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1 /* |
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2 * Copyright 2001-2007 Sun Microsystems, Inc. All Rights Reserved. |
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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4 * |
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5 * This code is free software; you can redistribute it and/or modify it |
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6 * under the terms of the GNU General Public License version 2 only, as |
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7 * published by the Free Software Foundation. |
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8 * |
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9 * This code is distributed in the hope that it will be useful, but WITHOUT |
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10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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12 * version 2 for more details (a copy is included in the LICENSE file that |
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13 * accompanied this code). |
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14 * |
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15 * You should have received a copy of the GNU General Public License version |
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16 * 2 along with this work; if not, write to the Free Software Foundation, |
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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18 * |
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19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
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20 * CA 95054 USA or visit www.sun.com if you need additional information or |
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21 * have any questions. |
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22 * |
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23 */ |
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24 |
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25 # include "incls/_precompiled.incl" |
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26 # include "incls/_psYoungGen.cpp.incl" |
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27 |
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28 PSYoungGen::PSYoungGen(size_t initial_size, |
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29 size_t min_size, |
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30 size_t max_size) : |
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31 _init_gen_size(initial_size), |
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32 _min_gen_size(min_size), |
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33 _max_gen_size(max_size) |
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34 {} |
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35 |
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36 void PSYoungGen::initialize_virtual_space(ReservedSpace rs, size_t alignment) { |
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37 assert(_init_gen_size != 0, "Should have a finite size"); |
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38 _virtual_space = new PSVirtualSpace(rs, alignment); |
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39 if (!_virtual_space->expand_by(_init_gen_size)) { |
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40 vm_exit_during_initialization("Could not reserve enough space for " |
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41 "object heap"); |
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42 } |
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43 } |
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44 |
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45 void PSYoungGen::initialize(ReservedSpace rs, size_t alignment) { |
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46 initialize_virtual_space(rs, alignment); |
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47 initialize_work(); |
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48 } |
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49 |
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50 void PSYoungGen::initialize_work() { |
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51 |
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52 _reserved = MemRegion((HeapWord*)_virtual_space->low_boundary(), |
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53 (HeapWord*)_virtual_space->high_boundary()); |
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54 |
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55 MemRegion cmr((HeapWord*)_virtual_space->low(), |
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56 (HeapWord*)_virtual_space->high()); |
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57 Universe::heap()->barrier_set()->resize_covered_region(cmr); |
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58 |
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59 if (UseNUMA) { |
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60 _eden_space = new MutableNUMASpace(); |
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61 } else { |
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62 _eden_space = new MutableSpace(); |
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63 } |
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64 _from_space = new MutableSpace(); |
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65 _to_space = new MutableSpace(); |
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66 |
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67 if (_eden_space == NULL || _from_space == NULL || _to_space == NULL) { |
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68 vm_exit_during_initialization("Could not allocate a young gen space"); |
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69 } |
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70 |
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71 // Allocate the mark sweep views of spaces |
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72 _eden_mark_sweep = |
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73 new PSMarkSweepDecorator(_eden_space, NULL, MarkSweepDeadRatio); |
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74 _from_mark_sweep = |
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75 new PSMarkSweepDecorator(_from_space, NULL, MarkSweepDeadRatio); |
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76 _to_mark_sweep = |
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77 new PSMarkSweepDecorator(_to_space, NULL, MarkSweepDeadRatio); |
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78 |
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79 if (_eden_mark_sweep == NULL || |
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80 _from_mark_sweep == NULL || |
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81 _to_mark_sweep == NULL) { |
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82 vm_exit_during_initialization("Could not complete allocation" |
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83 " of the young generation"); |
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84 } |
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85 |
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86 // Generation Counters - generation 0, 3 subspaces |
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87 _gen_counters = new PSGenerationCounters("new", 0, 3, _virtual_space); |
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88 |
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89 // Compute maximum space sizes for performance counters |
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90 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
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91 size_t alignment = heap->intra_generation_alignment(); |
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92 size_t size = _virtual_space->reserved_size(); |
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93 |
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94 size_t max_survivor_size; |
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95 size_t max_eden_size; |
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96 |
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97 if (UseAdaptiveSizePolicy) { |
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98 max_survivor_size = size / MinSurvivorRatio; |
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99 |
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100 // round the survivor space size down to the nearest alignment |
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101 // and make sure its size is greater than 0. |
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102 max_survivor_size = align_size_down(max_survivor_size, alignment); |
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103 max_survivor_size = MAX2(max_survivor_size, alignment); |
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104 |
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105 // set the maximum size of eden to be the size of the young gen |
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106 // less two times the minimum survivor size. The minimum survivor |
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107 // size for UseAdaptiveSizePolicy is one alignment. |
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108 max_eden_size = size - 2 * alignment; |
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109 } else { |
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110 max_survivor_size = size / InitialSurvivorRatio; |
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111 |
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112 // round the survivor space size down to the nearest alignment |
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113 // and make sure its size is greater than 0. |
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114 max_survivor_size = align_size_down(max_survivor_size, alignment); |
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115 max_survivor_size = MAX2(max_survivor_size, alignment); |
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116 |
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117 // set the maximum size of eden to be the size of the young gen |
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118 // less two times the survivor size when the generation is 100% |
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119 // committed. The minimum survivor size for -UseAdaptiveSizePolicy |
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120 // is dependent on the committed portion (current capacity) of the |
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121 // generation - the less space committed, the smaller the survivor |
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122 // space, possibly as small as an alignment. However, we are interested |
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123 // in the case where the young generation is 100% committed, as this |
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124 // is the point where eden reachs its maximum size. At this point, |
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125 // the size of a survivor space is max_survivor_size. |
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126 max_eden_size = size - 2 * max_survivor_size; |
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127 } |
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128 |
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129 _eden_counters = new SpaceCounters("eden", 0, max_eden_size, _eden_space, |
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130 _gen_counters); |
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131 _from_counters = new SpaceCounters("s0", 1, max_survivor_size, _from_space, |
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132 _gen_counters); |
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133 _to_counters = new SpaceCounters("s1", 2, max_survivor_size, _to_space, |
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134 _gen_counters); |
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135 |
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136 compute_initial_space_boundaries(); |
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137 } |
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138 |
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139 void PSYoungGen::compute_initial_space_boundaries() { |
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140 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
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141 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
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142 |
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143 // Compute sizes |
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144 size_t alignment = heap->intra_generation_alignment(); |
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145 size_t size = _virtual_space->committed_size(); |
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146 |
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147 size_t survivor_size = size / InitialSurvivorRatio; |
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148 survivor_size = align_size_down(survivor_size, alignment); |
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149 // ... but never less than an alignment |
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150 survivor_size = MAX2(survivor_size, alignment); |
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151 |
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152 // Young generation is eden + 2 survivor spaces |
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153 size_t eden_size = size - (2 * survivor_size); |
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154 |
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155 // Now go ahead and set 'em. |
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156 set_space_boundaries(eden_size, survivor_size); |
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157 space_invariants(); |
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158 |
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159 if (UsePerfData) { |
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160 _eden_counters->update_capacity(); |
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161 _from_counters->update_capacity(); |
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162 _to_counters->update_capacity(); |
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163 } |
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164 } |
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165 |
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166 void PSYoungGen::set_space_boundaries(size_t eden_size, size_t survivor_size) { |
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167 assert(eden_size < _virtual_space->committed_size(), "just checking"); |
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168 assert(eden_size > 0 && survivor_size > 0, "just checking"); |
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169 |
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170 // Initial layout is Eden, to, from. After swapping survivor spaces, |
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171 // that leaves us with Eden, from, to, which is step one in our two |
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172 // step resize-with-live-data procedure. |
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173 char *eden_start = _virtual_space->low(); |
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174 char *to_start = eden_start + eden_size; |
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175 char *from_start = to_start + survivor_size; |
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176 char *from_end = from_start + survivor_size; |
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177 |
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178 assert(from_end == _virtual_space->high(), "just checking"); |
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179 assert(is_object_aligned((intptr_t)eden_start), "checking alignment"); |
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180 assert(is_object_aligned((intptr_t)to_start), "checking alignment"); |
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181 assert(is_object_aligned((intptr_t)from_start), "checking alignment"); |
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182 |
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183 MemRegion eden_mr((HeapWord*)eden_start, (HeapWord*)to_start); |
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184 MemRegion to_mr ((HeapWord*)to_start, (HeapWord*)from_start); |
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185 MemRegion from_mr((HeapWord*)from_start, (HeapWord*)from_end); |
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186 |
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187 eden_space()->initialize(eden_mr, true); |
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188 to_space()->initialize(to_mr , true); |
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189 from_space()->initialize(from_mr, true); |
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190 } |
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191 |
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192 #ifndef PRODUCT |
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193 void PSYoungGen::space_invariants() { |
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194 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
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195 const size_t alignment = heap->intra_generation_alignment(); |
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196 |
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197 // Currently, our eden size cannot shrink to zero |
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198 guarantee(eden_space()->capacity_in_bytes() >= alignment, "eden too small"); |
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199 guarantee(from_space()->capacity_in_bytes() >= alignment, "from too small"); |
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200 guarantee(to_space()->capacity_in_bytes() >= alignment, "to too small"); |
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201 |
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202 // Relationship of spaces to each other |
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203 char* eden_start = (char*)eden_space()->bottom(); |
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204 char* eden_end = (char*)eden_space()->end(); |
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205 char* from_start = (char*)from_space()->bottom(); |
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206 char* from_end = (char*)from_space()->end(); |
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207 char* to_start = (char*)to_space()->bottom(); |
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208 char* to_end = (char*)to_space()->end(); |
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209 |
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210 guarantee(eden_start >= _virtual_space->low(), "eden bottom"); |
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211 guarantee(eden_start < eden_end, "eden space consistency"); |
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212 guarantee(from_start < from_end, "from space consistency"); |
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213 guarantee(to_start < to_end, "to space consistency"); |
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214 |
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215 // Check whether from space is below to space |
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216 if (from_start < to_start) { |
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217 // Eden, from, to |
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218 guarantee(eden_end <= from_start, "eden/from boundary"); |
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219 guarantee(from_end <= to_start, "from/to boundary"); |
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220 guarantee(to_end <= _virtual_space->high(), "to end"); |
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221 } else { |
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222 // Eden, to, from |
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223 guarantee(eden_end <= to_start, "eden/to boundary"); |
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224 guarantee(to_end <= from_start, "to/from boundary"); |
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225 guarantee(from_end <= _virtual_space->high(), "from end"); |
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226 } |
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227 |
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228 // More checks that the virtual space is consistent with the spaces |
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229 assert(_virtual_space->committed_size() >= |
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230 (eden_space()->capacity_in_bytes() + |
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231 to_space()->capacity_in_bytes() + |
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232 from_space()->capacity_in_bytes()), "Committed size is inconsistent"); |
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233 assert(_virtual_space->committed_size() <= _virtual_space->reserved_size(), |
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234 "Space invariant"); |
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235 char* eden_top = (char*)eden_space()->top(); |
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236 char* from_top = (char*)from_space()->top(); |
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237 char* to_top = (char*)to_space()->top(); |
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238 assert(eden_top <= _virtual_space->high(), "eden top"); |
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239 assert(from_top <= _virtual_space->high(), "from top"); |
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240 assert(to_top <= _virtual_space->high(), "to top"); |
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241 |
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242 _virtual_space->verify(); |
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243 } |
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244 #endif |
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245 |
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246 void PSYoungGen::resize(size_t eden_size, size_t survivor_size) { |
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247 // Resize the generation if needed. If the generation resize |
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248 // reports false, do not attempt to resize the spaces. |
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249 if (resize_generation(eden_size, survivor_size)) { |
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250 // Then we lay out the spaces inside the generation |
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251 resize_spaces(eden_size, survivor_size); |
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252 |
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253 space_invariants(); |
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254 |
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255 if (PrintAdaptiveSizePolicy && Verbose) { |
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256 gclog_or_tty->print_cr("Young generation size: " |
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257 "desired eden: " SIZE_FORMAT " survivor: " SIZE_FORMAT |
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258 " used: " SIZE_FORMAT " capacity: " SIZE_FORMAT |
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259 " gen limits: " SIZE_FORMAT " / " SIZE_FORMAT, |
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260 eden_size, survivor_size, used_in_bytes(), capacity_in_bytes(), |
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261 _max_gen_size, min_gen_size()); |
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262 } |
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263 } |
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264 } |
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265 |
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266 |
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267 bool PSYoungGen::resize_generation(size_t eden_size, size_t survivor_size) { |
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268 const size_t alignment = _virtual_space->alignment(); |
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269 size_t orig_size = _virtual_space->committed_size(); |
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270 bool size_changed = false; |
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271 |
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272 // There used to be this guarantee there. |
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273 // guarantee ((eden_size + 2*survivor_size) <= _max_gen_size, "incorrect input arguments"); |
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274 // Code below forces this requirement. In addition the desired eden |
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275 // size and disired survivor sizes are desired goals and may |
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276 // exceed the total generation size. |
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277 |
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278 assert(min_gen_size() <= orig_size && orig_size <= max_size(), "just checking"); |
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279 |
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280 // Adjust new generation size |
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281 const size_t eden_plus_survivors = |
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282 align_size_up(eden_size + 2 * survivor_size, alignment); |
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283 size_t desired_size = MAX2(MIN2(eden_plus_survivors, max_size()), |
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284 min_gen_size()); |
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285 assert(desired_size <= max_size(), "just checking"); |
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286 |
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287 if (desired_size > orig_size) { |
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288 // Grow the generation |
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289 size_t change = desired_size - orig_size; |
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290 assert(change % alignment == 0, "just checking"); |
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291 if (!_virtual_space->expand_by(change)) { |
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292 return false; // Error if we fail to resize! |
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293 } |
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294 |
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295 size_changed = true; |
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296 } else if (desired_size < orig_size) { |
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297 size_t desired_change = orig_size - desired_size; |
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298 assert(desired_change % alignment == 0, "just checking"); |
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299 |
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300 desired_change = limit_gen_shrink(desired_change); |
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301 |
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302 if (desired_change > 0) { |
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303 virtual_space()->shrink_by(desired_change); |
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304 reset_survivors_after_shrink(); |
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305 |
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306 size_changed = true; |
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307 } |
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308 } else { |
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309 if (Verbose && PrintGC) { |
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310 if (orig_size == gen_size_limit()) { |
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311 gclog_or_tty->print_cr("PSYoung generation size at maximum: " |
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312 SIZE_FORMAT "K", orig_size/K); |
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313 } else if (orig_size == min_gen_size()) { |
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314 gclog_or_tty->print_cr("PSYoung generation size at minium: " |
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315 SIZE_FORMAT "K", orig_size/K); |
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316 } |
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317 } |
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318 } |
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319 |
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320 if (size_changed) { |
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321 post_resize(); |
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322 |
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323 if (Verbose && PrintGC) { |
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324 size_t current_size = _virtual_space->committed_size(); |
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325 gclog_or_tty->print_cr("PSYoung generation size changed: " |
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326 SIZE_FORMAT "K->" SIZE_FORMAT "K", |
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327 orig_size/K, current_size/K); |
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328 } |
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329 } |
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330 |
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331 guarantee(eden_plus_survivors <= _virtual_space->committed_size() || |
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332 _virtual_space->committed_size() == max_size(), "Sanity"); |
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333 |
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334 return true; |
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335 } |
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336 |
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337 |
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338 void PSYoungGen::resize_spaces(size_t requested_eden_size, |
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339 size_t requested_survivor_size) { |
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340 assert(UseAdaptiveSizePolicy, "sanity check"); |
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341 assert(requested_eden_size > 0 && requested_survivor_size > 0, |
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342 "just checking"); |
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343 |
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344 // We require eden and to space to be empty |
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345 if ((!eden_space()->is_empty()) || (!to_space()->is_empty())) { |
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346 return; |
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347 } |
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348 |
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349 if (PrintAdaptiveSizePolicy && Verbose) { |
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350 gclog_or_tty->print_cr("PSYoungGen::resize_spaces(requested_eden_size: " |
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351 SIZE_FORMAT |
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352 ", requested_survivor_size: " SIZE_FORMAT ")", |
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353 requested_eden_size, requested_survivor_size); |
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354 gclog_or_tty->print_cr(" eden: [" PTR_FORMAT ".." PTR_FORMAT ") " |
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355 SIZE_FORMAT, |
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356 eden_space()->bottom(), |
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357 eden_space()->end(), |
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358 pointer_delta(eden_space()->end(), |
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359 eden_space()->bottom(), |
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360 sizeof(char))); |
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361 gclog_or_tty->print_cr(" from: [" PTR_FORMAT ".." PTR_FORMAT ") " |
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362 SIZE_FORMAT, |
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363 from_space()->bottom(), |
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364 from_space()->end(), |
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365 pointer_delta(from_space()->end(), |
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366 from_space()->bottom(), |
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367 sizeof(char))); |
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368 gclog_or_tty->print_cr(" to: [" PTR_FORMAT ".." PTR_FORMAT ") " |
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369 SIZE_FORMAT, |
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370 to_space()->bottom(), |
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371 to_space()->end(), |
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372 pointer_delta( to_space()->end(), |
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373 to_space()->bottom(), |
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374 sizeof(char))); |
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375 } |
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376 |
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377 // There's nothing to do if the new sizes are the same as the current |
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378 if (requested_survivor_size == to_space()->capacity_in_bytes() && |
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379 requested_survivor_size == from_space()->capacity_in_bytes() && |
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380 requested_eden_size == eden_space()->capacity_in_bytes()) { |
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381 if (PrintAdaptiveSizePolicy && Verbose) { |
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382 gclog_or_tty->print_cr(" capacities are the right sizes, returning"); |
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383 } |
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384 return; |
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385 } |
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386 |
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387 char* eden_start = (char*)eden_space()->bottom(); |
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388 char* eden_end = (char*)eden_space()->end(); |
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389 char* from_start = (char*)from_space()->bottom(); |
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390 char* from_end = (char*)from_space()->end(); |
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391 char* to_start = (char*)to_space()->bottom(); |
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392 char* to_end = (char*)to_space()->end(); |
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393 |
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394 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
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395 const size_t alignment = heap->intra_generation_alignment(); |
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396 const bool maintain_minimum = |
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397 (requested_eden_size + 2 * requested_survivor_size) <= min_gen_size(); |
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398 |
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399 // Check whether from space is below to space |
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400 if (from_start < to_start) { |
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401 // Eden, from, to |
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402 if (PrintAdaptiveSizePolicy && Verbose) { |
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403 gclog_or_tty->print_cr(" Eden, from, to:"); |
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404 } |
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405 |
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406 // Set eden |
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407 // "requested_eden_size" is a goal for the size of eden |
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408 // and may not be attainable. "eden_size" below is |
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409 // calculated based on the location of from-space and |
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410 // the goal for the size of eden. from-space is |
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411 // fixed in place because it contains live data. |
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412 // The calculation is done this way to avoid 32bit |
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413 // overflow (i.e., eden_start + requested_eden_size |
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414 // may too large for representation in 32bits). |
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415 size_t eden_size; |
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416 if (maintain_minimum) { |
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417 // Only make eden larger than the requested size if |
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418 // the minimum size of the generation has to be maintained. |
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419 // This could be done in general but policy at a higher |
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420 // level is determining a requested size for eden and that |
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421 // should be honored unless there is a fundamental reason. |
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422 eden_size = pointer_delta(from_start, |
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423 eden_start, |
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424 sizeof(char)); |
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425 } else { |
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426 eden_size = MIN2(requested_eden_size, |
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427 pointer_delta(from_start, eden_start, sizeof(char))); |
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428 } |
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429 |
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430 eden_end = eden_start + eden_size; |
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431 assert(eden_end >= eden_start, "addition overflowed") |
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432 |
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433 // To may resize into from space as long as it is clear of live data. |
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434 // From space must remain page aligned, though, so we need to do some |
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435 // extra calculations. |
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436 |
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437 // First calculate an optimal to-space |
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438 to_end = (char*)_virtual_space->high(); |
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439 to_start = (char*)pointer_delta(to_end, (char*)requested_survivor_size, |
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440 sizeof(char)); |
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441 |
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442 // Does the optimal to-space overlap from-space? |
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443 if (to_start < (char*)from_space()->end()) { |
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444 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
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445 |
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446 // Calculate the minimum offset possible for from_end |
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447 size_t from_size = pointer_delta(from_space()->top(), from_start, sizeof(char)); |
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448 |
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449 // Should we be in this method if from_space is empty? Why not the set_space method? FIX ME! |
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450 if (from_size == 0) { |
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451 from_size = alignment; |
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452 } else { |
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453 from_size = align_size_up(from_size, alignment); |
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454 } |
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455 |
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456 from_end = from_start + from_size; |
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457 assert(from_end > from_start, "addition overflow or from_size problem"); |
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458 |
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459 guarantee(from_end <= (char*)from_space()->end(), "from_end moved to the right"); |
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460 |
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461 // Now update to_start with the new from_end |
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462 to_start = MAX2(from_end, to_start); |
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463 } |
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464 |
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465 guarantee(to_start != to_end, "to space is zero sized"); |
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466 |
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467 if (PrintAdaptiveSizePolicy && Verbose) { |
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468 gclog_or_tty->print_cr(" [eden_start .. eden_end): " |
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469 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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470 eden_start, |
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471 eden_end, |
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472 pointer_delta(eden_end, eden_start, sizeof(char))); |
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473 gclog_or_tty->print_cr(" [from_start .. from_end): " |
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474 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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475 from_start, |
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476 from_end, |
|
477 pointer_delta(from_end, from_start, sizeof(char))); |
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478 gclog_or_tty->print_cr(" [ to_start .. to_end): " |
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479 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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480 to_start, |
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481 to_end, |
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482 pointer_delta( to_end, to_start, sizeof(char))); |
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483 } |
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484 } else { |
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485 // Eden, to, from |
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486 if (PrintAdaptiveSizePolicy && Verbose) { |
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487 gclog_or_tty->print_cr(" Eden, to, from:"); |
|
488 } |
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489 |
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490 // To space gets priority over eden resizing. Note that we position |
|
491 // to space as if we were able to resize from space, even though from |
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492 // space is not modified. |
|
493 // Giving eden priority was tried and gave poorer performance. |
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494 to_end = (char*)pointer_delta(_virtual_space->high(), |
|
495 (char*)requested_survivor_size, |
|
496 sizeof(char)); |
|
497 to_end = MIN2(to_end, from_start); |
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498 to_start = (char*)pointer_delta(to_end, (char*)requested_survivor_size, |
|
499 sizeof(char)); |
|
500 // if the space sizes are to be increased by several times then |
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501 // 'to_start' will point beyond the young generation. In this case |
|
502 // 'to_start' should be adjusted. |
|
503 to_start = MAX2(to_start, eden_start + alignment); |
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504 |
|
505 // Compute how big eden can be, then adjust end. |
|
506 // See comments above on calculating eden_end. |
|
507 size_t eden_size; |
|
508 if (maintain_minimum) { |
|
509 eden_size = pointer_delta(to_start, eden_start, sizeof(char)); |
|
510 } else { |
|
511 eden_size = MIN2(requested_eden_size, |
|
512 pointer_delta(to_start, eden_start, sizeof(char))); |
|
513 } |
|
514 eden_end = eden_start + eden_size; |
|
515 assert(eden_end >= eden_start, "addition overflowed") |
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516 |
|
517 // Could choose to not let eden shrink |
|
518 // to_start = MAX2(to_start, eden_end); |
|
519 |
|
520 // Don't let eden shrink down to 0 or less. |
|
521 eden_end = MAX2(eden_end, eden_start + alignment); |
|
522 to_start = MAX2(to_start, eden_end); |
|
523 |
|
524 if (PrintAdaptiveSizePolicy && Verbose) { |
|
525 gclog_or_tty->print_cr(" [eden_start .. eden_end): " |
|
526 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
|
527 eden_start, |
|
528 eden_end, |
|
529 pointer_delta(eden_end, eden_start, sizeof(char))); |
|
530 gclog_or_tty->print_cr(" [ to_start .. to_end): " |
|
531 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
|
532 to_start, |
|
533 to_end, |
|
534 pointer_delta( to_end, to_start, sizeof(char))); |
|
535 gclog_or_tty->print_cr(" [from_start .. from_end): " |
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536 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
|
537 from_start, |
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538 from_end, |
|
539 pointer_delta(from_end, from_start, sizeof(char))); |
|
540 } |
|
541 } |
|
542 |
|
543 |
|
544 guarantee((HeapWord*)from_start <= from_space()->bottom(), |
|
545 "from start moved to the right"); |
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546 guarantee((HeapWord*)from_end >= from_space()->top(), |
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547 "from end moved into live data"); |
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548 assert(is_object_aligned((intptr_t)eden_start), "checking alignment"); |
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549 assert(is_object_aligned((intptr_t)from_start), "checking alignment"); |
|
550 assert(is_object_aligned((intptr_t)to_start), "checking alignment"); |
|
551 |
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552 MemRegion edenMR((HeapWord*)eden_start, (HeapWord*)eden_end); |
|
553 MemRegion toMR ((HeapWord*)to_start, (HeapWord*)to_end); |
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554 MemRegion fromMR((HeapWord*)from_start, (HeapWord*)from_end); |
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555 |
|
556 // Let's make sure the call to initialize doesn't reset "top"! |
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557 HeapWord* old_from_top = from_space()->top(); |
|
558 |
|
559 // For PrintAdaptiveSizePolicy block below |
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560 size_t old_from = from_space()->capacity_in_bytes(); |
|
561 size_t old_to = to_space()->capacity_in_bytes(); |
|
562 |
|
563 eden_space()->initialize(edenMR, true); |
|
564 to_space()->initialize(toMR , true); |
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565 from_space()->initialize(fromMR, false); // Note, not cleared! |
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566 |
|
567 assert(from_space()->top() == old_from_top, "from top changed!"); |
|
568 |
|
569 if (PrintAdaptiveSizePolicy) { |
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570 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
|
571 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity"); |
|
572 |
|
573 gclog_or_tty->print("AdaptiveSizePolicy::survivor space sizes: " |
|
574 "collection: %d " |
|
575 "(" SIZE_FORMAT ", " SIZE_FORMAT ") -> " |
|
576 "(" SIZE_FORMAT ", " SIZE_FORMAT ") ", |
|
577 heap->total_collections(), |
|
578 old_from, old_to, |
|
579 from_space()->capacity_in_bytes(), |
|
580 to_space()->capacity_in_bytes()); |
|
581 gclog_or_tty->cr(); |
|
582 } |
|
583 } |
|
584 |
|
585 void PSYoungGen::swap_spaces() { |
|
586 MutableSpace* s = from_space(); |
|
587 _from_space = to_space(); |
|
588 _to_space = s; |
|
589 |
|
590 // Now update the decorators. |
|
591 PSMarkSweepDecorator* md = from_mark_sweep(); |
|
592 _from_mark_sweep = to_mark_sweep(); |
|
593 _to_mark_sweep = md; |
|
594 |
|
595 assert(from_mark_sweep()->space() == from_space(), "Sanity"); |
|
596 assert(to_mark_sweep()->space() == to_space(), "Sanity"); |
|
597 } |
|
598 |
|
599 size_t PSYoungGen::capacity_in_bytes() const { |
|
600 return eden_space()->capacity_in_bytes() |
|
601 + from_space()->capacity_in_bytes(); // to_space() is only used during scavenge |
|
602 } |
|
603 |
|
604 |
|
605 size_t PSYoungGen::used_in_bytes() const { |
|
606 return eden_space()->used_in_bytes() |
|
607 + from_space()->used_in_bytes(); // to_space() is only used during scavenge |
|
608 } |
|
609 |
|
610 |
|
611 size_t PSYoungGen::free_in_bytes() const { |
|
612 return eden_space()->free_in_bytes() |
|
613 + from_space()->free_in_bytes(); // to_space() is only used during scavenge |
|
614 } |
|
615 |
|
616 size_t PSYoungGen::capacity_in_words() const { |
|
617 return eden_space()->capacity_in_words() |
|
618 + from_space()->capacity_in_words(); // to_space() is only used during scavenge |
|
619 } |
|
620 |
|
621 |
|
622 size_t PSYoungGen::used_in_words() const { |
|
623 return eden_space()->used_in_words() |
|
624 + from_space()->used_in_words(); // to_space() is only used during scavenge |
|
625 } |
|
626 |
|
627 |
|
628 size_t PSYoungGen::free_in_words() const { |
|
629 return eden_space()->free_in_words() |
|
630 + from_space()->free_in_words(); // to_space() is only used during scavenge |
|
631 } |
|
632 |
|
633 void PSYoungGen::object_iterate(ObjectClosure* blk) { |
|
634 eden_space()->object_iterate(blk); |
|
635 from_space()->object_iterate(blk); |
|
636 to_space()->object_iterate(blk); |
|
637 } |
|
638 |
|
639 void PSYoungGen::precompact() { |
|
640 eden_mark_sweep()->precompact(); |
|
641 from_mark_sweep()->precompact(); |
|
642 to_mark_sweep()->precompact(); |
|
643 } |
|
644 |
|
645 void PSYoungGen::adjust_pointers() { |
|
646 eden_mark_sweep()->adjust_pointers(); |
|
647 from_mark_sweep()->adjust_pointers(); |
|
648 to_mark_sweep()->adjust_pointers(); |
|
649 } |
|
650 |
|
651 void PSYoungGen::compact() { |
|
652 eden_mark_sweep()->compact(ZapUnusedHeapArea); |
|
653 from_mark_sweep()->compact(ZapUnusedHeapArea); |
|
654 // Mark sweep stores preserved markOops in to space, don't disturb! |
|
655 to_mark_sweep()->compact(false); |
|
656 } |
|
657 |
|
658 void PSYoungGen::move_and_update(ParCompactionManager* cm) { |
|
659 PSParallelCompact::move_and_update(cm, PSParallelCompact::eden_space_id); |
|
660 PSParallelCompact::move_and_update(cm, PSParallelCompact::from_space_id); |
|
661 PSParallelCompact::move_and_update(cm, PSParallelCompact::to_space_id); |
|
662 } |
|
663 |
|
664 void PSYoungGen::print() const { print_on(tty); } |
|
665 void PSYoungGen::print_on(outputStream* st) const { |
|
666 st->print(" %-15s", "PSYoungGen"); |
|
667 if (PrintGCDetails && Verbose) { |
|
668 st->print(" total " SIZE_FORMAT ", used " SIZE_FORMAT, |
|
669 capacity_in_bytes(), used_in_bytes()); |
|
670 } else { |
|
671 st->print(" total " SIZE_FORMAT "K, used " SIZE_FORMAT "K", |
|
672 capacity_in_bytes()/K, used_in_bytes()/K); |
|
673 } |
|
674 _virtual_space->print_space_boundaries_on(st); |
|
675 st->print(" eden"); eden_space()->print_on(st); |
|
676 st->print(" from"); from_space()->print_on(st); |
|
677 st->print(" to "); to_space()->print_on(st); |
|
678 } |
|
679 |
|
680 void PSYoungGen::print_used_change(size_t prev_used) const { |
|
681 gclog_or_tty->print(" [%s:", name()); |
|
682 gclog_or_tty->print(" " SIZE_FORMAT "K" |
|
683 "->" SIZE_FORMAT "K" |
|
684 "(" SIZE_FORMAT "K)", |
|
685 prev_used / K, used_in_bytes() / K, |
|
686 capacity_in_bytes() / K); |
|
687 gclog_or_tty->print("]"); |
|
688 } |
|
689 |
|
690 size_t PSYoungGen::available_for_expansion() { |
|
691 ShouldNotReachHere(); |
|
692 return 0; |
|
693 } |
|
694 |
|
695 size_t PSYoungGen::available_for_contraction() { |
|
696 ShouldNotReachHere(); |
|
697 return 0; |
|
698 } |
|
699 |
|
700 size_t PSYoungGen::available_to_min_gen() { |
|
701 assert(virtual_space()->committed_size() >= min_gen_size(), "Invariant"); |
|
702 return virtual_space()->committed_size() - min_gen_size(); |
|
703 } |
|
704 |
|
705 // This method assumes that from-space has live data and that |
|
706 // any shrinkage of the young gen is limited by location of |
|
707 // from-space. |
|
708 size_t PSYoungGen::available_to_live() { |
|
709 size_t delta_in_survivor = 0; |
|
710 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
|
711 const size_t space_alignment = heap->intra_generation_alignment(); |
|
712 const size_t gen_alignment = heap->young_gen_alignment(); |
|
713 |
|
714 MutableSpace* space_shrinking = NULL; |
|
715 if (from_space()->end() > to_space()->end()) { |
|
716 space_shrinking = from_space(); |
|
717 } else { |
|
718 space_shrinking = to_space(); |
|
719 } |
|
720 |
|
721 // Include any space that is committed but not included in |
|
722 // the survivor spaces. |
|
723 assert(((HeapWord*)virtual_space()->high()) >= space_shrinking->end(), |
|
724 "Survivor space beyond high end"); |
|
725 size_t unused_committed = pointer_delta(virtual_space()->high(), |
|
726 space_shrinking->end(), sizeof(char)); |
|
727 |
|
728 if (space_shrinking->is_empty()) { |
|
729 // Don't let the space shrink to 0 |
|
730 assert(space_shrinking->capacity_in_bytes() >= space_alignment, |
|
731 "Space is too small"); |
|
732 delta_in_survivor = space_shrinking->capacity_in_bytes() - space_alignment; |
|
733 } else { |
|
734 delta_in_survivor = pointer_delta(space_shrinking->end(), |
|
735 space_shrinking->top(), |
|
736 sizeof(char)); |
|
737 } |
|
738 |
|
739 size_t delta_in_bytes = unused_committed + delta_in_survivor; |
|
740 delta_in_bytes = align_size_down(delta_in_bytes, gen_alignment); |
|
741 return delta_in_bytes; |
|
742 } |
|
743 |
|
744 // Return the number of bytes available for resizing down the young |
|
745 // generation. This is the minimum of |
|
746 // input "bytes" |
|
747 // bytes to the minimum young gen size |
|
748 // bytes to the size currently being used + some small extra |
|
749 size_t PSYoungGen::limit_gen_shrink(size_t bytes) { |
|
750 // Allow shrinkage into the current eden but keep eden large enough |
|
751 // to maintain the minimum young gen size |
|
752 bytes = MIN3(bytes, available_to_min_gen(), available_to_live()); |
|
753 return align_size_down(bytes, virtual_space()->alignment()); |
|
754 } |
|
755 |
|
756 void PSYoungGen::reset_after_change() { |
|
757 ShouldNotReachHere(); |
|
758 } |
|
759 |
|
760 void PSYoungGen::reset_survivors_after_shrink() { |
|
761 _reserved = MemRegion((HeapWord*)virtual_space()->low_boundary(), |
|
762 (HeapWord*)virtual_space()->high_boundary()); |
|
763 PSScavenge::reference_processor()->set_span(_reserved); |
|
764 |
|
765 MutableSpace* space_shrinking = NULL; |
|
766 if (from_space()->end() > to_space()->end()) { |
|
767 space_shrinking = from_space(); |
|
768 } else { |
|
769 space_shrinking = to_space(); |
|
770 } |
|
771 |
|
772 HeapWord* new_end = (HeapWord*)virtual_space()->high(); |
|
773 assert(new_end >= space_shrinking->bottom(), "Shrink was too large"); |
|
774 // Was there a shrink of the survivor space? |
|
775 if (new_end < space_shrinking->end()) { |
|
776 MemRegion mr(space_shrinking->bottom(), new_end); |
|
777 space_shrinking->initialize(mr, false /* clear */); |
|
778 } |
|
779 } |
|
780 |
|
781 // This method currently does not expect to expand into eden (i.e., |
|
782 // the virtual space boundaries is expected to be consistent |
|
783 // with the eden boundaries.. |
|
784 void PSYoungGen::post_resize() { |
|
785 assert_locked_or_safepoint(Heap_lock); |
|
786 assert((eden_space()->bottom() < to_space()->bottom()) && |
|
787 (eden_space()->bottom() < from_space()->bottom()), |
|
788 "Eden is assumed to be below the survivor spaces"); |
|
789 |
|
790 MemRegion cmr((HeapWord*)virtual_space()->low(), |
|
791 (HeapWord*)virtual_space()->high()); |
|
792 Universe::heap()->barrier_set()->resize_covered_region(cmr); |
|
793 space_invariants(); |
|
794 } |
|
795 |
|
796 |
|
797 |
|
798 void PSYoungGen::update_counters() { |
|
799 if (UsePerfData) { |
|
800 _eden_counters->update_all(); |
|
801 _from_counters->update_all(); |
|
802 _to_counters->update_all(); |
|
803 _gen_counters->update_all(); |
|
804 } |
|
805 } |
|
806 |
|
807 void PSYoungGen::verify(bool allow_dirty) { |
|
808 eden_space()->verify(allow_dirty); |
|
809 from_space()->verify(allow_dirty); |
|
810 to_space()->verify(allow_dirty); |
|
811 } |