rev 59839 : imported patch 8247748-use-default-alpha-ihop

   1 /*
   2  * Copyright (c) 2015, 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/g1IHOPControl.hpp"
  28 #include "gc/g1/g1Predictions.hpp"
  29 #include "gc/g1/g1Trace.hpp"
  30 #include "logging/log.hpp"
  31 
  32 G1IHOPControl::G1IHOPControl(double initial_ihop_percent) :
  33   _initial_ihop_percent(initial_ihop_percent),
  34   _target_occupancy(0),
  35   _last_allocation_time_s(0.0),
  36   _last_allocated_bytes(0)
  37 {
  38   assert(_initial_ihop_percent >= 0.0 && _initial_ihop_percent <= 100.0, "Initial IHOP value must be between 0 and 100 but is %.3f", initial_ihop_percent);
  39 }
  40 
  41 void G1IHOPControl::update_target_occupancy(size_t new_target_occupancy) {
  42   log_debug(gc, ihop)("Target occupancy update: old: " SIZE_FORMAT "B, new: " SIZE_FORMAT "B",
  43                       _target_occupancy, new_target_occupancy);
  44   _target_occupancy = new_target_occupancy;
  45 }
  46 
  47 void G1IHOPControl::update_allocation_info(double allocation_time_s, size_t allocated_bytes, size_t additional_buffer_size) {
  48   assert(allocation_time_s >= 0.0, "Allocation time must be positive but is %.3f", allocation_time_s);
  49 
  50   _last_allocation_time_s = allocation_time_s;
  51   _last_allocated_bytes = allocated_bytes;
  52 }
  53 
  54 void G1IHOPControl::print() {
  55   assert(_target_occupancy > 0, "Target occupancy still not updated yet.");
  56   size_t cur_conc_mark_start_threshold = get_conc_mark_start_threshold();
  57   log_debug(gc, ihop)("Basic information (value update), threshold: " SIZE_FORMAT "B (%1.2f), target occupancy: " SIZE_FORMAT "B, current occupancy: " SIZE_FORMAT "B, "
  58                       "recent allocation size: " SIZE_FORMAT "B, recent allocation duration: %1.2fms, recent old gen allocation rate: %1.2fB/s, recent marking phase length: %1.2fms",
  59                       cur_conc_mark_start_threshold,
  60                       percent_of(cur_conc_mark_start_threshold, _target_occupancy),
  61                       _target_occupancy,
  62                       G1CollectedHeap::heap()->used(),
  63                       _last_allocated_bytes,
  64                       _last_allocation_time_s * 1000.0,
  65                       _last_allocation_time_s > 0.0 ? _last_allocated_bytes / _last_allocation_time_s : 0.0,
  66                       last_marking_length_s() * 1000.0);
  67 }
  68 
  69 void G1IHOPControl::send_trace_event(G1NewTracer* tracer) {
  70   assert(_target_occupancy > 0, "Target occupancy still not updated yet.");
  71   tracer->report_basic_ihop_statistics(get_conc_mark_start_threshold(),
  72                                        _target_occupancy,
  73                                        G1CollectedHeap::heap()->used(),
  74                                        _last_allocated_bytes,
  75                                        _last_allocation_time_s,
  76                                        last_marking_length_s());
  77 }
  78 
  79 G1StaticIHOPControl::G1StaticIHOPControl(double ihop_percent) :
  80   G1IHOPControl(ihop_percent),
  81   _last_marking_length_s(0.0) {
  82 }
  83 
  84 G1AdaptiveIHOPControl::G1AdaptiveIHOPControl(double ihop_percent,
  85                                              G1Predictions const* predictor,
  86                                              size_t heap_reserve_percent,
  87                                              size_t heap_waste_percent) :
  88   G1IHOPControl(ihop_percent),
  89   _heap_reserve_percent(heap_reserve_percent),
  90   _heap_waste_percent(heap_waste_percent),
  91   _predictor(predictor),
  92   _marking_times_s(10, 0.95),
  93   _allocation_rate_s(10, 0.95),
  94   _last_unrestrained_young_size(0)
  95 {
  96 }
  97 
  98 size_t G1AdaptiveIHOPControl::actual_target_threshold() const {
  99   guarantee(_target_occupancy > 0, "Target occupancy still not updated yet.");
 100   // The actual target threshold takes the heap reserve and the expected waste in
 101   // free space  into account.
 102   // _heap_reserve is that part of the total heap capacity that is reserved for
 103   // eventual promotion failure.
 104   // _heap_waste is the amount of space will never be reclaimed in any
 105   // heap, so can not be used for allocation during marking and must always be
 106   // considered.
 107 
 108   double safe_total_heap_percentage = MIN2((double)(_heap_reserve_percent + _heap_waste_percent), 100.0);
 109 
 110   return (size_t)MIN2(
 111     G1CollectedHeap::heap()->max_capacity() * (100.0 - safe_total_heap_percentage) / 100.0,
 112     _target_occupancy * (100.0 - _heap_waste_percent) / 100.0
 113     );
 114 }
 115 
 116 double G1AdaptiveIHOPControl::predict(TruncatedSeq const* seq) const {
 117   return _predictor->predict_zero_bounded(seq);
 118 }
 119 
 120 bool G1AdaptiveIHOPControl::have_enough_data_for_prediction() const {
 121   return ((size_t)_marking_times_s.num() >= G1AdaptiveIHOPNumInitialSamples) &&
 122          ((size_t)_allocation_rate_s.num() >= G1AdaptiveIHOPNumInitialSamples);
 123 }
 124 
 125 size_t G1AdaptiveIHOPControl::get_conc_mark_start_threshold() {
 126   if (have_enough_data_for_prediction()) {
 127     double pred_marking_time = predict(&_marking_times_s);
 128     double pred_promotion_rate = predict(&_allocation_rate_s);
 129     size_t pred_promotion_size = (size_t)(pred_marking_time * pred_promotion_rate);
 130 
 131     size_t predicted_needed_bytes_during_marking =
 132       pred_promotion_size +
 133       // In reality we would need the maximum size of the young gen during
 134       // marking. This is a conservative estimate.
 135       _last_unrestrained_young_size;
 136 
 137     size_t internal_threshold = actual_target_threshold();
 138     size_t predicted_initiating_threshold = predicted_needed_bytes_during_marking < internal_threshold ?
 139                                             internal_threshold - predicted_needed_bytes_during_marking :
 140                                             0;
 141     return predicted_initiating_threshold;
 142   } else {
 143     // Use the initial value.
 144     return (size_t)(_initial_ihop_percent * _target_occupancy / 100.0);
 145   }
 146 }
 147 
 148 void G1AdaptiveIHOPControl::update_allocation_info(double allocation_time_s,
 149                                                    size_t allocated_bytes,
 150                                                    size_t additional_buffer_size) {
 151   G1IHOPControl::update_allocation_info(allocation_time_s, allocated_bytes, additional_buffer_size);
 152 
 153   double allocation_rate = (double) allocated_bytes / allocation_time_s;
 154   _allocation_rate_s.add(allocation_rate);
 155 
 156   _last_unrestrained_young_size = additional_buffer_size;
 157 }
 158 
 159 void G1AdaptiveIHOPControl::update_marking_length(double marking_length_s) {
 160    assert(marking_length_s >= 0.0, "Marking length must be larger than zero but is %.3f", marking_length_s);
 161   _marking_times_s.add(marking_length_s);
 162 }
 163 
 164 void G1AdaptiveIHOPControl::print() {
 165   G1IHOPControl::print();
 166   size_t actual_target = actual_target_threshold();
 167   log_debug(gc, ihop)("Adaptive IHOP information (value update), threshold: " SIZE_FORMAT "B (%1.2f), internal target occupancy: " SIZE_FORMAT "B, "
 168                       "occupancy: " SIZE_FORMAT "B, additional buffer size: " SIZE_FORMAT "B, predicted old gen allocation rate: %1.2fB/s, "
 169                       "predicted marking phase length: %1.2fms, prediction active: %s",
 170                       get_conc_mark_start_threshold(),
 171                       percent_of(get_conc_mark_start_threshold(), actual_target),
 172                       actual_target,
 173                       G1CollectedHeap::heap()->used(),
 174                       _last_unrestrained_young_size,
 175                       predict(&_allocation_rate_s),
 176                       predict(&_marking_times_s) * 1000.0,
 177                       have_enough_data_for_prediction() ? "true" : "false");
 178 }
 179 
 180 void G1AdaptiveIHOPControl::send_trace_event(G1NewTracer* tracer) {
 181   G1IHOPControl::send_trace_event(tracer);
 182   tracer->report_adaptive_ihop_statistics(get_conc_mark_start_threshold(),
 183                                           actual_target_threshold(),
 184                                           G1CollectedHeap::heap()->used(),
 185                                           _last_unrestrained_young_size,
 186                                           predict(&_allocation_rate_s),
 187                                           predict(&_marking_times_s),
 188                                           have_enough_data_for_prediction());
 189 }
--- EOF ---