Tue, 18 Sep 2012 14:15:06 -0700
7197557: NPG: nsk/sysdict/vm/stress/chain/chain004 hangs intermittently
Reviewed-by: johnc, ysr
duke@435 | 1 | /* |
coleenp@4037 | 2 | * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "gc_implementation/shared/adaptiveSizePolicy.hpp" |
stefank@2314 | 27 | #include "gc_implementation/shared/gcPolicyCounters.hpp" |
stefank@2314 | 28 | #include "gc_implementation/shared/vmGCOperations.hpp" |
stefank@2314 | 29 | #include "memory/cardTableRS.hpp" |
stefank@2314 | 30 | #include "memory/collectorPolicy.hpp" |
stefank@2314 | 31 | #include "memory/gcLocker.inline.hpp" |
stefank@2314 | 32 | #include "memory/genCollectedHeap.hpp" |
stefank@2314 | 33 | #include "memory/generationSpec.hpp" |
stefank@2314 | 34 | #include "memory/space.hpp" |
stefank@2314 | 35 | #include "memory/universe.hpp" |
stefank@2314 | 36 | #include "runtime/arguments.hpp" |
stefank@2314 | 37 | #include "runtime/globals_extension.hpp" |
stefank@2314 | 38 | #include "runtime/handles.inline.hpp" |
stefank@2314 | 39 | #include "runtime/java.hpp" |
stefank@2314 | 40 | #include "runtime/vmThread.hpp" |
stefank@2314 | 41 | #ifdef TARGET_OS_FAMILY_linux |
stefank@2314 | 42 | # include "thread_linux.inline.hpp" |
stefank@2314 | 43 | #endif |
stefank@2314 | 44 | #ifdef TARGET_OS_FAMILY_solaris |
stefank@2314 | 45 | # include "thread_solaris.inline.hpp" |
stefank@2314 | 46 | #endif |
stefank@2314 | 47 | #ifdef TARGET_OS_FAMILY_windows |
stefank@2314 | 48 | # include "thread_windows.inline.hpp" |
stefank@2314 | 49 | #endif |
never@3156 | 50 | #ifdef TARGET_OS_FAMILY_bsd |
never@3156 | 51 | # include "thread_bsd.inline.hpp" |
never@3156 | 52 | #endif |
stefank@2314 | 53 | #ifndef SERIALGC |
stefank@2314 | 54 | #include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp" |
stefank@2314 | 55 | #include "gc_implementation/concurrentMarkSweep/cmsGCAdaptivePolicyCounters.hpp" |
stefank@2314 | 56 | #endif |
duke@435 | 57 | |
duke@435 | 58 | // CollectorPolicy methods. |
duke@435 | 59 | |
duke@435 | 60 | void CollectorPolicy::initialize_flags() { |
coleenp@4037 | 61 | if (MetaspaceSize > MaxMetaspaceSize) { |
coleenp@4037 | 62 | MaxMetaspaceSize = MetaspaceSize; |
duke@435 | 63 | } |
coleenp@4037 | 64 | MetaspaceSize = MAX2(min_alignment(), align_size_down_(MetaspaceSize, min_alignment())); |
coleenp@4037 | 65 | // Don't increase Metaspace size limit above specified. |
coleenp@4037 | 66 | MaxMetaspaceSize = align_size_down(MaxMetaspaceSize, max_alignment()); |
coleenp@4037 | 67 | if (MetaspaceSize > MaxMetaspaceSize) { |
coleenp@4037 | 68 | MetaspaceSize = MaxMetaspaceSize; |
kvn@2150 | 69 | } |
duke@435 | 70 | |
coleenp@4037 | 71 | MinMetaspaceExpansion = MAX2(min_alignment(), align_size_down_(MinMetaspaceExpansion, min_alignment())); |
coleenp@4037 | 72 | MaxMetaspaceExpansion = MAX2(min_alignment(), align_size_down_(MaxMetaspaceExpansion, min_alignment())); |
duke@435 | 73 | |
duke@435 | 74 | MinHeapDeltaBytes = align_size_up(MinHeapDeltaBytes, min_alignment()); |
duke@435 | 75 | |
coleenp@4037 | 76 | assert(MetaspaceSize % min_alignment() == 0, "metapace alignment"); |
coleenp@4037 | 77 | assert(MaxMetaspaceSize % max_alignment() == 0, "maximum metaspace alignment"); |
coleenp@4037 | 78 | if (MetaspaceSize < 256*K) { |
coleenp@4037 | 79 | vm_exit_during_initialization("Too small initial Metaspace size"); |
duke@435 | 80 | } |
duke@435 | 81 | } |
duke@435 | 82 | |
duke@435 | 83 | void CollectorPolicy::initialize_size_info() { |
duke@435 | 84 | // User inputs from -mx and ms are aligned |
phh@1499 | 85 | set_initial_heap_byte_size(InitialHeapSize); |
jmasa@448 | 86 | if (initial_heap_byte_size() == 0) { |
jmasa@448 | 87 | set_initial_heap_byte_size(NewSize + OldSize); |
duke@435 | 88 | } |
ysr@777 | 89 | set_initial_heap_byte_size(align_size_up(_initial_heap_byte_size, |
ysr@777 | 90 | min_alignment())); |
ysr@777 | 91 | |
ysr@777 | 92 | set_min_heap_byte_size(Arguments::min_heap_size()); |
jmasa@448 | 93 | if (min_heap_byte_size() == 0) { |
jmasa@448 | 94 | set_min_heap_byte_size(NewSize + OldSize); |
duke@435 | 95 | } |
ysr@777 | 96 | set_min_heap_byte_size(align_size_up(_min_heap_byte_size, |
ysr@777 | 97 | min_alignment())); |
ysr@777 | 98 | |
ysr@777 | 99 | set_max_heap_byte_size(align_size_up(MaxHeapSize, max_alignment())); |
duke@435 | 100 | |
duke@435 | 101 | // Check heap parameter properties |
jmasa@448 | 102 | if (initial_heap_byte_size() < M) { |
duke@435 | 103 | vm_exit_during_initialization("Too small initial heap"); |
duke@435 | 104 | } |
duke@435 | 105 | // Check heap parameter properties |
jmasa@448 | 106 | if (min_heap_byte_size() < M) { |
duke@435 | 107 | vm_exit_during_initialization("Too small minimum heap"); |
duke@435 | 108 | } |
jmasa@448 | 109 | if (initial_heap_byte_size() <= NewSize) { |
duke@435 | 110 | // make sure there is at least some room in old space |
duke@435 | 111 | vm_exit_during_initialization("Too small initial heap for new size specified"); |
duke@435 | 112 | } |
jmasa@448 | 113 | if (max_heap_byte_size() < min_heap_byte_size()) { |
duke@435 | 114 | vm_exit_during_initialization("Incompatible minimum and maximum heap sizes specified"); |
duke@435 | 115 | } |
jmasa@448 | 116 | if (initial_heap_byte_size() < min_heap_byte_size()) { |
duke@435 | 117 | vm_exit_during_initialization("Incompatible minimum and initial heap sizes specified"); |
duke@435 | 118 | } |
jmasa@448 | 119 | if (max_heap_byte_size() < initial_heap_byte_size()) { |
duke@435 | 120 | vm_exit_during_initialization("Incompatible initial and maximum heap sizes specified"); |
duke@435 | 121 | } |
jmasa@448 | 122 | |
jmasa@448 | 123 | if (PrintGCDetails && Verbose) { |
jmasa@448 | 124 | gclog_or_tty->print_cr("Minimum heap " SIZE_FORMAT " Initial heap " |
jmasa@448 | 125 | SIZE_FORMAT " Maximum heap " SIZE_FORMAT, |
jmasa@448 | 126 | min_heap_byte_size(), initial_heap_byte_size(), max_heap_byte_size()); |
jmasa@448 | 127 | } |
duke@435 | 128 | } |
duke@435 | 129 | |
jmasa@1822 | 130 | bool CollectorPolicy::use_should_clear_all_soft_refs(bool v) { |
jmasa@1822 | 131 | bool result = _should_clear_all_soft_refs; |
jmasa@1822 | 132 | set_should_clear_all_soft_refs(false); |
jmasa@1822 | 133 | return result; |
jmasa@1822 | 134 | } |
duke@435 | 135 | |
duke@435 | 136 | GenRemSet* CollectorPolicy::create_rem_set(MemRegion whole_heap, |
duke@435 | 137 | int max_covered_regions) { |
duke@435 | 138 | switch (rem_set_name()) { |
duke@435 | 139 | case GenRemSet::CardTable: { |
duke@435 | 140 | CardTableRS* res = new CardTableRS(whole_heap, max_covered_regions); |
duke@435 | 141 | return res; |
duke@435 | 142 | } |
duke@435 | 143 | default: |
duke@435 | 144 | guarantee(false, "unrecognized GenRemSet::Name"); |
duke@435 | 145 | return NULL; |
duke@435 | 146 | } |
duke@435 | 147 | } |
duke@435 | 148 | |
jmasa@1822 | 149 | void CollectorPolicy::cleared_all_soft_refs() { |
jmasa@1822 | 150 | // If near gc overhear limit, continue to clear SoftRefs. SoftRefs may |
jmasa@1822 | 151 | // have been cleared in the last collection but if the gc overhear |
jmasa@1822 | 152 | // limit continues to be near, SoftRefs should still be cleared. |
jmasa@1822 | 153 | if (size_policy() != NULL) { |
jmasa@1822 | 154 | _should_clear_all_soft_refs = size_policy()->gc_overhead_limit_near(); |
jmasa@1822 | 155 | } |
jmasa@1822 | 156 | _all_soft_refs_clear = true; |
jmasa@1822 | 157 | } |
jmasa@1822 | 158 | |
jmasa@1822 | 159 | |
duke@435 | 160 | // GenCollectorPolicy methods. |
duke@435 | 161 | |
jmasa@448 | 162 | size_t GenCollectorPolicy::scale_by_NewRatio_aligned(size_t base_size) { |
jmasa@448 | 163 | size_t x = base_size / (NewRatio+1); |
jmasa@448 | 164 | size_t new_gen_size = x > min_alignment() ? |
jmasa@448 | 165 | align_size_down(x, min_alignment()) : |
jmasa@448 | 166 | min_alignment(); |
jmasa@448 | 167 | return new_gen_size; |
jmasa@448 | 168 | } |
jmasa@448 | 169 | |
jmasa@448 | 170 | size_t GenCollectorPolicy::bound_minus_alignment(size_t desired_size, |
jmasa@448 | 171 | size_t maximum_size) { |
jmasa@448 | 172 | size_t alignment = min_alignment(); |
jmasa@448 | 173 | size_t max_minus = maximum_size - alignment; |
jmasa@448 | 174 | return desired_size < max_minus ? desired_size : max_minus; |
jmasa@448 | 175 | } |
jmasa@448 | 176 | |
jmasa@448 | 177 | |
duke@435 | 178 | void GenCollectorPolicy::initialize_size_policy(size_t init_eden_size, |
duke@435 | 179 | size_t init_promo_size, |
duke@435 | 180 | size_t init_survivor_size) { |
jmasa@448 | 181 | const double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0; |
duke@435 | 182 | _size_policy = new AdaptiveSizePolicy(init_eden_size, |
duke@435 | 183 | init_promo_size, |
duke@435 | 184 | init_survivor_size, |
duke@435 | 185 | max_gc_minor_pause_sec, |
duke@435 | 186 | GCTimeRatio); |
duke@435 | 187 | } |
duke@435 | 188 | |
duke@435 | 189 | size_t GenCollectorPolicy::compute_max_alignment() { |
duke@435 | 190 | // The card marking array and the offset arrays for old generations are |
duke@435 | 191 | // committed in os pages as well. Make sure they are entirely full (to |
duke@435 | 192 | // avoid partial page problems), e.g. if 512 bytes heap corresponds to 1 |
duke@435 | 193 | // byte entry and the os page size is 4096, the maximum heap size should |
duke@435 | 194 | // be 512*4096 = 2MB aligned. |
duke@435 | 195 | size_t alignment = GenRemSet::max_alignment_constraint(rem_set_name()); |
duke@435 | 196 | |
duke@435 | 197 | // Parallel GC does its own alignment of the generations to avoid requiring a |
duke@435 | 198 | // large page (256M on some platforms) for the permanent generation. The |
duke@435 | 199 | // other collectors should also be updated to do their own alignment and then |
duke@435 | 200 | // this use of lcm() should be removed. |
duke@435 | 201 | if (UseLargePages && !UseParallelGC) { |
duke@435 | 202 | // in presence of large pages we have to make sure that our |
duke@435 | 203 | // alignment is large page aware |
duke@435 | 204 | alignment = lcm(os::large_page_size(), alignment); |
duke@435 | 205 | } |
duke@435 | 206 | |
duke@435 | 207 | return alignment; |
duke@435 | 208 | } |
duke@435 | 209 | |
duke@435 | 210 | void GenCollectorPolicy::initialize_flags() { |
duke@435 | 211 | // All sizes must be multiples of the generation granularity. |
duke@435 | 212 | set_min_alignment((uintx) Generation::GenGrain); |
duke@435 | 213 | set_max_alignment(compute_max_alignment()); |
duke@435 | 214 | assert(max_alignment() >= min_alignment() && |
duke@435 | 215 | max_alignment() % min_alignment() == 0, |
duke@435 | 216 | "invalid alignment constraints"); |
duke@435 | 217 | |
duke@435 | 218 | CollectorPolicy::initialize_flags(); |
duke@435 | 219 | |
duke@435 | 220 | // All generational heaps have a youngest gen; handle those flags here. |
duke@435 | 221 | |
duke@435 | 222 | // Adjust max size parameters |
duke@435 | 223 | if (NewSize > MaxNewSize) { |
duke@435 | 224 | MaxNewSize = NewSize; |
duke@435 | 225 | } |
duke@435 | 226 | NewSize = align_size_down(NewSize, min_alignment()); |
duke@435 | 227 | MaxNewSize = align_size_down(MaxNewSize, min_alignment()); |
duke@435 | 228 | |
duke@435 | 229 | // Check validity of heap flags |
duke@435 | 230 | assert(NewSize % min_alignment() == 0, "eden space alignment"); |
duke@435 | 231 | assert(MaxNewSize % min_alignment() == 0, "survivor space alignment"); |
duke@435 | 232 | |
duke@435 | 233 | if (NewSize < 3*min_alignment()) { |
duke@435 | 234 | // make sure there room for eden and two survivor spaces |
duke@435 | 235 | vm_exit_during_initialization("Too small new size specified"); |
duke@435 | 236 | } |
duke@435 | 237 | if (SurvivorRatio < 1 || NewRatio < 1) { |
duke@435 | 238 | vm_exit_during_initialization("Invalid heap ratio specified"); |
duke@435 | 239 | } |
duke@435 | 240 | } |
duke@435 | 241 | |
duke@435 | 242 | void TwoGenerationCollectorPolicy::initialize_flags() { |
duke@435 | 243 | GenCollectorPolicy::initialize_flags(); |
duke@435 | 244 | |
duke@435 | 245 | OldSize = align_size_down(OldSize, min_alignment()); |
duke@435 | 246 | if (NewSize + OldSize > MaxHeapSize) { |
duke@435 | 247 | MaxHeapSize = NewSize + OldSize; |
duke@435 | 248 | } |
duke@435 | 249 | MaxHeapSize = align_size_up(MaxHeapSize, max_alignment()); |
duke@435 | 250 | |
duke@435 | 251 | always_do_update_barrier = UseConcMarkSweepGC; |
duke@435 | 252 | |
duke@435 | 253 | // Check validity of heap flags |
duke@435 | 254 | assert(OldSize % min_alignment() == 0, "old space alignment"); |
duke@435 | 255 | assert(MaxHeapSize % max_alignment() == 0, "maximum heap alignment"); |
duke@435 | 256 | } |
duke@435 | 257 | |
jmasa@448 | 258 | // Values set on the command line win over any ergonomically |
jmasa@448 | 259 | // set command line parameters. |
jmasa@448 | 260 | // Ergonomic choice of parameters are done before this |
jmasa@448 | 261 | // method is called. Values for command line parameters such as NewSize |
jmasa@448 | 262 | // and MaxNewSize feed those ergonomic choices into this method. |
jmasa@448 | 263 | // This method makes the final generation sizings consistent with |
jmasa@448 | 264 | // themselves and with overall heap sizings. |
jmasa@448 | 265 | // In the absence of explicitly set command line flags, policies |
jmasa@448 | 266 | // such as the use of NewRatio are used to size the generation. |
duke@435 | 267 | void GenCollectorPolicy::initialize_size_info() { |
duke@435 | 268 | CollectorPolicy::initialize_size_info(); |
duke@435 | 269 | |
jmasa@448 | 270 | // min_alignment() is used for alignment within a generation. |
jmasa@448 | 271 | // There is additional alignment done down stream for some |
jmasa@448 | 272 | // collectors that sometimes causes unwanted rounding up of |
jmasa@448 | 273 | // generations sizes. |
jmasa@448 | 274 | |
jmasa@448 | 275 | // Determine maximum size of gen0 |
jmasa@448 | 276 | |
jmasa@448 | 277 | size_t max_new_size = 0; |
ysr@2650 | 278 | if (FLAG_IS_CMDLINE(MaxNewSize) || FLAG_IS_ERGO(MaxNewSize)) { |
jmasa@448 | 279 | if (MaxNewSize < min_alignment()) { |
jmasa@448 | 280 | max_new_size = min_alignment(); |
ysr@2650 | 281 | } |
ysr@2650 | 282 | if (MaxNewSize >= max_heap_byte_size()) { |
jmasa@448 | 283 | max_new_size = align_size_down(max_heap_byte_size() - min_alignment(), |
jmasa@448 | 284 | min_alignment()); |
jmasa@448 | 285 | warning("MaxNewSize (" SIZE_FORMAT "k) is equal to or " |
jmasa@448 | 286 | "greater than the entire heap (" SIZE_FORMAT "k). A " |
jmasa@448 | 287 | "new generation size of " SIZE_FORMAT "k will be used.", |
jmasa@448 | 288 | MaxNewSize/K, max_heap_byte_size()/K, max_new_size/K); |
jmasa@448 | 289 | } else { |
jmasa@448 | 290 | max_new_size = align_size_down(MaxNewSize, min_alignment()); |
jmasa@448 | 291 | } |
jmasa@448 | 292 | |
jmasa@448 | 293 | // The case for FLAG_IS_ERGO(MaxNewSize) could be treated |
jmasa@448 | 294 | // specially at this point to just use an ergonomically set |
jmasa@448 | 295 | // MaxNewSize to set max_new_size. For cases with small |
jmasa@448 | 296 | // heaps such a policy often did not work because the MaxNewSize |
jmasa@448 | 297 | // was larger than the entire heap. The interpretation given |
jmasa@448 | 298 | // to ergonomically set flags is that the flags are set |
jmasa@448 | 299 | // by different collectors for their own special needs but |
jmasa@448 | 300 | // are not allowed to badly shape the heap. This allows the |
jmasa@448 | 301 | // different collectors to decide what's best for themselves |
jmasa@448 | 302 | // without having to factor in the overall heap shape. It |
jmasa@448 | 303 | // can be the case in the future that the collectors would |
jmasa@448 | 304 | // only make "wise" ergonomics choices and this policy could |
jmasa@448 | 305 | // just accept those choices. The choices currently made are |
jmasa@448 | 306 | // not always "wise". |
duke@435 | 307 | } else { |
jmasa@448 | 308 | max_new_size = scale_by_NewRatio_aligned(max_heap_byte_size()); |
jmasa@448 | 309 | // Bound the maximum size by NewSize below (since it historically |
duke@435 | 310 | // would have been NewSize and because the NewRatio calculation could |
duke@435 | 311 | // yield a size that is too small) and bound it by MaxNewSize above. |
jmasa@448 | 312 | // Ergonomics plays here by previously calculating the desired |
jmasa@448 | 313 | // NewSize and MaxNewSize. |
jmasa@448 | 314 | max_new_size = MIN2(MAX2(max_new_size, NewSize), MaxNewSize); |
jmasa@448 | 315 | } |
jmasa@448 | 316 | assert(max_new_size > 0, "All paths should set max_new_size"); |
jmasa@448 | 317 | |
jmasa@448 | 318 | // Given the maximum gen0 size, determine the initial and |
ysr@2650 | 319 | // minimum gen0 sizes. |
jmasa@448 | 320 | |
jmasa@448 | 321 | if (max_heap_byte_size() == min_heap_byte_size()) { |
jmasa@448 | 322 | // The maximum and minimum heap sizes are the same so |
jmasa@448 | 323 | // the generations minimum and initial must be the |
jmasa@448 | 324 | // same as its maximum. |
jmasa@448 | 325 | set_min_gen0_size(max_new_size); |
jmasa@448 | 326 | set_initial_gen0_size(max_new_size); |
jmasa@448 | 327 | set_max_gen0_size(max_new_size); |
jmasa@448 | 328 | } else { |
jmasa@448 | 329 | size_t desired_new_size = 0; |
jmasa@448 | 330 | if (!FLAG_IS_DEFAULT(NewSize)) { |
jmasa@448 | 331 | // If NewSize is set ergonomically (for example by cms), it |
jmasa@448 | 332 | // would make sense to use it. If it is used, also use it |
jmasa@448 | 333 | // to set the initial size. Although there is no reason |
jmasa@448 | 334 | // the minimum size and the initial size have to be the same, |
jmasa@448 | 335 | // the current implementation gets into trouble during the calculation |
jmasa@448 | 336 | // of the tenured generation sizes if they are different. |
jmasa@448 | 337 | // Note that this makes the initial size and the minimum size |
jmasa@448 | 338 | // generally small compared to the NewRatio calculation. |
jmasa@448 | 339 | _min_gen0_size = NewSize; |
jmasa@448 | 340 | desired_new_size = NewSize; |
jmasa@448 | 341 | max_new_size = MAX2(max_new_size, NewSize); |
jmasa@448 | 342 | } else { |
jmasa@448 | 343 | // For the case where NewSize is the default, use NewRatio |
jmasa@448 | 344 | // to size the minimum and initial generation sizes. |
jmasa@448 | 345 | // Use the default NewSize as the floor for these values. If |
jmasa@448 | 346 | // NewRatio is overly large, the resulting sizes can be too |
jmasa@448 | 347 | // small. |
jmasa@448 | 348 | _min_gen0_size = MAX2(scale_by_NewRatio_aligned(min_heap_byte_size()), |
jmasa@448 | 349 | NewSize); |
jmasa@448 | 350 | desired_new_size = |
jmasa@448 | 351 | MAX2(scale_by_NewRatio_aligned(initial_heap_byte_size()), |
jmasa@448 | 352 | NewSize); |
jmasa@448 | 353 | } |
jmasa@448 | 354 | |
jmasa@448 | 355 | assert(_min_gen0_size > 0, "Sanity check"); |
jmasa@448 | 356 | set_initial_gen0_size(desired_new_size); |
jmasa@448 | 357 | set_max_gen0_size(max_new_size); |
jmasa@448 | 358 | |
jmasa@448 | 359 | // At this point the desirable initial and minimum sizes have been |
jmasa@448 | 360 | // determined without regard to the maximum sizes. |
jmasa@448 | 361 | |
jmasa@448 | 362 | // Bound the sizes by the corresponding overall heap sizes. |
jmasa@448 | 363 | set_min_gen0_size( |
jmasa@448 | 364 | bound_minus_alignment(_min_gen0_size, min_heap_byte_size())); |
jmasa@448 | 365 | set_initial_gen0_size( |
jmasa@448 | 366 | bound_minus_alignment(_initial_gen0_size, initial_heap_byte_size())); |
jmasa@448 | 367 | set_max_gen0_size( |
jmasa@448 | 368 | bound_minus_alignment(_max_gen0_size, max_heap_byte_size())); |
jmasa@448 | 369 | |
jmasa@448 | 370 | // At this point all three sizes have been checked against the |
jmasa@448 | 371 | // maximum sizes but have not been checked for consistency |
ysr@777 | 372 | // among the three. |
jmasa@448 | 373 | |
jmasa@448 | 374 | // Final check min <= initial <= max |
jmasa@448 | 375 | set_min_gen0_size(MIN2(_min_gen0_size, _max_gen0_size)); |
jmasa@448 | 376 | set_initial_gen0_size( |
jmasa@448 | 377 | MAX2(MIN2(_initial_gen0_size, _max_gen0_size), _min_gen0_size)); |
jmasa@448 | 378 | set_min_gen0_size(MIN2(_min_gen0_size, _initial_gen0_size)); |
duke@435 | 379 | } |
duke@435 | 380 | |
jmasa@448 | 381 | if (PrintGCDetails && Verbose) { |
ysr@2650 | 382 | gclog_or_tty->print_cr("1: Minimum gen0 " SIZE_FORMAT " Initial gen0 " |
jmasa@448 | 383 | SIZE_FORMAT " Maximum gen0 " SIZE_FORMAT, |
jmasa@448 | 384 | min_gen0_size(), initial_gen0_size(), max_gen0_size()); |
jmasa@448 | 385 | } |
jmasa@448 | 386 | } |
duke@435 | 387 | |
jmasa@448 | 388 | // Call this method during the sizing of the gen1 to make |
jmasa@448 | 389 | // adjustments to gen0 because of gen1 sizing policy. gen0 initially has |
jmasa@448 | 390 | // the most freedom in sizing because it is done before the |
jmasa@448 | 391 | // policy for gen1 is applied. Once gen1 policies have been applied, |
jmasa@448 | 392 | // there may be conflicts in the shape of the heap and this method |
jmasa@448 | 393 | // is used to make the needed adjustments. The application of the |
jmasa@448 | 394 | // policies could be more sophisticated (iterative for example) but |
jmasa@448 | 395 | // keeping it simple also seems a worthwhile goal. |
jmasa@448 | 396 | bool TwoGenerationCollectorPolicy::adjust_gen0_sizes(size_t* gen0_size_ptr, |
jmasa@448 | 397 | size_t* gen1_size_ptr, |
jmasa@448 | 398 | size_t heap_size, |
jmasa@448 | 399 | size_t min_gen0_size) { |
jmasa@448 | 400 | bool result = false; |
jmasa@448 | 401 | if ((*gen1_size_ptr + *gen0_size_ptr) > heap_size) { |
jmasa@448 | 402 | if (((*gen0_size_ptr + OldSize) > heap_size) && |
jmasa@448 | 403 | (heap_size - min_gen0_size) >= min_alignment()) { |
jmasa@448 | 404 | // Adjust gen0 down to accomodate OldSize |
jmasa@448 | 405 | *gen0_size_ptr = heap_size - min_gen0_size; |
jmasa@448 | 406 | *gen0_size_ptr = |
jmasa@448 | 407 | MAX2((uintx)align_size_down(*gen0_size_ptr, min_alignment()), |
jmasa@448 | 408 | min_alignment()); |
jmasa@448 | 409 | assert(*gen0_size_ptr > 0, "Min gen0 is too large"); |
jmasa@448 | 410 | result = true; |
jmasa@448 | 411 | } else { |
jmasa@448 | 412 | *gen1_size_ptr = heap_size - *gen0_size_ptr; |
jmasa@448 | 413 | *gen1_size_ptr = |
jmasa@448 | 414 | MAX2((uintx)align_size_down(*gen1_size_ptr, min_alignment()), |
jmasa@448 | 415 | min_alignment()); |
jmasa@448 | 416 | } |
jmasa@448 | 417 | } |
jmasa@448 | 418 | return result; |
jmasa@448 | 419 | } |
duke@435 | 420 | |
jmasa@448 | 421 | // Minimum sizes of the generations may be different than |
jmasa@448 | 422 | // the initial sizes. An inconsistently is permitted here |
jmasa@448 | 423 | // in the total size that can be specified explicitly by |
jmasa@448 | 424 | // command line specification of OldSize and NewSize and |
jmasa@448 | 425 | // also a command line specification of -Xms. Issue a warning |
jmasa@448 | 426 | // but allow the values to pass. |
duke@435 | 427 | |
duke@435 | 428 | void TwoGenerationCollectorPolicy::initialize_size_info() { |
duke@435 | 429 | GenCollectorPolicy::initialize_size_info(); |
duke@435 | 430 | |
jmasa@448 | 431 | // At this point the minimum, initial and maximum sizes |
jmasa@448 | 432 | // of the overall heap and of gen0 have been determined. |
jmasa@448 | 433 | // The maximum gen1 size can be determined from the maximum gen0 |
ysr@2650 | 434 | // and maximum heap size since no explicit flags exits |
jmasa@448 | 435 | // for setting the gen1 maximum. |
jmasa@448 | 436 | _max_gen1_size = max_heap_byte_size() - _max_gen0_size; |
jmasa@448 | 437 | _max_gen1_size = |
jmasa@448 | 438 | MAX2((uintx)align_size_down(_max_gen1_size, min_alignment()), |
jmasa@448 | 439 | min_alignment()); |
jmasa@448 | 440 | // If no explicit command line flag has been set for the |
jmasa@448 | 441 | // gen1 size, use what is left for gen1. |
jmasa@448 | 442 | if (FLAG_IS_DEFAULT(OldSize) || FLAG_IS_ERGO(OldSize)) { |
jmasa@448 | 443 | // The user has not specified any value or ergonomics |
jmasa@448 | 444 | // has chosen a value (which may or may not be consistent |
jmasa@448 | 445 | // with the overall heap size). In either case make |
jmasa@448 | 446 | // the minimum, maximum and initial sizes consistent |
jmasa@448 | 447 | // with the gen0 sizes and the overall heap sizes. |
jmasa@448 | 448 | assert(min_heap_byte_size() > _min_gen0_size, |
jmasa@448 | 449 | "gen0 has an unexpected minimum size"); |
jmasa@448 | 450 | set_min_gen1_size(min_heap_byte_size() - min_gen0_size()); |
jmasa@448 | 451 | set_min_gen1_size( |
jmasa@448 | 452 | MAX2((uintx)align_size_down(_min_gen1_size, min_alignment()), |
jmasa@448 | 453 | min_alignment())); |
jmasa@448 | 454 | set_initial_gen1_size(initial_heap_byte_size() - initial_gen0_size()); |
jmasa@448 | 455 | set_initial_gen1_size( |
jmasa@448 | 456 | MAX2((uintx)align_size_down(_initial_gen1_size, min_alignment()), |
jmasa@448 | 457 | min_alignment())); |
jmasa@448 | 458 | |
jmasa@448 | 459 | } else { |
jmasa@448 | 460 | // It's been explicitly set on the command line. Use the |
jmasa@448 | 461 | // OldSize and then determine the consequences. |
jmasa@448 | 462 | set_min_gen1_size(OldSize); |
jmasa@448 | 463 | set_initial_gen1_size(OldSize); |
jmasa@448 | 464 | |
jmasa@448 | 465 | // If the user has explicitly set an OldSize that is inconsistent |
jmasa@448 | 466 | // with other command line flags, issue a warning. |
duke@435 | 467 | // The generation minimums and the overall heap mimimum should |
duke@435 | 468 | // be within one heap alignment. |
jmasa@448 | 469 | if ((_min_gen1_size + _min_gen0_size + min_alignment()) < |
jmasa@448 | 470 | min_heap_byte_size()) { |
duke@435 | 471 | warning("Inconsistency between minimum heap size and minimum " |
jmasa@448 | 472 | "generation sizes: using minimum heap = " SIZE_FORMAT, |
jmasa@448 | 473 | min_heap_byte_size()); |
duke@435 | 474 | } |
jmasa@448 | 475 | if ((OldSize > _max_gen1_size)) { |
jmasa@448 | 476 | warning("Inconsistency between maximum heap size and maximum " |
jmasa@448 | 477 | "generation sizes: using maximum heap = " SIZE_FORMAT |
jmasa@448 | 478 | " -XX:OldSize flag is being ignored", |
jmasa@448 | 479 | max_heap_byte_size()); |
ysr@2650 | 480 | } |
jmasa@448 | 481 | // If there is an inconsistency between the OldSize and the minimum and/or |
jmasa@448 | 482 | // initial size of gen0, since OldSize was explicitly set, OldSize wins. |
jmasa@448 | 483 | if (adjust_gen0_sizes(&_min_gen0_size, &_min_gen1_size, |
jmasa@448 | 484 | min_heap_byte_size(), OldSize)) { |
jmasa@448 | 485 | if (PrintGCDetails && Verbose) { |
ysr@2650 | 486 | gclog_or_tty->print_cr("2: Minimum gen0 " SIZE_FORMAT " Initial gen0 " |
jmasa@448 | 487 | SIZE_FORMAT " Maximum gen0 " SIZE_FORMAT, |
jmasa@448 | 488 | min_gen0_size(), initial_gen0_size(), max_gen0_size()); |
jmasa@448 | 489 | } |
jmasa@448 | 490 | } |
jmasa@448 | 491 | // Initial size |
jmasa@448 | 492 | if (adjust_gen0_sizes(&_initial_gen0_size, &_initial_gen1_size, |
jmasa@448 | 493 | initial_heap_byte_size(), OldSize)) { |
jmasa@448 | 494 | if (PrintGCDetails && Verbose) { |
ysr@2650 | 495 | gclog_or_tty->print_cr("3: Minimum gen0 " SIZE_FORMAT " Initial gen0 " |
jmasa@448 | 496 | SIZE_FORMAT " Maximum gen0 " SIZE_FORMAT, |
jmasa@448 | 497 | min_gen0_size(), initial_gen0_size(), max_gen0_size()); |
jmasa@448 | 498 | } |
jmasa@448 | 499 | } |
jmasa@448 | 500 | } |
jmasa@448 | 501 | // Enforce the maximum gen1 size. |
jmasa@448 | 502 | set_min_gen1_size(MIN2(_min_gen1_size, _max_gen1_size)); |
duke@435 | 503 | |
jmasa@448 | 504 | // Check that min gen1 <= initial gen1 <= max gen1 |
jmasa@448 | 505 | set_initial_gen1_size(MAX2(_initial_gen1_size, _min_gen1_size)); |
jmasa@448 | 506 | set_initial_gen1_size(MIN2(_initial_gen1_size, _max_gen1_size)); |
jmasa@448 | 507 | |
jmasa@448 | 508 | if (PrintGCDetails && Verbose) { |
jmasa@448 | 509 | gclog_or_tty->print_cr("Minimum gen1 " SIZE_FORMAT " Initial gen1 " |
jmasa@448 | 510 | SIZE_FORMAT " Maximum gen1 " SIZE_FORMAT, |
jmasa@448 | 511 | min_gen1_size(), initial_gen1_size(), max_gen1_size()); |
jmasa@448 | 512 | } |
duke@435 | 513 | } |
duke@435 | 514 | |
duke@435 | 515 | HeapWord* GenCollectorPolicy::mem_allocate_work(size_t size, |
duke@435 | 516 | bool is_tlab, |
duke@435 | 517 | bool* gc_overhead_limit_was_exceeded) { |
duke@435 | 518 | GenCollectedHeap *gch = GenCollectedHeap::heap(); |
duke@435 | 519 | |
duke@435 | 520 | debug_only(gch->check_for_valid_allocation_state()); |
duke@435 | 521 | assert(gch->no_gc_in_progress(), "Allocation during gc not allowed"); |
jmasa@1822 | 522 | |
jmasa@1822 | 523 | // In general gc_overhead_limit_was_exceeded should be false so |
jmasa@1822 | 524 | // set it so here and reset it to true only if the gc time |
jmasa@1822 | 525 | // limit is being exceeded as checked below. |
jmasa@1822 | 526 | *gc_overhead_limit_was_exceeded = false; |
jmasa@1822 | 527 | |
duke@435 | 528 | HeapWord* result = NULL; |
duke@435 | 529 | |
duke@435 | 530 | // Loop until the allocation is satisified, |
duke@435 | 531 | // or unsatisfied after GC. |
duke@435 | 532 | for (int try_count = 1; /* return or throw */; try_count += 1) { |
duke@435 | 533 | HandleMark hm; // discard any handles allocated in each iteration |
duke@435 | 534 | |
duke@435 | 535 | // First allocation attempt is lock-free. |
duke@435 | 536 | Generation *gen0 = gch->get_gen(0); |
duke@435 | 537 | assert(gen0->supports_inline_contig_alloc(), |
duke@435 | 538 | "Otherwise, must do alloc within heap lock"); |
duke@435 | 539 | if (gen0->should_allocate(size, is_tlab)) { |
duke@435 | 540 | result = gen0->par_allocate(size, is_tlab); |
duke@435 | 541 | if (result != NULL) { |
duke@435 | 542 | assert(gch->is_in_reserved(result), "result not in heap"); |
duke@435 | 543 | return result; |
duke@435 | 544 | } |
duke@435 | 545 | } |
duke@435 | 546 | unsigned int gc_count_before; // read inside the Heap_lock locked region |
duke@435 | 547 | { |
duke@435 | 548 | MutexLocker ml(Heap_lock); |
duke@435 | 549 | if (PrintGC && Verbose) { |
duke@435 | 550 | gclog_or_tty->print_cr("TwoGenerationCollectorPolicy::mem_allocate_work:" |
duke@435 | 551 | " attempting locked slow path allocation"); |
duke@435 | 552 | } |
duke@435 | 553 | // Note that only large objects get a shot at being |
duke@435 | 554 | // allocated in later generations. |
duke@435 | 555 | bool first_only = ! should_try_older_generation_allocation(size); |
duke@435 | 556 | |
duke@435 | 557 | result = gch->attempt_allocation(size, is_tlab, first_only); |
duke@435 | 558 | if (result != NULL) { |
duke@435 | 559 | assert(gch->is_in_reserved(result), "result not in heap"); |
duke@435 | 560 | return result; |
duke@435 | 561 | } |
duke@435 | 562 | |
duke@435 | 563 | if (GC_locker::is_active_and_needs_gc()) { |
duke@435 | 564 | if (is_tlab) { |
duke@435 | 565 | return NULL; // Caller will retry allocating individual object |
duke@435 | 566 | } |
duke@435 | 567 | if (!gch->is_maximal_no_gc()) { |
duke@435 | 568 | // Try and expand heap to satisfy request |
duke@435 | 569 | result = expand_heap_and_allocate(size, is_tlab); |
duke@435 | 570 | // result could be null if we are out of space |
duke@435 | 571 | if (result != NULL) { |
duke@435 | 572 | return result; |
duke@435 | 573 | } |
duke@435 | 574 | } |
duke@435 | 575 | |
duke@435 | 576 | // If this thread is not in a jni critical section, we stall |
duke@435 | 577 | // the requestor until the critical section has cleared and |
duke@435 | 578 | // GC allowed. When the critical section clears, a GC is |
duke@435 | 579 | // initiated by the last thread exiting the critical section; so |
duke@435 | 580 | // we retry the allocation sequence from the beginning of the loop, |
duke@435 | 581 | // rather than causing more, now probably unnecessary, GC attempts. |
duke@435 | 582 | JavaThread* jthr = JavaThread::current(); |
duke@435 | 583 | if (!jthr->in_critical()) { |
duke@435 | 584 | MutexUnlocker mul(Heap_lock); |
duke@435 | 585 | // Wait for JNI critical section to be exited |
duke@435 | 586 | GC_locker::stall_until_clear(); |
duke@435 | 587 | continue; |
duke@435 | 588 | } else { |
duke@435 | 589 | if (CheckJNICalls) { |
duke@435 | 590 | fatal("Possible deadlock due to allocating while" |
duke@435 | 591 | " in jni critical section"); |
duke@435 | 592 | } |
duke@435 | 593 | return NULL; |
duke@435 | 594 | } |
duke@435 | 595 | } |
duke@435 | 596 | |
duke@435 | 597 | // Read the gc count while the heap lock is held. |
duke@435 | 598 | gc_count_before = Universe::heap()->total_collections(); |
duke@435 | 599 | } |
duke@435 | 600 | |
duke@435 | 601 | VM_GenCollectForAllocation op(size, |
duke@435 | 602 | is_tlab, |
duke@435 | 603 | gc_count_before); |
duke@435 | 604 | VMThread::execute(&op); |
duke@435 | 605 | if (op.prologue_succeeded()) { |
duke@435 | 606 | result = op.result(); |
duke@435 | 607 | if (op.gc_locked()) { |
duke@435 | 608 | assert(result == NULL, "must be NULL if gc_locked() is true"); |
duke@435 | 609 | continue; // retry and/or stall as necessary |
duke@435 | 610 | } |
jmasa@1822 | 611 | |
jmasa@1822 | 612 | // Allocation has failed and a collection |
jmasa@1822 | 613 | // has been done. If the gc time limit was exceeded the |
jmasa@1822 | 614 | // this time, return NULL so that an out-of-memory |
jmasa@1822 | 615 | // will be thrown. Clear gc_overhead_limit_exceeded |
jmasa@1822 | 616 | // so that the overhead exceeded does not persist. |
jmasa@1822 | 617 | |
jmasa@1822 | 618 | const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded(); |
jmasa@1822 | 619 | const bool softrefs_clear = all_soft_refs_clear(); |
jmasa@1822 | 620 | assert(!limit_exceeded || softrefs_clear, "Should have been cleared"); |
jmasa@1822 | 621 | if (limit_exceeded && softrefs_clear) { |
jmasa@1822 | 622 | *gc_overhead_limit_was_exceeded = true; |
jmasa@1822 | 623 | size_policy()->set_gc_overhead_limit_exceeded(false); |
jmasa@1822 | 624 | if (op.result() != NULL) { |
jmasa@1822 | 625 | CollectedHeap::fill_with_object(op.result(), size); |
jmasa@1822 | 626 | } |
jmasa@1822 | 627 | return NULL; |
jmasa@1822 | 628 | } |
duke@435 | 629 | assert(result == NULL || gch->is_in_reserved(result), |
duke@435 | 630 | "result not in heap"); |
duke@435 | 631 | return result; |
duke@435 | 632 | } |
duke@435 | 633 | |
duke@435 | 634 | // Give a warning if we seem to be looping forever. |
duke@435 | 635 | if ((QueuedAllocationWarningCount > 0) && |
duke@435 | 636 | (try_count % QueuedAllocationWarningCount == 0)) { |
duke@435 | 637 | warning("TwoGenerationCollectorPolicy::mem_allocate_work retries %d times \n\t" |
duke@435 | 638 | " size=%d %s", try_count, size, is_tlab ? "(TLAB)" : ""); |
duke@435 | 639 | } |
duke@435 | 640 | } |
duke@435 | 641 | } |
duke@435 | 642 | |
duke@435 | 643 | HeapWord* GenCollectorPolicy::expand_heap_and_allocate(size_t size, |
duke@435 | 644 | bool is_tlab) { |
duke@435 | 645 | GenCollectedHeap *gch = GenCollectedHeap::heap(); |
duke@435 | 646 | HeapWord* result = NULL; |
duke@435 | 647 | for (int i = number_of_generations() - 1; i >= 0 && result == NULL; i--) { |
duke@435 | 648 | Generation *gen = gch->get_gen(i); |
duke@435 | 649 | if (gen->should_allocate(size, is_tlab)) { |
duke@435 | 650 | result = gen->expand_and_allocate(size, is_tlab); |
duke@435 | 651 | } |
duke@435 | 652 | } |
duke@435 | 653 | assert(result == NULL || gch->is_in_reserved(result), "result not in heap"); |
duke@435 | 654 | return result; |
duke@435 | 655 | } |
duke@435 | 656 | |
duke@435 | 657 | HeapWord* GenCollectorPolicy::satisfy_failed_allocation(size_t size, |
duke@435 | 658 | bool is_tlab) { |
duke@435 | 659 | GenCollectedHeap *gch = GenCollectedHeap::heap(); |
duke@435 | 660 | GCCauseSetter x(gch, GCCause::_allocation_failure); |
duke@435 | 661 | HeapWord* result = NULL; |
duke@435 | 662 | |
duke@435 | 663 | assert(size != 0, "Precondition violated"); |
duke@435 | 664 | if (GC_locker::is_active_and_needs_gc()) { |
duke@435 | 665 | // GC locker is active; instead of a collection we will attempt |
duke@435 | 666 | // to expand the heap, if there's room for expansion. |
duke@435 | 667 | if (!gch->is_maximal_no_gc()) { |
duke@435 | 668 | result = expand_heap_and_allocate(size, is_tlab); |
duke@435 | 669 | } |
duke@435 | 670 | return result; // could be null if we are out of space |
ysr@2336 | 671 | } else if (!gch->incremental_collection_will_fail(false /* don't consult_young */)) { |
duke@435 | 672 | // Do an incremental collection. |
duke@435 | 673 | gch->do_collection(false /* full */, |
duke@435 | 674 | false /* clear_all_soft_refs */, |
duke@435 | 675 | size /* size */, |
duke@435 | 676 | is_tlab /* is_tlab */, |
duke@435 | 677 | number_of_generations() - 1 /* max_level */); |
duke@435 | 678 | } else { |
ysr@2336 | 679 | if (Verbose && PrintGCDetails) { |
ysr@2336 | 680 | gclog_or_tty->print(" :: Trying full because partial may fail :: "); |
ysr@2336 | 681 | } |
duke@435 | 682 | // Try a full collection; see delta for bug id 6266275 |
duke@435 | 683 | // for the original code and why this has been simplified |
duke@435 | 684 | // with from-space allocation criteria modified and |
duke@435 | 685 | // such allocation moved out of the safepoint path. |
duke@435 | 686 | gch->do_collection(true /* full */, |
duke@435 | 687 | false /* clear_all_soft_refs */, |
duke@435 | 688 | size /* size */, |
duke@435 | 689 | is_tlab /* is_tlab */, |
duke@435 | 690 | number_of_generations() - 1 /* max_level */); |
duke@435 | 691 | } |
duke@435 | 692 | |
duke@435 | 693 | result = gch->attempt_allocation(size, is_tlab, false /*first_only*/); |
duke@435 | 694 | |
duke@435 | 695 | if (result != NULL) { |
duke@435 | 696 | assert(gch->is_in_reserved(result), "result not in heap"); |
duke@435 | 697 | return result; |
duke@435 | 698 | } |
duke@435 | 699 | |
duke@435 | 700 | // OK, collection failed, try expansion. |
duke@435 | 701 | result = expand_heap_and_allocate(size, is_tlab); |
duke@435 | 702 | if (result != NULL) { |
duke@435 | 703 | return result; |
duke@435 | 704 | } |
duke@435 | 705 | |
duke@435 | 706 | // If we reach this point, we're really out of memory. Try every trick |
duke@435 | 707 | // we can to reclaim memory. Force collection of soft references. Force |
duke@435 | 708 | // a complete compaction of the heap. Any additional methods for finding |
duke@435 | 709 | // free memory should be here, especially if they are expensive. If this |
duke@435 | 710 | // attempt fails, an OOM exception will be thrown. |
duke@435 | 711 | { |
duke@435 | 712 | IntFlagSetting flag_change(MarkSweepAlwaysCompactCount, 1); // Make sure the heap is fully compacted |
duke@435 | 713 | |
duke@435 | 714 | gch->do_collection(true /* full */, |
duke@435 | 715 | true /* clear_all_soft_refs */, |
duke@435 | 716 | size /* size */, |
duke@435 | 717 | is_tlab /* is_tlab */, |
duke@435 | 718 | number_of_generations() - 1 /* max_level */); |
duke@435 | 719 | } |
duke@435 | 720 | |
duke@435 | 721 | result = gch->attempt_allocation(size, is_tlab, false /* first_only */); |
duke@435 | 722 | if (result != NULL) { |
duke@435 | 723 | assert(gch->is_in_reserved(result), "result not in heap"); |
duke@435 | 724 | return result; |
duke@435 | 725 | } |
duke@435 | 726 | |
jmasa@1822 | 727 | assert(!should_clear_all_soft_refs(), |
jmasa@1822 | 728 | "Flag should have been handled and cleared prior to this point"); |
jmasa@1822 | 729 | |
duke@435 | 730 | // What else? We might try synchronous finalization later. If the total |
duke@435 | 731 | // space available is large enough for the allocation, then a more |
duke@435 | 732 | // complete compaction phase than we've tried so far might be |
duke@435 | 733 | // appropriate. |
duke@435 | 734 | return NULL; |
duke@435 | 735 | } |
duke@435 | 736 | |
coleenp@4037 | 737 | MetaWord* CollectorPolicy::satisfy_failed_metadata_allocation( |
coleenp@4037 | 738 | ClassLoaderData* loader_data, |
coleenp@4037 | 739 | size_t word_size, |
coleenp@4037 | 740 | Metaspace::MetadataType mdtype) { |
coleenp@4037 | 741 | uint loop_count = 0; |
coleenp@4037 | 742 | uint gc_count = 0; |
coleenp@4037 | 743 | uint full_gc_count = 0; |
coleenp@4037 | 744 | |
coleenp@4037 | 745 | do { |
jmasa@4064 | 746 | MetaWord* result = NULL; |
jmasa@4064 | 747 | if (GC_locker::is_active_and_needs_gc()) { |
jmasa@4064 | 748 | // If the GC_locker is active, just expand and allocate. |
jmasa@4064 | 749 | // If that does not succeed, wait if this thread is not |
jmasa@4064 | 750 | // in a critical section itself. |
jmasa@4064 | 751 | result = |
jmasa@4064 | 752 | loader_data->metaspace_non_null()->expand_and_allocate(word_size, |
jmasa@4064 | 753 | mdtype); |
jmasa@4064 | 754 | if (result != NULL) { |
jmasa@4064 | 755 | return result; |
jmasa@4064 | 756 | } |
jmasa@4064 | 757 | JavaThread* jthr = JavaThread::current(); |
jmasa@4064 | 758 | if (!jthr->in_critical()) { |
jmasa@4064 | 759 | MutexUnlocker mul(Heap_lock); |
jmasa@4064 | 760 | // Wait for JNI critical section to be exited |
jmasa@4064 | 761 | GC_locker::stall_until_clear(); |
jmasa@4064 | 762 | // The GC invoked by the last thread leaving the critical |
jmasa@4064 | 763 | // section will be a young collection and a full collection |
jmasa@4064 | 764 | // is (currently) needed for unloading classes so continue |
jmasa@4064 | 765 | // to the next iteration to get a full GC. |
jmasa@4064 | 766 | continue; |
jmasa@4064 | 767 | } else { |
jmasa@4064 | 768 | if (CheckJNICalls) { |
jmasa@4064 | 769 | fatal("Possible deadlock due to allocating while" |
jmasa@4064 | 770 | " in jni critical section"); |
jmasa@4064 | 771 | } |
jmasa@4064 | 772 | return NULL; |
jmasa@4064 | 773 | } |
jmasa@4064 | 774 | } |
jmasa@4064 | 775 | |
coleenp@4037 | 776 | { // Need lock to get self consistent gc_count's |
coleenp@4037 | 777 | MutexLocker ml(Heap_lock); |
coleenp@4037 | 778 | gc_count = Universe::heap()->total_collections(); |
coleenp@4037 | 779 | full_gc_count = Universe::heap()->total_full_collections(); |
coleenp@4037 | 780 | } |
coleenp@4037 | 781 | |
coleenp@4037 | 782 | // Generate a VM operation |
coleenp@4037 | 783 | VM_CollectForMetadataAllocation op(loader_data, |
coleenp@4037 | 784 | word_size, |
coleenp@4037 | 785 | mdtype, |
coleenp@4037 | 786 | gc_count, |
coleenp@4037 | 787 | full_gc_count, |
coleenp@4037 | 788 | GCCause::_metadata_GC_threshold); |
coleenp@4037 | 789 | VMThread::execute(&op); |
coleenp@4037 | 790 | if (op.prologue_succeeded()) { |
coleenp@4037 | 791 | return op.result(); |
coleenp@4037 | 792 | } |
coleenp@4037 | 793 | loop_count++; |
coleenp@4037 | 794 | if ((QueuedAllocationWarningCount > 0) && |
coleenp@4037 | 795 | (loop_count % QueuedAllocationWarningCount == 0)) { |
coleenp@4037 | 796 | warning("satisfy_failed_metadata_allocation() retries %d times \n\t" |
coleenp@4037 | 797 | " size=%d", loop_count, word_size); |
coleenp@4037 | 798 | } |
coleenp@4037 | 799 | } while (true); // Until a GC is done |
coleenp@4037 | 800 | } |
coleenp@4037 | 801 | |
duke@435 | 802 | // Return true if any of the following is true: |
duke@435 | 803 | // . the allocation won't fit into the current young gen heap |
duke@435 | 804 | // . gc locker is occupied (jni critical section) |
duke@435 | 805 | // . heap memory is tight -- the most recent previous collection |
duke@435 | 806 | // was a full collection because a partial collection (would |
duke@435 | 807 | // have) failed and is likely to fail again |
duke@435 | 808 | bool GenCollectorPolicy::should_try_older_generation_allocation( |
duke@435 | 809 | size_t word_size) const { |
duke@435 | 810 | GenCollectedHeap* gch = GenCollectedHeap::heap(); |
duke@435 | 811 | size_t gen0_capacity = gch->get_gen(0)->capacity_before_gc(); |
duke@435 | 812 | return (word_size > heap_word_size(gen0_capacity)) |
ysr@2243 | 813 | || GC_locker::is_active_and_needs_gc() |
ysr@2243 | 814 | || gch->incremental_collection_failed(); |
duke@435 | 815 | } |
duke@435 | 816 | |
duke@435 | 817 | |
duke@435 | 818 | // |
duke@435 | 819 | // MarkSweepPolicy methods |
duke@435 | 820 | // |
duke@435 | 821 | |
duke@435 | 822 | MarkSweepPolicy::MarkSweepPolicy() { |
duke@435 | 823 | initialize_all(); |
duke@435 | 824 | } |
duke@435 | 825 | |
duke@435 | 826 | void MarkSweepPolicy::initialize_generations() { |
duke@435 | 827 | _generations = new GenerationSpecPtr[number_of_generations()]; |
duke@435 | 828 | if (_generations == NULL) |
duke@435 | 829 | vm_exit_during_initialization("Unable to allocate gen spec"); |
duke@435 | 830 | |
duke@435 | 831 | if (UseParNewGC && ParallelGCThreads > 0) { |
duke@435 | 832 | _generations[0] = new GenerationSpec(Generation::ParNew, _initial_gen0_size, _max_gen0_size); |
duke@435 | 833 | } else { |
duke@435 | 834 | _generations[0] = new GenerationSpec(Generation::DefNew, _initial_gen0_size, _max_gen0_size); |
duke@435 | 835 | } |
duke@435 | 836 | _generations[1] = new GenerationSpec(Generation::MarkSweepCompact, _initial_gen1_size, _max_gen1_size); |
duke@435 | 837 | |
duke@435 | 838 | if (_generations[0] == NULL || _generations[1] == NULL) |
duke@435 | 839 | vm_exit_during_initialization("Unable to allocate gen spec"); |
duke@435 | 840 | } |
duke@435 | 841 | |
duke@435 | 842 | void MarkSweepPolicy::initialize_gc_policy_counters() { |
duke@435 | 843 | // initialize the policy counters - 2 collectors, 3 generations |
duke@435 | 844 | if (UseParNewGC && ParallelGCThreads > 0) { |
duke@435 | 845 | _gc_policy_counters = new GCPolicyCounters("ParNew:MSC", 2, 3); |
duke@435 | 846 | } |
duke@435 | 847 | else { |
duke@435 | 848 | _gc_policy_counters = new GCPolicyCounters("Copy:MSC", 2, 3); |
duke@435 | 849 | } |
duke@435 | 850 | } |