| /* |
| * Copyright (c) 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. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "gc/g1/g1Analytics.hpp" |
| #include "gc/g1/g1Predictions.hpp" |
| #include "runtime/os.hpp" |
| #include "utilities/debug.hpp" |
| #include "utilities/numberSeq.hpp" |
| |
| // Different defaults for different number of GC threads |
| // They were chosen by running GCOld and SPECjbb on debris with different |
| // numbers of GC threads and choosing them based on the results |
| |
| // all the same |
| static double rs_length_diff_defaults[] = { |
| 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 |
| }; |
| |
| static double cost_per_card_ms_defaults[] = { |
| 0.01, 0.005, 0.005, 0.003, 0.003, 0.002, 0.002, 0.0015 |
| }; |
| |
| // all the same |
| static double young_cards_per_entry_ratio_defaults[] = { |
| 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0 |
| }; |
| |
| static double cost_per_entry_ms_defaults[] = { |
| 0.015, 0.01, 0.01, 0.008, 0.008, 0.0055, 0.0055, 0.005 |
| }; |
| |
| static double cost_per_byte_ms_defaults[] = { |
| 0.00006, 0.00003, 0.00003, 0.000015, 0.000015, 0.00001, 0.00001, 0.000009 |
| }; |
| |
| // these should be pretty consistent |
| static double constant_other_time_ms_defaults[] = { |
| 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0 |
| }; |
| |
| |
| static double young_other_cost_per_region_ms_defaults[] = { |
| 0.3, 0.2, 0.2, 0.15, 0.15, 0.12, 0.12, 0.1 |
| }; |
| |
| static double non_young_other_cost_per_region_ms_defaults[] = { |
| 1.0, 0.7, 0.7, 0.5, 0.5, 0.42, 0.42, 0.30 |
| }; |
| |
| G1Analytics::G1Analytics(const G1Predictions* predictor) : |
| _predictor(predictor), |
| _recent_gc_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)), |
| _concurrent_mark_remark_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)), |
| _concurrent_mark_cleanup_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)), |
| _alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _prev_collection_pause_end_ms(0.0), |
| _rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _cost_scan_hcc_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _young_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _mixed_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _mixed_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _cost_per_byte_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _cost_per_byte_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _constant_other_time_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _non_young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _pending_cards_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _rs_lengths_seq(new TruncatedSeq(TruncatedSeqLength)), |
| _recent_prev_end_times_for_all_gcs_sec(new TruncatedSeq(NumPrevPausesForHeuristics)) { |
| |
| // Seed sequences with initial values. |
| _recent_prev_end_times_for_all_gcs_sec->add(os::elapsedTime()); |
| _prev_collection_pause_end_ms = os::elapsedTime() * 1000.0; |
| |
| int index = MIN2(ParallelGCThreads - 1, 7u); |
| |
| _rs_length_diff_seq->add(rs_length_diff_defaults[index]); |
| _cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]); |
| _cost_scan_hcc_seq->add(0.0); |
| _young_cards_per_entry_ratio_seq->add(young_cards_per_entry_ratio_defaults[index]); |
| _cost_per_entry_ms_seq->add(cost_per_entry_ms_defaults[index]); |
| _cost_per_byte_ms_seq->add(cost_per_byte_ms_defaults[index]); |
| _constant_other_time_ms_seq->add(constant_other_time_ms_defaults[index]); |
| _young_other_cost_per_region_ms_seq->add(young_other_cost_per_region_ms_defaults[index]); |
| _non_young_other_cost_per_region_ms_seq->add(non_young_other_cost_per_region_ms_defaults[index]); |
| |
| // start conservatively (around 50ms is about right) |
| _concurrent_mark_remark_times_ms->add(0.05); |
| _concurrent_mark_cleanup_times_ms->add(0.20); |
| } |
| |
| double G1Analytics::get_new_prediction(TruncatedSeq const* seq) const { |
| return _predictor->get_new_prediction(seq); |
| } |
| |
| size_t G1Analytics::get_new_size_prediction(TruncatedSeq const* seq) const { |
| return (size_t)get_new_prediction(seq); |
| } |
| |
| int G1Analytics::num_alloc_rate_ms() const { |
| return _alloc_rate_ms_seq->num(); |
| } |
| |
| void G1Analytics::report_concurrent_mark_remark_times_ms(double ms) { |
| _concurrent_mark_remark_times_ms->add(ms); |
| } |
| |
| void G1Analytics::report_alloc_rate_ms(double alloc_rate) { |
| _alloc_rate_ms_seq->add(alloc_rate); |
| } |
| |
| void G1Analytics::compute_pause_time_ratio(double interval_ms, double pause_time_ms) { |
| _recent_avg_pause_time_ratio = _recent_gc_times_ms->sum() / interval_ms; |
| if (_recent_avg_pause_time_ratio < 0.0 || |
| (_recent_avg_pause_time_ratio - 1.0 > 0.0)) { |
| // Clip ratio between 0.0 and 1.0, and continue. This will be fixed in |
| // CR 6902692 by redoing the manner in which the ratio is incrementally computed. |
| if (_recent_avg_pause_time_ratio < 0.0) { |
| _recent_avg_pause_time_ratio = 0.0; |
| } else { |
| assert(_recent_avg_pause_time_ratio - 1.0 > 0.0, "Ctl-point invariant"); |
| _recent_avg_pause_time_ratio = 1.0; |
| } |
| } |
| |
| // Compute the ratio of just this last pause time to the entire time range stored |
| // in the vectors. Comparing this pause to the entire range, rather than only the |
| // most recent interval, has the effect of smoothing over a possible transient 'burst' |
| // of more frequent pauses that don't really reflect a change in heap occupancy. |
| // This reduces the likelihood of a needless heap expansion being triggered. |
| _last_pause_time_ratio = |
| (pause_time_ms * _recent_prev_end_times_for_all_gcs_sec->num()) / interval_ms; |
| } |
| |
| void G1Analytics::report_cost_per_card_ms(double cost_per_card_ms) { |
| _cost_per_card_ms_seq->add(cost_per_card_ms); |
| } |
| |
| void G1Analytics::report_cost_scan_hcc(double cost_scan_hcc) { |
| _cost_scan_hcc_seq->add(cost_scan_hcc); |
| } |
| |
| void G1Analytics::report_cost_per_entry_ms(double cost_per_entry_ms, bool last_gc_was_young) { |
| if (last_gc_was_young) { |
| _cost_per_entry_ms_seq->add(cost_per_entry_ms); |
| } else { |
| _mixed_cost_per_entry_ms_seq->add(cost_per_entry_ms); |
| } |
| } |
| |
| void G1Analytics::report_cards_per_entry_ratio(double cards_per_entry_ratio, bool last_gc_was_young) { |
| if (last_gc_was_young) { |
| _young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio); |
| } else { |
| _mixed_cards_per_entry_ratio_seq->add(cards_per_entry_ratio); |
| } |
| } |
| |
| void G1Analytics::report_rs_length_diff(double rs_length_diff) { |
| _rs_length_diff_seq->add(rs_length_diff); |
| } |
| |
| void G1Analytics::report_cost_per_byte_ms(double cost_per_byte_ms, bool in_marking_window) { |
| if (in_marking_window) { |
| _cost_per_byte_ms_during_cm_seq->add(cost_per_byte_ms); |
| } else { |
| _cost_per_byte_ms_seq->add(cost_per_byte_ms); |
| } |
| } |
| |
| void G1Analytics::report_young_other_cost_per_region_ms(double other_cost_per_region_ms) { |
| _young_other_cost_per_region_ms_seq->add(other_cost_per_region_ms); |
| } |
| |
| void G1Analytics::report_non_young_other_cost_per_region_ms(double other_cost_per_region_ms) { |
| _non_young_other_cost_per_region_ms_seq->add(other_cost_per_region_ms); |
| } |
| |
| void G1Analytics::report_constant_other_time_ms(double constant_other_time_ms) { |
| _constant_other_time_ms_seq->add(constant_other_time_ms); |
| } |
| |
| void G1Analytics::report_pending_cards(double pending_cards) { |
| _pending_cards_seq->add(pending_cards); |
| } |
| |
| void G1Analytics::report_rs_lengths(double rs_lengths) { |
| _rs_lengths_seq->add(rs_lengths); |
| } |
| |
| size_t G1Analytics::predict_rs_length_diff() const { |
| return get_new_size_prediction(_rs_length_diff_seq); |
| } |
| |
| double G1Analytics::predict_alloc_rate_ms() const { |
| return get_new_prediction(_alloc_rate_ms_seq); |
| } |
| |
| double G1Analytics::predict_cost_per_card_ms() const { |
| return get_new_prediction(_cost_per_card_ms_seq); |
| } |
| |
| double G1Analytics::predict_scan_hcc_ms() const { |
| return get_new_prediction(_cost_scan_hcc_seq); |
| } |
| |
| double G1Analytics::predict_rs_update_time_ms(size_t pending_cards) const { |
| return pending_cards * predict_cost_per_card_ms() + predict_scan_hcc_ms(); |
| } |
| |
| double G1Analytics::predict_young_cards_per_entry_ratio() const { |
| return get_new_prediction(_young_cards_per_entry_ratio_seq); |
| } |
| |
| double G1Analytics::predict_mixed_cards_per_entry_ratio() const { |
| if (_mixed_cards_per_entry_ratio_seq->num() < 2) { |
| return predict_young_cards_per_entry_ratio(); |
| } else { |
| return get_new_prediction(_mixed_cards_per_entry_ratio_seq); |
| } |
| } |
| |
| size_t G1Analytics::predict_card_num(size_t rs_length, bool gcs_are_young) const { |
| if (gcs_are_young) { |
| return (size_t) (rs_length * predict_young_cards_per_entry_ratio()); |
| } else { |
| return (size_t) (rs_length * predict_mixed_cards_per_entry_ratio()); |
| } |
| } |
| |
| double G1Analytics::predict_rs_scan_time_ms(size_t card_num, bool gcs_are_young) const { |
| if (gcs_are_young) { |
| return card_num * get_new_prediction(_cost_per_entry_ms_seq); |
| } else { |
| return predict_mixed_rs_scan_time_ms(card_num); |
| } |
| } |
| |
| double G1Analytics::predict_mixed_rs_scan_time_ms(size_t card_num) const { |
| if (_mixed_cost_per_entry_ms_seq->num() < 3) { |
| return card_num * get_new_prediction(_cost_per_entry_ms_seq); |
| } else { |
| return card_num * get_new_prediction(_mixed_cost_per_entry_ms_seq); |
| } |
| } |
| |
| double G1Analytics::predict_object_copy_time_ms_during_cm(size_t bytes_to_copy) const { |
| if (_cost_per_byte_ms_during_cm_seq->num() < 3) { |
| return (1.1 * bytes_to_copy) * get_new_prediction(_cost_per_byte_ms_seq); |
| } else { |
| return bytes_to_copy * get_new_prediction(_cost_per_byte_ms_during_cm_seq); |
| } |
| } |
| |
| double G1Analytics::predict_object_copy_time_ms(size_t bytes_to_copy, bool during_concurrent_mark) const { |
| if (during_concurrent_mark) { |
| return predict_object_copy_time_ms_during_cm(bytes_to_copy); |
| } else { |
| return bytes_to_copy * get_new_prediction(_cost_per_byte_ms_seq); |
| } |
| } |
| |
| double G1Analytics::predict_constant_other_time_ms() const { |
| return get_new_prediction(_constant_other_time_ms_seq); |
| } |
| |
| double G1Analytics::predict_young_other_time_ms(size_t young_num) const { |
| return young_num * get_new_prediction(_young_other_cost_per_region_ms_seq); |
| } |
| |
| double G1Analytics::predict_non_young_other_time_ms(size_t non_young_num) const { |
| return non_young_num * get_new_prediction(_non_young_other_cost_per_region_ms_seq); |
| } |
| |
| double G1Analytics::predict_remark_time_ms() const { |
| return get_new_prediction(_concurrent_mark_remark_times_ms); |
| } |
| |
| double G1Analytics::predict_cleanup_time_ms() const { |
| return get_new_prediction(_concurrent_mark_cleanup_times_ms); |
| } |
| |
| size_t G1Analytics::predict_rs_lengths() const { |
| return get_new_size_prediction(_rs_lengths_seq); |
| } |
| |
| size_t G1Analytics::predict_pending_cards() const { |
| return get_new_size_prediction(_pending_cards_seq); |
| } |
| |
| double G1Analytics::last_known_gc_end_time_sec() const { |
| return _recent_prev_end_times_for_all_gcs_sec->oldest(); |
| } |
| |
| void G1Analytics::update_recent_gc_times(double end_time_sec, |
| double pause_time_ms) { |
| _recent_gc_times_ms->add(pause_time_ms); |
| _recent_prev_end_times_for_all_gcs_sec->add(end_time_sec); |
| _prev_collection_pause_end_ms = end_time_sec * 1000.0; |
| } |
| |
| void G1Analytics::report_concurrent_mark_cleanup_times_ms(double ms) { |
| _concurrent_mark_cleanup_times_ms->add(ms); |
| } |
| |