1 /* 2 * Copyright (c) 2001, 2015, 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/heapRegion.hpp" 29 #include "gc/g1/survRateGroup.hpp" 30 #include "logging/log.hpp" 31 #include "memory/allocation.hpp" 32 33 SurvRateGroup::SurvRateGroup() : 34 _stats_arrays_length(0), 35 _accum_surv_rate_pred(NULL), 36 _last_pred(0.0), 37 _surv_rate_predictors(NULL), 38 _num_added_regions(0) { 39 reset(); 40 start_adding_regions(); 41 } 42 43 void SurvRateGroup::reset() { 44 _last_pred = 0.0; 45 // the following will set up the arrays with length 1 46 _num_added_regions = 1; 47 48 // The call to stop_adding_regions() will use "new" to refill 49 // the _surv_rate_pred array, so we need to make sure to call 50 // "delete". 51 for (size_t i = 0; i < _stats_arrays_length; ++i) { 52 delete _surv_rate_predictors[i]; 53 } 54 _stats_arrays_length = 0; 55 56 stop_adding_regions(); 57 58 // Seed initial _surv_rate_pred and _accum_surv_rate_pred values 59 guarantee(_stats_arrays_length == 1, "invariant" ); 60 guarantee(_surv_rate_predictors[0] != NULL, "invariant" ); 61 const double initial_surv_rate = 0.4; 62 _surv_rate_predictors[0]->add(initial_surv_rate); 63 _last_pred = _accum_surv_rate_pred[0] = initial_surv_rate; 64 65 _num_added_regions = 0; 66 } 67 68 void SurvRateGroup::start_adding_regions() { 69 _num_added_regions = 0; 70 } 71 72 void SurvRateGroup::stop_adding_regions() { 73 if (_num_added_regions > _stats_arrays_length) { 74 _accum_surv_rate_pred = REALLOC_C_HEAP_ARRAY(double, _accum_surv_rate_pred, _num_added_regions, mtGC); 75 _surv_rate_predictors = REALLOC_C_HEAP_ARRAY(TruncatedSeq*, _surv_rate_predictors, _num_added_regions, mtGC); 76 77 for (size_t i = _stats_arrays_length; i < _num_added_regions; ++i) { 78 _surv_rate_predictors[i] = new TruncatedSeq(10); 79 } 80 81 _stats_arrays_length = _num_added_regions; 82 } 83 } 84 85 void SurvRateGroup::record_surviving_words(int age_in_group, size_t surv_words) { 86 guarantee(0 <= age_in_group && (size_t)age_in_group < _num_added_regions, 87 "age_in_group is %d not between 0 and " SIZE_FORMAT, age_in_group, _num_added_regions); 88 89 double surv_rate = (double)surv_words / HeapRegion::GrainWords; 90 _surv_rate_predictors[age_in_group]->add(surv_rate); 91 } 92 93 void SurvRateGroup::all_surviving_words_recorded(const G1Predictions& predictor, bool update_predictors) { 94 if (update_predictors) { 95 fill_in_last_surv_rates(); 96 } 97 finalize_predictions(predictor); 98 } 99 100 void SurvRateGroup::fill_in_last_surv_rates() { 101 if (_num_added_regions > 0) { // conservative 102 double surv_rate = _surv_rate_predictors[_num_added_regions-1]->last(); 103 for (size_t i = _num_added_regions; i < _stats_arrays_length; ++i) { 104 _surv_rate_predictors[i]->add(surv_rate); 105 } 106 } 107 } 108 109 void SurvRateGroup::finalize_predictions(const G1Predictions& predictor) { 110 double accum = 0.0; 111 double pred = 0.0; 112 for (size_t i = 0; i < _stats_arrays_length; ++i) { 113 pred = predictor.get_new_unit_prediction(_surv_rate_predictors[i]); 114 accum += pred; 115 _accum_surv_rate_pred[i] = accum; 116 } 117 _last_pred = pred; 118 }