1 /* 2 * Copyright (c) 2001, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "gc/g1/g1CollectedHeap.inline.hpp" 27 #include "gc/g1/g1Predictions.hpp" 28 #include "gc/g1/g1SurvRateGroup.hpp" 29 #include "logging/log.hpp" 30 #include "memory/allocation.hpp" 31 32 G1SurvRateGroup::G1SurvRateGroup() : 33 _stats_arrays_length(0), 34 _accum_surv_rate_pred(NULL), 35 _last_pred(0.0), 36 _surv_rate_predictors(NULL), 37 _num_added_regions(0) { 38 reset(); 39 start_adding_regions(); 40 } 41 42 void G1SurvRateGroup::reset() { 43 _last_pred = 0.0; 44 // the following will set up the arrays with length 1 45 _num_added_regions = 1; 46 47 // The call to stop_adding_regions() will use "new" to refill 48 // the _surv_rate_pred array, so we need to make sure to call 49 // "delete". 50 for (size_t i = 0; i < _stats_arrays_length; ++i) { 51 delete _surv_rate_predictors[i]; 52 } 53 _stats_arrays_length = 0; 54 55 stop_adding_regions(); 56 57 // Seed initial _surv_rate_pred and _accum_surv_rate_pred values 58 guarantee(_stats_arrays_length == 1, "invariant" ); 59 guarantee(_surv_rate_predictors[0] != NULL, "invariant" ); 60 const double initial_surv_rate = 0.4; 61 _surv_rate_predictors[0]->add(initial_surv_rate); 62 _last_pred = _accum_surv_rate_pred[0] = initial_surv_rate; 63 64 _num_added_regions = 0; 65 } 66 67 void G1SurvRateGroup::start_adding_regions() { 68 _num_added_regions = 0; 69 } 70 71 void G1SurvRateGroup::stop_adding_regions() { 72 if (_num_added_regions > _stats_arrays_length) { 73 _accum_surv_rate_pred = REALLOC_C_HEAP_ARRAY(double, _accum_surv_rate_pred, _num_added_regions, mtGC); 74 _surv_rate_predictors = REALLOC_C_HEAP_ARRAY(TruncatedSeq*, _surv_rate_predictors, _num_added_regions, mtGC); 75 76 for (size_t i = _stats_arrays_length; i < _num_added_regions; ++i) { 77 _surv_rate_predictors[i] = new TruncatedSeq(10); 78 } 79 80 _stats_arrays_length = _num_added_regions; 81 } 82 } 83 84 void G1SurvRateGroup::record_surviving_words(int age_in_group, double surv_rate) { 85 guarantee(0 <= age_in_group && (size_t)age_in_group < _num_added_regions, 86 "age_in_group is %d not between 0 and " SIZE_FORMAT, age_in_group, _num_added_regions); 87 _surv_rate_predictors[age_in_group]->add(surv_rate); 88 } 89 90 void G1SurvRateGroup::all_surviving_words_recorded(const G1Predictions& predictor, bool update_predictors) { 91 if (update_predictors) { 92 fill_in_last_surv_rates(); 93 } 94 finalize_predictions(predictor); 95 } 96 97 void G1SurvRateGroup::fill_in_last_surv_rates() { 98 if (_num_added_regions > 0) { // conservative 99 double surv_rate = _surv_rate_predictors[_num_added_regions-1]->last(); 100 for (size_t i = _num_added_regions; i < _stats_arrays_length; ++i) { 101 _surv_rate_predictors[i]->add(surv_rate); 102 } 103 } 104 } 105 106 void G1SurvRateGroup::finalize_predictions(const G1Predictions& predictor) { 107 double accum = 0.0; 108 double pred = 0.0; 109 for (size_t i = 0; i < _stats_arrays_length; ++i) { 110 pred = predictor.predict_in_unit_interval(_surv_rate_predictors[i]); 111 accum += pred; 112 _accum_surv_rate_pred[i] = accum; 113 } 114 _last_pred = pred; 115 }