src/hotspot/share/gc/g1/g1Analytics.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_GC_G1_G1ANALYTICS_HPP
#define SHARE_GC_G1_G1ANALYTICS_HPP

#include "memory/allocation.hpp"
#include "utilities/globalDefinitions.hpp"

class TruncatedSeq;
class G1Predictions;

class G1Analytics: public CHeapObj<mtGC> {
  const static int TruncatedSeqLength = 10;
  const static int NumPrevPausesForHeuristics = 10;
  const G1Predictions* _predictor;

  // These exclude marking times.
  TruncatedSeq* _recent_gc_times_ms;

  TruncatedSeq* _concurrent_mark_remark_times_ms;
  TruncatedSeq* _concurrent_mark_cleanup_times_ms;

  TruncatedSeq* _alloc_rate_ms_seq;
  double        _prev_collection_pause_end_ms;

  TruncatedSeq* _rs_length_diff_seq;
  TruncatedSeq* _concurrent_refine_rate_ms_seq;
  TruncatedSeq* _logged_cards_rate_ms_seq;
  TruncatedSeq* _cost_per_logged_card_ms_seq;
  TruncatedSeq* _cost_scan_hcc_seq;
  TruncatedSeq* _young_cards_per_entry_ratio_seq;
  TruncatedSeq* _mixed_cards_per_entry_ratio_seq;
  TruncatedSeq* _young_only_cost_per_remset_card_ms_seq;
  TruncatedSeq* _mixed_cost_per_remset_card_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_length_seq;

  TruncatedSeq* _cost_per_byte_ms_during_cm_seq;

  // Statistics kept per GC stoppage, pause or full.
  TruncatedSeq* _recent_prev_end_times_for_all_gcs_sec;

  // 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 get_new_prediction(TruncatedSeq const* seq) const;
  size_t get_new_size_prediction(TruncatedSeq const* seq) const;

public:
  G1Analytics(const G1Predictions* predictor);

  double prev_collection_pause_end_ms() const {
    return _prev_collection_pause_end_ms;
  }

  double recent_avg_pause_time_ratio() const {
    return _recent_avg_pause_time_ratio;
  }

  double last_pause_time_ratio() const {
    return _last_pause_time_ratio;
  }

  uint number_of_recorded_pause_times() const {
    return NumPrevPausesForHeuristics;
  }

  void append_prev_collection_pause_end_ms(double ms) {
    _prev_collection_pause_end_ms += ms;
  }

  void report_concurrent_mark_remark_times_ms(double ms);
  void report_concurrent_mark_cleanup_times_ms(double ms);
  void report_alloc_rate_ms(double alloc_rate);
  void report_concurrent_refine_rate_ms(double cards_per_ms);
  void report_logged_cards_rate_ms(double cards_per_ms);
  void report_cost_per_logged_card_ms(double cost_per_logged_card_ms);
  void report_cost_scan_hcc(double cost_scan_hcc);
  void report_cost_per_remset_card_ms(double cost_per_remset_card_ms, bool for_young_gc);
  void report_cards_per_entry_ratio(double cards_per_entry_ratio, bool for_young_gc);
  void report_rs_length_diff(double rs_length_diff);
  void report_cost_per_byte_ms(double cost_per_byte_ms, bool mark_or_rebuild_in_progress);
  void report_young_other_cost_per_region_ms(double other_cost_per_region_ms);
  void report_non_young_other_cost_per_region_ms(double other_cost_per_region_ms);
  void report_constant_other_time_ms(double constant_other_time_ms);
  void report_pending_cards(double pending_cards);
  void report_rs_length(double rs_length);

  double predict_alloc_rate_ms() const;
  int num_alloc_rate_ms() const;

  double predict_concurrent_refine_rate_ms() const;
  double predict_logged_cards_rate_ms() const;
  double predict_cost_per_logged_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_card_num(size_t rs_length, bool for_young_gc) const;

  double predict_rs_scan_time_ms(size_t card_num, bool for_young_gc) 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, bool during_concurrent_mark) 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_remark_time_ms() const;

  double predict_cleanup_time_ms() const;

  size_t predict_rs_length() const;
  size_t predict_pending_cards() const;

  double predict_cost_per_byte_ms() const;

  // 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);
  void compute_pause_time_ratio(double interval_ms, double pause_time_ms);

  double last_known_gc_end_time_sec() const;
};

#endif // SHARE_GC_G1_G1ANALYTICS_HPP