPP