1 /* |
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2 * Copyright (c) 2005, 2014, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
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22 * |
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23 */ |
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24 |
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25 #include "precompiled.hpp" |
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26 #include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp" |
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27 #include "gc_implementation/concurrentMarkSweep/cmsGCAdaptivePolicyCounters.hpp" |
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28 #include "gc_implementation/parNew/asParNewGeneration.hpp" |
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29 #include "gc_implementation/parNew/parNewGeneration.hpp" |
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30 #include "gc_implementation/shared/markSweep.inline.hpp" |
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31 #include "gc_implementation/shared/spaceDecorator.hpp" |
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32 #include "memory/defNewGeneration.inline.hpp" |
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33 #include "memory/referencePolicy.hpp" |
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34 #include "oops/markOop.inline.hpp" |
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35 #include "oops/oop.pcgc.inline.hpp" |
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36 |
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37 ASParNewGeneration::ASParNewGeneration(ReservedSpace rs, |
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38 size_t initial_byte_size, |
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39 size_t min_byte_size, |
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40 int level) : |
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41 ParNewGeneration(rs, initial_byte_size, level), |
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42 _min_gen_size(min_byte_size) {} |
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43 |
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44 const char* ASParNewGeneration::name() const { |
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45 return "adaptive size par new generation"; |
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46 } |
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47 |
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48 void ASParNewGeneration::adjust_desired_tenuring_threshold() { |
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49 assert(UseAdaptiveSizePolicy, |
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50 "Should only be used with UseAdaptiveSizePolicy"); |
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51 } |
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52 |
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53 void ASParNewGeneration::resize(size_t eden_size, size_t survivor_size) { |
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54 // Resize the generation if needed. If the generation resize |
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55 // reports false, do not attempt to resize the spaces. |
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56 if (resize_generation(eden_size, survivor_size)) { |
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57 // Then we lay out the spaces inside the generation |
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58 resize_spaces(eden_size, survivor_size); |
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59 |
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60 space_invariants(); |
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61 |
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62 if (PrintAdaptiveSizePolicy && Verbose) { |
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63 gclog_or_tty->print_cr("Young generation size: " |
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64 "desired eden: " SIZE_FORMAT " survivor: " SIZE_FORMAT |
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65 " used: " SIZE_FORMAT " capacity: " SIZE_FORMAT |
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66 " gen limits: " SIZE_FORMAT " / " SIZE_FORMAT, |
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67 eden_size, survivor_size, used(), capacity(), |
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68 max_gen_size(), min_gen_size()); |
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69 } |
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70 } |
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71 } |
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72 |
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73 size_t ASParNewGeneration::available_to_min_gen() { |
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74 assert(virtual_space()->committed_size() >= min_gen_size(), "Invariant"); |
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75 return virtual_space()->committed_size() - min_gen_size(); |
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76 } |
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77 |
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78 // This method assumes that from-space has live data and that |
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79 // any shrinkage of the young gen is limited by location of |
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80 // from-space. |
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81 size_t ASParNewGeneration::available_to_live() const { |
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82 #undef SHRINKS_AT_END_OF_EDEN |
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83 #ifdef SHRINKS_AT_END_OF_EDEN |
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84 size_t delta_in_survivor = 0; |
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85 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap(); |
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86 const size_t space_alignment = heap->intra_heap_alignment(); |
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87 const size_t gen_alignment = heap->object_heap_alignment(); |
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88 |
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89 MutableSpace* space_shrinking = NULL; |
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90 if (from_space()->end() > to_space()->end()) { |
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91 space_shrinking = from_space(); |
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92 } else { |
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93 space_shrinking = to_space(); |
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94 } |
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95 |
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96 // Include any space that is committed but not included in |
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97 // the survivor spaces. |
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98 assert(((HeapWord*)virtual_space()->high()) >= space_shrinking->end(), |
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99 "Survivor space beyond high end"); |
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100 size_t unused_committed = pointer_delta(virtual_space()->high(), |
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101 space_shrinking->end(), sizeof(char)); |
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102 |
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103 if (space_shrinking->is_empty()) { |
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104 // Don't let the space shrink to 0 |
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105 assert(space_shrinking->capacity_in_bytes() >= space_alignment, |
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106 "Space is too small"); |
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107 delta_in_survivor = space_shrinking->capacity_in_bytes() - space_alignment; |
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108 } else { |
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109 delta_in_survivor = pointer_delta(space_shrinking->end(), |
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110 space_shrinking->top(), |
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111 sizeof(char)); |
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112 } |
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113 |
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114 size_t delta_in_bytes = unused_committed + delta_in_survivor; |
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115 delta_in_bytes = align_size_down(delta_in_bytes, gen_alignment); |
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116 return delta_in_bytes; |
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117 #else |
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118 // The only space available for shrinking is in to-space if it |
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119 // is above from-space. |
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120 if (to()->bottom() > from()->bottom()) { |
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121 const size_t alignment = os::vm_page_size(); |
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122 if (to()->capacity() < alignment) { |
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123 return 0; |
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124 } else { |
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125 return to()->capacity() - alignment; |
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126 } |
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127 } else { |
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128 return 0; |
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129 } |
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130 #endif |
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131 } |
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132 |
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133 // Return the number of bytes available for resizing down the young |
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134 // generation. This is the minimum of |
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135 // input "bytes" |
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136 // bytes to the minimum young gen size |
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137 // bytes to the size currently being used + some small extra |
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138 size_t ASParNewGeneration::limit_gen_shrink (size_t bytes) { |
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139 // Allow shrinkage into the current eden but keep eden large enough |
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140 // to maintain the minimum young gen size |
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141 bytes = MIN3(bytes, available_to_min_gen(), available_to_live()); |
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142 return align_size_down(bytes, os::vm_page_size()); |
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143 } |
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144 |
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145 // Note that the the alignment used is the OS page size as |
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146 // opposed to an alignment associated with the virtual space |
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147 // (as is done in the ASPSYoungGen/ASPSOldGen) |
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148 bool ASParNewGeneration::resize_generation(size_t eden_size, |
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149 size_t survivor_size) { |
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150 const size_t alignment = os::vm_page_size(); |
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151 size_t orig_size = virtual_space()->committed_size(); |
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152 bool size_changed = false; |
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153 |
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154 // There used to be this guarantee there. |
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155 // guarantee ((eden_size + 2*survivor_size) <= _max_gen_size, "incorrect input arguments"); |
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156 // Code below forces this requirement. In addition the desired eden |
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157 // size and desired survivor sizes are desired goals and may |
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158 // exceed the total generation size. |
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159 |
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160 assert(min_gen_size() <= orig_size && orig_size <= max_gen_size(), |
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161 "just checking"); |
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162 |
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163 // Adjust new generation size |
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164 const size_t eden_plus_survivors = |
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165 align_size_up(eden_size + 2 * survivor_size, alignment); |
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166 size_t desired_size = MAX2(MIN2(eden_plus_survivors, max_gen_size()), |
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167 min_gen_size()); |
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168 assert(desired_size <= max_gen_size(), "just checking"); |
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169 |
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170 if (desired_size > orig_size) { |
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171 // Grow the generation |
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172 size_t change = desired_size - orig_size; |
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173 assert(change % alignment == 0, "just checking"); |
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174 if (expand(change)) { |
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175 return false; // Error if we fail to resize! |
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176 } |
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177 size_changed = true; |
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178 } else if (desired_size < orig_size) { |
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179 size_t desired_change = orig_size - desired_size; |
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180 assert(desired_change % alignment == 0, "just checking"); |
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181 |
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182 desired_change = limit_gen_shrink(desired_change); |
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183 |
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184 if (desired_change > 0) { |
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185 virtual_space()->shrink_by(desired_change); |
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186 reset_survivors_after_shrink(); |
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187 |
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188 size_changed = true; |
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189 } |
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190 } else { |
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191 if (Verbose && PrintGC) { |
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192 if (orig_size == max_gen_size()) { |
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193 gclog_or_tty->print_cr("ASParNew generation size at maximum: " |
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194 SIZE_FORMAT "K", orig_size/K); |
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195 } else if (orig_size == min_gen_size()) { |
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196 gclog_or_tty->print_cr("ASParNew generation size at minium: " |
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197 SIZE_FORMAT "K", orig_size/K); |
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198 } |
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199 } |
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200 } |
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201 |
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202 if (size_changed) { |
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203 MemRegion cmr((HeapWord*)virtual_space()->low(), |
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204 (HeapWord*)virtual_space()->high()); |
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205 GenCollectedHeap::heap()->barrier_set()->resize_covered_region(cmr); |
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206 |
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207 if (Verbose && PrintGC) { |
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208 size_t current_size = virtual_space()->committed_size(); |
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209 gclog_or_tty->print_cr("ASParNew generation size changed: " |
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210 SIZE_FORMAT "K->" SIZE_FORMAT "K", |
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211 orig_size/K, current_size/K); |
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212 } |
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213 } |
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214 |
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215 guarantee(eden_plus_survivors <= virtual_space()->committed_size() || |
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216 virtual_space()->committed_size() == max_gen_size(), "Sanity"); |
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217 |
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218 return true; |
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219 } |
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220 |
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221 void ASParNewGeneration::reset_survivors_after_shrink() { |
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222 |
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223 GenCollectedHeap* gch = GenCollectedHeap::heap(); |
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224 HeapWord* new_end = (HeapWord*)virtual_space()->high(); |
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225 |
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226 if (from()->end() > to()->end()) { |
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227 assert(new_end >= from()->end(), "Shrinking past from-space"); |
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228 } else { |
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229 assert(new_end >= to()->bottom(), "Shrink was too large"); |
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230 // Was there a shrink of the survivor space? |
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231 if (new_end < to()->end()) { |
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232 MemRegion mr(to()->bottom(), new_end); |
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233 to()->initialize(mr, |
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234 SpaceDecorator::DontClear, |
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235 SpaceDecorator::DontMangle); |
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236 } |
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237 } |
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238 } |
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239 void ASParNewGeneration::resize_spaces(size_t requested_eden_size, |
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240 size_t requested_survivor_size) { |
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241 assert(UseAdaptiveSizePolicy, "sanity check"); |
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242 assert(requested_eden_size > 0 && requested_survivor_size > 0, |
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243 "just checking"); |
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244 CollectedHeap* heap = Universe::heap(); |
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245 assert(heap->kind() == CollectedHeap::GenCollectedHeap, "Sanity"); |
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246 |
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247 |
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248 // We require eden and to space to be empty |
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249 if ((!eden()->is_empty()) || (!to()->is_empty())) { |
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250 return; |
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251 } |
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252 |
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253 size_t cur_eden_size = eden()->capacity(); |
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254 |
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255 if (PrintAdaptiveSizePolicy && Verbose) { |
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256 gclog_or_tty->print_cr("ASParNew::resize_spaces(requested_eden_size: " |
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257 SIZE_FORMAT |
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258 ", requested_survivor_size: " SIZE_FORMAT ")", |
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259 requested_eden_size, requested_survivor_size); |
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260 gclog_or_tty->print_cr(" eden: [" PTR_FORMAT ".." PTR_FORMAT ") " |
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261 SIZE_FORMAT, |
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262 p2i(eden()->bottom()), |
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263 p2i(eden()->end()), |
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264 pointer_delta(eden()->end(), |
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265 eden()->bottom(), |
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266 sizeof(char))); |
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267 gclog_or_tty->print_cr(" from: [" PTR_FORMAT ".." PTR_FORMAT ") " |
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268 SIZE_FORMAT, |
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269 p2i(from()->bottom()), |
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270 p2i(from()->end()), |
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271 pointer_delta(from()->end(), |
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272 from()->bottom(), |
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273 sizeof(char))); |
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274 gclog_or_tty->print_cr(" to: [" PTR_FORMAT ".." PTR_FORMAT ") " |
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275 SIZE_FORMAT, |
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276 p2i(to()->bottom()), |
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277 p2i(to()->end()), |
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278 pointer_delta( to()->end(), |
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279 to()->bottom(), |
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280 sizeof(char))); |
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281 } |
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282 |
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283 // There's nothing to do if the new sizes are the same as the current |
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284 if (requested_survivor_size == to()->capacity() && |
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285 requested_survivor_size == from()->capacity() && |
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286 requested_eden_size == eden()->capacity()) { |
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287 if (PrintAdaptiveSizePolicy && Verbose) { |
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288 gclog_or_tty->print_cr(" capacities are the right sizes, returning"); |
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289 } |
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290 return; |
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291 } |
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292 |
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293 char* eden_start = (char*)eden()->bottom(); |
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294 char* eden_end = (char*)eden()->end(); |
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295 char* from_start = (char*)from()->bottom(); |
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296 char* from_end = (char*)from()->end(); |
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297 char* to_start = (char*)to()->bottom(); |
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298 char* to_end = (char*)to()->end(); |
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299 |
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300 const size_t alignment = os::vm_page_size(); |
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301 const bool maintain_minimum = |
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302 (requested_eden_size + 2 * requested_survivor_size) <= min_gen_size(); |
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303 |
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304 // Check whether from space is below to space |
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305 if (from_start < to_start) { |
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306 // Eden, from, to |
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307 if (PrintAdaptiveSizePolicy && Verbose) { |
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308 gclog_or_tty->print_cr(" Eden, from, to:"); |
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309 } |
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310 |
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311 // Set eden |
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312 // "requested_eden_size" is a goal for the size of eden |
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313 // and may not be attainable. "eden_size" below is |
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314 // calculated based on the location of from-space and |
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315 // the goal for the size of eden. from-space is |
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316 // fixed in place because it contains live data. |
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317 // The calculation is done this way to avoid 32bit |
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318 // overflow (i.e., eden_start + requested_eden_size |
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319 // may too large for representation in 32bits). |
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320 size_t eden_size; |
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321 if (maintain_minimum) { |
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322 // Only make eden larger than the requested size if |
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323 // the minimum size of the generation has to be maintained. |
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324 // This could be done in general but policy at a higher |
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325 // level is determining a requested size for eden and that |
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326 // should be honored unless there is a fundamental reason. |
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327 eden_size = pointer_delta(from_start, |
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328 eden_start, |
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329 sizeof(char)); |
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330 } else { |
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331 eden_size = MIN2(requested_eden_size, |
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332 pointer_delta(from_start, eden_start, sizeof(char))); |
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333 } |
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334 |
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335 eden_size = align_size_down(eden_size, alignment); |
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336 eden_end = eden_start + eden_size; |
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337 assert(eden_end >= eden_start, "addition overflowed"); |
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338 |
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339 // To may resize into from space as long as it is clear of live data. |
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340 // From space must remain page aligned, though, so we need to do some |
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341 // extra calculations. |
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342 |
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343 // First calculate an optimal to-space |
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344 to_end = (char*)virtual_space()->high(); |
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345 to_start = (char*)pointer_delta(to_end, (char*)requested_survivor_size, |
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346 sizeof(char)); |
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347 |
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348 // Does the optimal to-space overlap from-space? |
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349 if (to_start < (char*)from()->end()) { |
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350 // Calculate the minimum offset possible for from_end |
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351 size_t from_size = pointer_delta(from()->top(), from_start, sizeof(char)); |
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352 |
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353 // Should we be in this method if from_space is empty? Why not the set_space method? FIX ME! |
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354 if (from_size == 0) { |
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355 from_size = alignment; |
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356 } else { |
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357 from_size = align_size_up(from_size, alignment); |
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358 } |
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359 |
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360 from_end = from_start + from_size; |
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361 assert(from_end > from_start, "addition overflow or from_size problem"); |
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362 |
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363 guarantee(from_end <= (char*)from()->end(), "from_end moved to the right"); |
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364 |
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365 // Now update to_start with the new from_end |
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366 to_start = MAX2(from_end, to_start); |
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367 } else { |
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368 // If shrinking, move to-space down to abut the end of from-space |
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369 // so that shrinking will move to-space down. If not shrinking |
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370 // to-space is moving up to allow for growth on the next expansion. |
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371 if (requested_eden_size <= cur_eden_size) { |
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372 to_start = from_end; |
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373 if (to_start + requested_survivor_size > to_start) { |
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374 to_end = to_start + requested_survivor_size; |
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375 } |
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376 } |
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377 // else leave to_end pointing to the high end of the virtual space. |
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378 } |
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379 |
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380 guarantee(to_start != to_end, "to space is zero sized"); |
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381 |
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382 if (PrintAdaptiveSizePolicy && Verbose) { |
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383 gclog_or_tty->print_cr(" [eden_start .. eden_end): " |
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384 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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385 p2i(eden_start), |
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386 p2i(eden_end), |
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387 pointer_delta(eden_end, eden_start, sizeof(char))); |
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388 gclog_or_tty->print_cr(" [from_start .. from_end): " |
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389 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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390 p2i(from_start), |
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391 p2i(from_end), |
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392 pointer_delta(from_end, from_start, sizeof(char))); |
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393 gclog_or_tty->print_cr(" [ to_start .. to_end): " |
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394 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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395 p2i(to_start), |
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396 p2i(to_end), |
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397 pointer_delta( to_end, to_start, sizeof(char))); |
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398 } |
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399 } else { |
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400 // Eden, to, from |
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401 if (PrintAdaptiveSizePolicy && Verbose) { |
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402 gclog_or_tty->print_cr(" Eden, to, from:"); |
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403 } |
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404 |
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405 // Calculate the to-space boundaries based on |
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406 // the start of from-space. |
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407 to_end = from_start; |
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408 to_start = (char*)pointer_delta(from_start, |
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409 (char*)requested_survivor_size, |
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410 sizeof(char)); |
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411 // Calculate the ideal eden boundaries. |
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412 // eden_end is already at the bottom of the generation |
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413 assert(eden_start == virtual_space()->low(), |
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414 "Eden is not starting at the low end of the virtual space"); |
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415 if (eden_start + requested_eden_size >= eden_start) { |
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416 eden_end = eden_start + requested_eden_size; |
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417 } else { |
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418 eden_end = to_start; |
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419 } |
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420 |
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421 // Does eden intrude into to-space? to-space |
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422 // gets priority but eden is not allowed to shrink |
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423 // to 0. |
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424 if (eden_end > to_start) { |
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425 eden_end = to_start; |
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426 } |
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427 |
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428 // Don't let eden shrink down to 0 or less. |
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429 eden_end = MAX2(eden_end, eden_start + alignment); |
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430 assert(eden_start + alignment >= eden_start, "Overflow"); |
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431 |
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432 size_t eden_size; |
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433 if (maintain_minimum) { |
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434 // Use all the space available. |
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435 eden_end = MAX2(eden_end, to_start); |
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436 eden_size = pointer_delta(eden_end, eden_start, sizeof(char)); |
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437 eden_size = MIN2(eden_size, cur_eden_size); |
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438 } else { |
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439 eden_size = pointer_delta(eden_end, eden_start, sizeof(char)); |
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440 } |
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441 eden_size = align_size_down(eden_size, alignment); |
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442 assert(maintain_minimum || eden_size <= requested_eden_size, |
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443 "Eden size is too large"); |
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444 assert(eden_size >= alignment, "Eden size is too small"); |
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445 eden_end = eden_start + eden_size; |
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446 |
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447 // Move to-space down to eden. |
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448 if (requested_eden_size < cur_eden_size) { |
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449 to_start = eden_end; |
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450 if (to_start + requested_survivor_size > to_start) { |
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451 to_end = MIN2(from_start, to_start + requested_survivor_size); |
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452 } else { |
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453 to_end = from_start; |
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454 } |
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455 } |
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456 |
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457 // eden_end may have moved so again make sure |
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458 // the to-space and eden don't overlap. |
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459 to_start = MAX2(eden_end, to_start); |
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460 |
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461 // from-space |
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462 size_t from_used = from()->used(); |
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463 if (requested_survivor_size > from_used) { |
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464 if (from_start + requested_survivor_size >= from_start) { |
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465 from_end = from_start + requested_survivor_size; |
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466 } |
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467 if (from_end > virtual_space()->high()) { |
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468 from_end = virtual_space()->high(); |
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469 } |
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470 } |
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471 |
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472 assert(to_start >= eden_end, "to-space should be above eden"); |
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473 if (PrintAdaptiveSizePolicy && Verbose) { |
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474 gclog_or_tty->print_cr(" [eden_start .. eden_end): " |
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475 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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476 p2i(eden_start), |
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477 p2i(eden_end), |
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478 pointer_delta(eden_end, eden_start, sizeof(char))); |
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479 gclog_or_tty->print_cr(" [ to_start .. to_end): " |
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480 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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481 p2i(to_start), |
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482 p2i(to_end), |
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483 pointer_delta( to_end, to_start, sizeof(char))); |
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484 gclog_or_tty->print_cr(" [from_start .. from_end): " |
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485 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT, |
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486 p2i(from_start), |
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487 p2i(from_end), |
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488 pointer_delta(from_end, from_start, sizeof(char))); |
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489 } |
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490 } |
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491 |
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492 |
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493 guarantee((HeapWord*)from_start <= from()->bottom(), |
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494 "from start moved to the right"); |
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495 guarantee((HeapWord*)from_end >= from()->top(), |
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496 "from end moved into live data"); |
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497 assert(is_object_aligned((intptr_t)eden_start), "checking alignment"); |
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498 assert(is_object_aligned((intptr_t)from_start), "checking alignment"); |
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499 assert(is_object_aligned((intptr_t)to_start), "checking alignment"); |
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500 |
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501 MemRegion edenMR((HeapWord*)eden_start, (HeapWord*)eden_end); |
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502 MemRegion toMR ((HeapWord*)to_start, (HeapWord*)to_end); |
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503 MemRegion fromMR((HeapWord*)from_start, (HeapWord*)from_end); |
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504 |
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505 // Let's make sure the call to initialize doesn't reset "top"! |
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506 HeapWord* old_from_top = from()->top(); |
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507 |
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508 // For PrintAdaptiveSizePolicy block below |
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509 size_t old_from = from()->capacity(); |
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510 size_t old_to = to()->capacity(); |
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511 |
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512 // If not clearing the spaces, do some checking to verify that |
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513 // the spaces are already mangled. |
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514 |
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515 // Must check mangling before the spaces are reshaped. Otherwise, |
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516 // the bottom or end of one space may have moved into another |
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517 // a failure of the check may not correctly indicate which space |
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518 // is not properly mangled. |
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519 if (ZapUnusedHeapArea) { |
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520 HeapWord* limit = (HeapWord*) virtual_space()->high(); |
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521 eden()->check_mangled_unused_area(limit); |
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522 from()->check_mangled_unused_area(limit); |
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523 to()->check_mangled_unused_area(limit); |
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524 } |
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525 |
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526 // The call to initialize NULL's the next compaction space |
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527 eden()->initialize(edenMR, |
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528 SpaceDecorator::Clear, |
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529 SpaceDecorator::DontMangle); |
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530 eden()->set_next_compaction_space(from()); |
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531 to()->initialize(toMR , |
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532 SpaceDecorator::Clear, |
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533 SpaceDecorator::DontMangle); |
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534 from()->initialize(fromMR, |
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535 SpaceDecorator::DontClear, |
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536 SpaceDecorator::DontMangle); |
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537 |
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538 assert(from()->top() == old_from_top, "from top changed!"); |
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539 |
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540 if (PrintAdaptiveSizePolicy) { |
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541 GenCollectedHeap* gch = GenCollectedHeap::heap(); |
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542 assert(gch->kind() == CollectedHeap::GenCollectedHeap, "Sanity"); |
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543 |
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544 gclog_or_tty->print("AdaptiveSizePolicy::survivor space sizes: " |
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545 "collection: %d " |
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546 "(" SIZE_FORMAT ", " SIZE_FORMAT ") -> " |
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547 "(" SIZE_FORMAT ", " SIZE_FORMAT ") ", |
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548 gch->total_collections(), |
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549 old_from, old_to, |
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550 from()->capacity(), |
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551 to()->capacity()); |
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552 gclog_or_tty->cr(); |
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553 } |
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554 } |
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555 |
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556 void ASParNewGeneration::compute_new_size() { |
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557 GenCollectedHeap* gch = GenCollectedHeap::heap(); |
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558 assert(gch->kind() == CollectedHeap::GenCollectedHeap, |
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559 "not a CMS generational heap"); |
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560 |
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561 |
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562 CMSAdaptiveSizePolicy* size_policy = |
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563 (CMSAdaptiveSizePolicy*)gch->gen_policy()->size_policy(); |
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564 assert(size_policy->is_gc_cms_adaptive_size_policy(), |
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565 "Wrong type of size policy"); |
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566 |
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567 size_t survived = from()->used(); |
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568 if (!survivor_overflow()) { |
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569 // Keep running averages on how much survived |
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570 size_policy->avg_survived()->sample(survived); |
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571 } else { |
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572 size_t promoted = |
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573 (size_t) next_gen()->gc_stats()->avg_promoted()->last_sample(); |
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574 assert(promoted < gch->capacity(), "Conversion problem?"); |
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575 size_t survived_guess = survived + promoted; |
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576 size_policy->avg_survived()->sample(survived_guess); |
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577 } |
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578 |
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579 size_t survivor_limit = max_survivor_size(); |
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580 _tenuring_threshold = |
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581 size_policy->compute_survivor_space_size_and_threshold( |
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582 _survivor_overflow, |
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583 _tenuring_threshold, |
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584 survivor_limit); |
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585 size_policy->avg_young_live()->sample(used()); |
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586 size_policy->avg_eden_live()->sample(eden()->used()); |
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587 |
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588 size_policy->compute_eden_space_size(eden()->capacity(), max_gen_size()); |
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589 |
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590 resize(size_policy->calculated_eden_size_in_bytes(), |
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591 size_policy->calculated_survivor_size_in_bytes()); |
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592 |
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593 if (UsePerfData) { |
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594 CMSGCAdaptivePolicyCounters* counters = |
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595 (CMSGCAdaptivePolicyCounters*) gch->collector_policy()->counters(); |
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596 assert(counters->kind() == |
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597 GCPolicyCounters::CMSGCAdaptivePolicyCountersKind, |
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598 "Wrong kind of counters"); |
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599 counters->update_tenuring_threshold(_tenuring_threshold); |
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600 counters->update_survivor_overflowed(_survivor_overflow); |
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601 counters->update_young_capacity(capacity()); |
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602 } |
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603 } |
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604 |
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605 |
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606 #ifndef PRODUCT |
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607 // Changes from PSYoungGen version |
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608 // value of "alignment" |
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609 void ASParNewGeneration::space_invariants() { |
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610 const size_t alignment = os::vm_page_size(); |
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611 |
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612 // Currently, our eden size cannot shrink to zero |
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613 guarantee(eden()->capacity() >= alignment, "eden too small"); |
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614 guarantee(from()->capacity() >= alignment, "from too small"); |
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615 guarantee(to()->capacity() >= alignment, "to too small"); |
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616 |
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617 // Relationship of spaces to each other |
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618 char* eden_start = (char*)eden()->bottom(); |
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619 char* eden_end = (char*)eden()->end(); |
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620 char* from_start = (char*)from()->bottom(); |
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621 char* from_end = (char*)from()->end(); |
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622 char* to_start = (char*)to()->bottom(); |
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623 char* to_end = (char*)to()->end(); |
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624 |
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625 guarantee(eden_start >= virtual_space()->low(), "eden bottom"); |
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626 guarantee(eden_start < eden_end, "eden space consistency"); |
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627 guarantee(from_start < from_end, "from space consistency"); |
|
628 guarantee(to_start < to_end, "to space consistency"); |
|
629 |
|
630 // Check whether from space is below to space |
|
631 if (from_start < to_start) { |
|
632 // Eden, from, to |
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633 guarantee(eden_end <= from_start, "eden/from boundary"); |
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634 guarantee(from_end <= to_start, "from/to boundary"); |
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635 guarantee(to_end <= virtual_space()->high(), "to end"); |
|
636 } else { |
|
637 // Eden, to, from |
|
638 guarantee(eden_end <= to_start, "eden/to boundary"); |
|
639 guarantee(to_end <= from_start, "to/from boundary"); |
|
640 guarantee(from_end <= virtual_space()->high(), "from end"); |
|
641 } |
|
642 |
|
643 // More checks that the virtual space is consistent with the spaces |
|
644 assert(virtual_space()->committed_size() >= |
|
645 (eden()->capacity() + |
|
646 to()->capacity() + |
|
647 from()->capacity()), "Committed size is inconsistent"); |
|
648 assert(virtual_space()->committed_size() <= virtual_space()->reserved_size(), |
|
649 "Space invariant"); |
|
650 char* eden_top = (char*)eden()->top(); |
|
651 char* from_top = (char*)from()->top(); |
|
652 char* to_top = (char*)to()->top(); |
|
653 assert(eden_top <= virtual_space()->high(), "eden top"); |
|
654 assert(from_top <= virtual_space()->high(), "from top"); |
|
655 assert(to_top <= virtual_space()->high(), "to top"); |
|
656 } |
|
657 #endif |
|