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1 /* |
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2 * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates. |
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3 * |
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4 * This code is free software; you can redistribute it and/or modify it |
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5 * under the terms of the GNU General Public License version 2 only, as |
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6 * published by the Free Software Foundation. |
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7 * |
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8 * This code is distributed in the hope that it will be useful, but WITHOUT |
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9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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11 * version 2 for more details (a copy is included in the LICENSE file that |
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12 * accompanied this code). |
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13 * |
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14 * You should have received a copy of the GNU General Public License version |
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15 * 2 along with this work; if not, write to the Free Software Foundation, |
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16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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17 * |
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18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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19 * or visit www.oracle.com if you need additional information or have any |
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20 * questions. |
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21 * |
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22 */ |
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23 |
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24 #include "precompiled.hpp" |
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25 #include "oops/oop.hpp" |
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26 #include "oops/oop.inline.hpp" |
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27 #include "gc/epsilon/epsilonCollectedHeap.hpp" |
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28 |
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29 jint EpsilonCollectedHeap::initialize() { |
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30 CollectedHeap::pre_initialize(); |
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31 |
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32 size_t init_byte_size = _policy->initial_heap_byte_size(); |
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33 size_t max_byte_size = _policy->max_heap_byte_size(); |
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34 size_t align = _policy->heap_alignment(); |
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35 |
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36 ReservedSpace heap_rs = Universe::reserve_heap(max_byte_size, align); |
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37 _virtual_space.initialize(heap_rs, init_byte_size); |
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38 |
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39 MemRegion committed_region((HeapWord*)_virtual_space.low(), (HeapWord*)_virtual_space.high()); |
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40 MemRegion reserved_region((HeapWord*)_virtual_space.low_boundary(), (HeapWord*)_virtual_space.high_boundary()); |
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41 |
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42 initialize_reserved_region(reserved_region.start(), reserved_region.end()); |
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43 |
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44 _space = new ContiguousSpace(); |
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45 _space->initialize(committed_region, true, true); |
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46 |
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47 EpsilonBarrierSet* bs = new EpsilonBarrierSet(); |
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48 set_barrier_set(bs); |
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49 |
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50 _max_tlab_size = MIN2(CollectedHeap::max_tlab_size(), EpsilonMaxTLABSize / HeapWordSize); |
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51 |
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52 _monitoring_support = new EpsilonMonitoringSupport(this); |
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53 _last_counter_update = 0; |
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54 |
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55 if (init_byte_size != max_byte_size) { |
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56 log_info(gc)("Initialized with " SIZE_FORMAT "M heap, resizeable to up to " SIZE_FORMAT "M heap with " SIZE_FORMAT "M steps", |
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57 init_byte_size / M, max_byte_size / M, EpsilonMinHeapExpand / M); |
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58 } else { |
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59 log_info(gc)("Initialized with " SIZE_FORMAT "M non-resizeable heap", init_byte_size / M); |
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60 } |
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61 if (UseTLAB) { |
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62 log_info(gc)("Using TLAB allocation; min: " SIZE_FORMAT "K, max: " SIZE_FORMAT "K", |
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63 ThreadLocalAllocBuffer::min_size()*HeapWordSize / K, |
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64 _max_tlab_size*HeapWordSize / K); |
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65 } else { |
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66 log_info(gc)("Not using TLAB allocation"); |
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67 } |
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68 |
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69 return JNI_OK; |
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70 } |
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71 |
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72 size_t EpsilonCollectedHeap::unsafe_max_tlab_alloc(Thread *thr) const { |
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73 // This is the only way we can control TLAB sizes without having safepoints. |
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74 // Implement exponential expansion within [MinTLABSize; _max_tlab_size], based |
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75 // on previously "used" TLAB size. |
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76 |
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77 size_t size = MIN2(_max_tlab_size * HeapWordSize, MAX2(MinTLABSize, thr->tlab().used() * HeapWordSize * 2)); |
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78 |
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79 if (log_is_enabled(Trace, gc)) { |
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80 ResourceMark rm; |
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81 log_trace(gc)( |
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82 "Selecting TLAB size for \"%s\" (Desired: " SIZE_FORMAT "K, Used: " SIZE_FORMAT "K) -> " SIZE_FORMAT "K", |
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83 Thread::current()->name(), |
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84 thr->tlab().desired_size() * HeapWordSize / K, |
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85 thr->tlab().used() * HeapWordSize / K, |
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86 size / K); |
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87 } |
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88 |
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89 return size; |
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90 } |
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91 |
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92 EpsilonCollectedHeap* EpsilonCollectedHeap::heap() { |
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93 CollectedHeap* heap = Universe::heap(); |
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94 assert(heap != NULL, "Uninitialized access to EpsilonCollectedHeap::heap()"); |
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95 assert(heap->kind() == CollectedHeap::EpsilonCollectedHeap, "Not a EpsilonCollectedHeap"); |
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96 return (EpsilonCollectedHeap*)heap; |
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97 } |
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98 |
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99 HeapWord* EpsilonCollectedHeap::allocate_work(size_t size) { |
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100 HeapWord* res = _space->par_allocate(size); |
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101 |
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102 while (res == NULL) { |
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103 // Allocation failed, attempt expansion, and retry: |
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104 MutexLockerEx ml(Heap_lock); |
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105 if (!_virtual_space.expand_by(MAX2(size, EpsilonMinHeapExpand))) { |
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106 return NULL; |
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107 } |
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108 _space->set_end((HeapWord *) _virtual_space.high()); |
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109 res = _space->par_allocate(size); |
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110 } |
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111 |
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112 size_t used = _space->used(); |
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113 if (used - _last_counter_update >= 1024 * 1024) { |
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114 _last_counter_update = used; |
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115 _monitoring_support->update_counters(); |
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116 } |
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117 return res; |
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118 } |
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119 |
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120 HeapWord* EpsilonCollectedHeap::allocate_new_tlab(size_t size) { |
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121 return allocate_work(size); |
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122 } |
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123 |
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124 HeapWord* EpsilonCollectedHeap::mem_allocate(size_t size, bool *gc_overhead_limit_was_exceeded) { |
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125 *gc_overhead_limit_was_exceeded = false; |
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126 return allocate_work(size); |
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127 } |
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128 |
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129 void EpsilonCollectedHeap::collect(GCCause::Cause cause) { |
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130 log_info(gc)("GC was triggered with cause \"%s\". Ignoring.", GCCause::to_string(cause)); |
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131 _monitoring_support->update_counters(); |
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132 } |
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133 |
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134 void EpsilonCollectedHeap::do_full_collection(bool clear_all_soft_refs) { |
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135 log_info(gc)("Full GC was triggered with cause \"%s\". Ignoring.", GCCause::to_string(gc_cause())); |
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136 _monitoring_support->update_counters(); |
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137 } |
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138 |
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139 void EpsilonCollectedHeap::safe_object_iterate(ObjectClosure *cl) { |
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140 _space->safe_object_iterate(cl); |
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141 } |
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142 |
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143 void EpsilonCollectedHeap::print_on(outputStream *st) const { |
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144 st->print_cr("Epsilon Heap"); |
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145 |
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146 // Cast away constness: |
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147 ((VirtualSpace)_virtual_space).print_on(st); |
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148 |
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149 st->print_cr("Allocation space:"); |
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150 _space->print_on(st); |
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151 } |
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152 |
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153 void EpsilonCollectedHeap::print_tracing_info() const { |
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154 Log(gc) log; |
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155 size_t allocated_kb = used() / K; |
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156 log.info("Total allocated: " SIZE_FORMAT " KB", |
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157 allocated_kb); |
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158 log.info("Average allocation rate: " SIZE_FORMAT " KB/sec", |
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159 allocated_kb * NANOSECS_PER_SEC / os::elapsed_counter()); |
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160 } |