/* * Copyright (c) 2011, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "aot/aotLoader.hpp" #include "classfile/classLoaderDataGraph.hpp" #include "gc/shared/collectedHeap.hpp" #include "logging/log.hpp" #include "logging/logStream.hpp" #include "memory/filemap.hpp" #include "memory/metaspace.hpp" #include "memory/metaspace/chunkManager.hpp" #include "memory/metaspace/metachunk.hpp" #include "memory/metaspace/metaspaceCommon.hpp" #include "memory/metaspace/printCLDMetaspaceInfoClosure.hpp" #include "memory/metaspace/spaceManager.hpp" #include "memory/metaspace/virtualSpaceList.hpp" #include "memory/metaspaceShared.hpp" #include "memory/metaspaceTracer.hpp" #include "memory/universe.hpp" #include "runtime/init.hpp" #include "runtime/orderAccess.hpp" #include "services/memTracker.hpp" #include "utilities/copy.hpp" #include "utilities/debug.hpp" #include "utilities/formatBuffer.hpp" #include "utilities/globalDefinitions.hpp" using namespace metaspace; MetaWord* last_allocated = 0; size_t Metaspace::_compressed_class_space_size; const MetaspaceTracer* Metaspace::_tracer = NULL; DEBUG_ONLY(bool Metaspace::_frozen = false;) static const char* space_type_name(Metaspace::MetaspaceType t) { const char* s = NULL; switch (t) { case Metaspace::StandardMetaspaceType: s = "Standard"; break; case Metaspace::BootMetaspaceType: s = "Boot"; break; case Metaspace::UnsafeAnonymousMetaspaceType: s = "UnsafeAnonymous"; break; case Metaspace::ReflectionMetaspaceType: s = "Reflection"; break; default: ShouldNotReachHere(); } return s; } volatile size_t MetaspaceGC::_capacity_until_GC = 0; uint MetaspaceGC::_shrink_factor = 0; bool MetaspaceGC::_should_concurrent_collect = false; // BlockFreelist methods // VirtualSpaceNode methods // MetaspaceGC methods // VM_CollectForMetadataAllocation is the vm operation used to GC. // Within the VM operation after the GC the attempt to allocate the metadata // should succeed. If the GC did not free enough space for the metaspace // allocation, the HWM is increased so that another virtualspace will be // allocated for the metadata. With perm gen the increase in the perm // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion. The // metaspace policy uses those as the small and large steps for the HWM. // // After the GC the compute_new_size() for MetaspaceGC is called to // resize the capacity of the metaspaces. The current implementation // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used // to resize the Java heap by some GC's. New flags can be implemented // if really needed. MinMetaspaceFreeRatio is used to calculate how much // free space is desirable in the metaspace capacity to decide how much // to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much // free space is desirable in the metaspace capacity before decreasing // the HWM. // Calculate the amount to increase the high water mark (HWM). // Increase by a minimum amount (MinMetaspaceExpansion) so that // another expansion is not requested too soon. If that is not // enough to satisfy the allocation, increase by MaxMetaspaceExpansion. // If that is still not enough, expand by the size of the allocation // plus some. size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) { size_t min_delta = MinMetaspaceExpansion; size_t max_delta = MaxMetaspaceExpansion; size_t delta = align_up(bytes, Metaspace::commit_alignment()); if (delta <= min_delta) { delta = min_delta; } else if (delta <= max_delta) { // Don't want to hit the high water mark on the next // allocation so make the delta greater than just enough // for this allocation. delta = max_delta; } else { // This allocation is large but the next ones are probably not // so increase by the minimum. delta = delta + min_delta; } assert_is_aligned(delta, Metaspace::commit_alignment()); return delta; } size_t MetaspaceGC::capacity_until_GC() { size_t value = OrderAccess::load_acquire(&_capacity_until_GC); assert(value >= MetaspaceSize, "Not initialized properly?"); return value; } bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC) { assert_is_aligned(v, Metaspace::commit_alignment()); size_t old_capacity_until_GC = _capacity_until_GC; size_t new_value = old_capacity_until_GC + v; if (new_value < old_capacity_until_GC) { // The addition wrapped around, set new_value to aligned max value. new_value = align_down(max_uintx, Metaspace::commit_alignment()); } if (new_value > MaxMetaspaceSize) { return false; } size_t prev_value = Atomic::cmpxchg(new_value, &_capacity_until_GC, old_capacity_until_GC); if (old_capacity_until_GC != prev_value) { return false; } if (new_cap_until_GC != NULL) { *new_cap_until_GC = new_value; } if (old_cap_until_GC != NULL) { *old_cap_until_GC = old_capacity_until_GC; } return true; } size_t MetaspaceGC::dec_capacity_until_GC(size_t v) { assert_is_aligned(v, Metaspace::commit_alignment()); return Atomic::sub(v, &_capacity_until_GC); } void MetaspaceGC::initialize() { // Set the high-water mark to MaxMetapaceSize during VM initializaton since // we can't do a GC during initialization. _capacity_until_GC = MaxMetaspaceSize; } void MetaspaceGC::post_initialize() { // Reset the high-water mark once the VM initialization is done. _capacity_until_GC = MAX2(MetaspaceUtils::committed_bytes(), MetaspaceSize); } bool MetaspaceGC::can_expand(size_t word_size, bool is_class) { // Check if the compressed class space is full. if (is_class && Metaspace::using_class_space()) { size_t class_committed = MetaspaceUtils::committed_bytes(Metaspace::ClassType); if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) { log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (CompressedClassSpaceSize = " SIZE_FORMAT " words)", (is_class ? "class" : "non-class"), word_size, CompressedClassSpaceSize / sizeof(MetaWord)); return false; } } // Check if the user has imposed a limit on the metaspace memory. size_t committed_bytes = MetaspaceUtils::committed_bytes(); if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) { log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (MaxMetaspaceSize = " SIZE_FORMAT " words)", (is_class ? "class" : "non-class"), word_size, MaxMetaspaceSize / sizeof(MetaWord)); return false; } return true; } size_t MetaspaceGC::allowed_expansion() { size_t committed_bytes = MetaspaceUtils::committed_bytes(); size_t capacity_until_gc = capacity_until_GC(); assert(capacity_until_gc >= committed_bytes, "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT, capacity_until_gc, committed_bytes); size_t left_until_max = MaxMetaspaceSize - committed_bytes; size_t left_until_GC = capacity_until_gc - committed_bytes; size_t left_to_commit = MIN2(left_until_GC, left_until_max); log_trace(gc, metaspace, freelist)("allowed expansion words: " SIZE_FORMAT " (left_until_max: " SIZE_FORMAT ", left_until_GC: " SIZE_FORMAT ".", left_to_commit / BytesPerWord, left_until_max / BytesPerWord, left_until_GC / BytesPerWord); return left_to_commit / BytesPerWord; } void MetaspaceGC::compute_new_size() { assert(_shrink_factor <= 100, "invalid shrink factor"); uint current_shrink_factor = _shrink_factor; _shrink_factor = 0; // Using committed_bytes() for used_after_gc is an overestimation, since the // chunk free lists are included in committed_bytes() and the memory in an // un-fragmented chunk free list is available for future allocations. // However, if the chunk free lists becomes fragmented, then the memory may // not be available for future allocations and the memory is therefore "in use". // Including the chunk free lists in the definition of "in use" is therefore // necessary. Not including the chunk free lists can cause capacity_until_GC to // shrink below committed_bytes() and this has caused serious bugs in the past. const size_t used_after_gc = MetaspaceUtils::committed_bytes(); const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC(); const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0; const double maximum_used_percentage = 1.0 - minimum_free_percentage; const double min_tmp = used_after_gc / maximum_used_percentage; size_t minimum_desired_capacity = (size_t)MIN2(min_tmp, double(MaxMetaspaceSize)); // Don't shrink less than the initial generation size minimum_desired_capacity = MAX2(minimum_desired_capacity, MetaspaceSize); log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: "); log_trace(gc, metaspace)(" minimum_free_percentage: %6.2f maximum_used_percentage: %6.2f", minimum_free_percentage, maximum_used_percentage); log_trace(gc, metaspace)(" used_after_gc : %6.1fKB", used_after_gc / (double) K); size_t shrink_bytes = 0; if (capacity_until_GC < minimum_desired_capacity) { // If we have less capacity below the metaspace HWM, then // increment the HWM. size_t expand_bytes = minimum_desired_capacity - capacity_until_GC; expand_bytes = align_up(expand_bytes, Metaspace::commit_alignment()); // Don't expand unless it's significant if (expand_bytes >= MinMetaspaceExpansion) { size_t new_capacity_until_GC = 0; bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC); assert(succeeded, "Should always succesfully increment HWM when at safepoint"); Metaspace::tracer()->report_gc_threshold(capacity_until_GC, new_capacity_until_GC, MetaspaceGCThresholdUpdater::ComputeNewSize); log_trace(gc, metaspace)(" expanding: minimum_desired_capacity: %6.1fKB expand_bytes: %6.1fKB MinMetaspaceExpansion: %6.1fKB new metaspace HWM: %6.1fKB", minimum_desired_capacity / (double) K, expand_bytes / (double) K, MinMetaspaceExpansion / (double) K, new_capacity_until_GC / (double) K); } return; } // No expansion, now see if we want to shrink // We would never want to shrink more than this assert(capacity_until_GC >= minimum_desired_capacity, SIZE_FORMAT " >= " SIZE_FORMAT, capacity_until_GC, minimum_desired_capacity); size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity; // Should shrinking be considered? if (MaxMetaspaceFreeRatio < 100) { const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0; const double minimum_used_percentage = 1.0 - maximum_free_percentage; const double max_tmp = used_after_gc / minimum_used_percentage; size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(MaxMetaspaceSize)); maximum_desired_capacity = MAX2(maximum_desired_capacity, MetaspaceSize); log_trace(gc, metaspace)(" maximum_free_percentage: %6.2f minimum_used_percentage: %6.2f", maximum_free_percentage, minimum_used_percentage); log_trace(gc, metaspace)(" minimum_desired_capacity: %6.1fKB maximum_desired_capacity: %6.1fKB", minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K); assert(minimum_desired_capacity <= maximum_desired_capacity, "sanity check"); if (capacity_until_GC > maximum_desired_capacity) { // Capacity too large, compute shrinking size shrink_bytes = capacity_until_GC - maximum_desired_capacity; // We don't want shrink all the way back to initSize if people call // System.gc(), because some programs do that between "phases" and then // we'd just have to grow the heap up again for the next phase. So we // damp the shrinking: 0% on the first call, 10% on the second call, 40% // on the third call, and 100% by the fourth call. But if we recompute // size without shrinking, it goes back to 0%. shrink_bytes = shrink_bytes / 100 * current_shrink_factor; shrink_bytes = align_down(shrink_bytes, Metaspace::commit_alignment()); assert(shrink_bytes <= max_shrink_bytes, "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT, shrink_bytes, max_shrink_bytes); if (current_shrink_factor == 0) { _shrink_factor = 10; } else { _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100); } log_trace(gc, metaspace)(" shrinking: initThreshold: %.1fK maximum_desired_capacity: %.1fK", MetaspaceSize / (double) K, maximum_desired_capacity / (double) K); log_trace(gc, metaspace)(" shrink_bytes: %.1fK current_shrink_factor: %d new shrink factor: %d MinMetaspaceExpansion: %.1fK", shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K); } } // Don't shrink unless it's significant if (shrink_bytes >= MinMetaspaceExpansion && ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) { size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes); Metaspace::tracer()->report_gc_threshold(capacity_until_GC, new_capacity_until_GC, MetaspaceGCThresholdUpdater::ComputeNewSize); } } // MetaspaceUtils size_t MetaspaceUtils::_capacity_words [Metaspace:: MetadataTypeCount] = {0, 0}; size_t MetaspaceUtils::_overhead_words [Metaspace:: MetadataTypeCount] = {0, 0}; volatile size_t MetaspaceUtils::_used_words [Metaspace:: MetadataTypeCount] = {0, 0}; // Collect used metaspace statistics. This involves walking the CLDG. The resulting // output will be the accumulated values for all live metaspaces. // Note: method does not do any locking. void MetaspaceUtils::collect_statistics(ClassLoaderMetaspaceStatistics* out) { out->reset(); ClassLoaderDataGraphMetaspaceIterator iter; while (iter.repeat()) { ClassLoaderMetaspace* msp = iter.get_next(); if (msp != NULL) { msp->add_to_statistics(out); } } } size_t MetaspaceUtils::free_in_vs_bytes(Metaspace::MetadataType mdtype) { VirtualSpaceList* list = Metaspace::get_space_list(mdtype); return list == NULL ? 0 : list->free_bytes(); } size_t MetaspaceUtils::free_in_vs_bytes() { return free_in_vs_bytes(Metaspace::ClassType) + free_in_vs_bytes(Metaspace::NonClassType); } static void inc_stat_nonatomically(size_t* pstat, size_t words) { assert_lock_strong(MetaspaceExpand_lock); (*pstat) += words; } static void dec_stat_nonatomically(size_t* pstat, size_t words) { assert_lock_strong(MetaspaceExpand_lock); const size_t size_now = *pstat; assert(size_now >= words, "About to decrement counter below zero " "(current value: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ".", size_now, words); *pstat = size_now - words; } static void inc_stat_atomically(volatile size_t* pstat, size_t words) { Atomic::add(words, pstat); } static void dec_stat_atomically(volatile size_t* pstat, size_t words) { const size_t size_now = *pstat; assert(size_now >= words, "About to decrement counter below zero " "(current value: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ".", size_now, words); Atomic::sub(words, pstat); } void MetaspaceUtils::dec_capacity(Metaspace::MetadataType mdtype, size_t words) { dec_stat_nonatomically(&_capacity_words[mdtype], words); } void MetaspaceUtils::inc_capacity(Metaspace::MetadataType mdtype, size_t words) { inc_stat_nonatomically(&_capacity_words[mdtype], words); } void MetaspaceUtils::dec_used(Metaspace::MetadataType mdtype, size_t words) { dec_stat_atomically(&_used_words[mdtype], words); } void MetaspaceUtils::inc_used(Metaspace::MetadataType mdtype, size_t words) { inc_stat_atomically(&_used_words[mdtype], words); } void MetaspaceUtils::dec_overhead(Metaspace::MetadataType mdtype, size_t words) { dec_stat_nonatomically(&_overhead_words[mdtype], words); } void MetaspaceUtils::inc_overhead(Metaspace::MetadataType mdtype, size_t words) { inc_stat_nonatomically(&_overhead_words[mdtype], words); } size_t MetaspaceUtils::reserved_bytes(Metaspace::MetadataType mdtype) { VirtualSpaceList* list = Metaspace::get_space_list(mdtype); return list == NULL ? 0 : list->reserved_bytes(); } size_t MetaspaceUtils::committed_bytes(Metaspace::MetadataType mdtype) { VirtualSpaceList* list = Metaspace::get_space_list(mdtype); return list == NULL ? 0 : list->committed_bytes(); } size_t MetaspaceUtils::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); } size_t MetaspaceUtils::free_chunks_total_words(Metaspace::MetadataType mdtype) { ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype); if (chunk_manager == NULL) { return 0; } chunk_manager->slow_verify(); return chunk_manager->free_chunks_total_words(); } size_t MetaspaceUtils::free_chunks_total_bytes(Metaspace::MetadataType mdtype) { return free_chunks_total_words(mdtype) * BytesPerWord; } size_t MetaspaceUtils::free_chunks_total_words() { return free_chunks_total_words(Metaspace::ClassType) + free_chunks_total_words(Metaspace::NonClassType); } size_t MetaspaceUtils::free_chunks_total_bytes() { return free_chunks_total_words() * BytesPerWord; } bool MetaspaceUtils::has_chunk_free_list(Metaspace::MetadataType mdtype) { return Metaspace::get_chunk_manager(mdtype) != NULL; } MetaspaceChunkFreeListSummary MetaspaceUtils::chunk_free_list_summary(Metaspace::MetadataType mdtype) { if (!has_chunk_free_list(mdtype)) { return MetaspaceChunkFreeListSummary(); } const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype); return cm->chunk_free_list_summary(); } void MetaspaceUtils::print_metaspace_change(size_t prev_metadata_used) { log_info(gc, metaspace)("Metaspace: " SIZE_FORMAT "K->" SIZE_FORMAT "K(" SIZE_FORMAT "K)", prev_metadata_used/K, used_bytes()/K, reserved_bytes()/K); } void MetaspaceUtils::print_on(outputStream* out) { Metaspace::MetadataType nct = Metaspace::NonClassType; out->print_cr(" Metaspace " "used " SIZE_FORMAT "K, " "capacity " SIZE_FORMAT "K, " "committed " SIZE_FORMAT "K, " "reserved " SIZE_FORMAT "K", used_bytes()/K, capacity_bytes()/K, committed_bytes()/K, reserved_bytes()/K); if (Metaspace::using_class_space()) { Metaspace::MetadataType ct = Metaspace::ClassType; out->print_cr(" class space " "used " SIZE_FORMAT "K, " "capacity " SIZE_FORMAT "K, " "committed " SIZE_FORMAT "K, " "reserved " SIZE_FORMAT "K", used_bytes(ct)/K, capacity_bytes(ct)/K, committed_bytes(ct)/K, reserved_bytes(ct)/K); } } void MetaspaceUtils::print_vs(outputStream* out, size_t scale) { const size_t reserved_nonclass_words = reserved_bytes(Metaspace::NonClassType) / sizeof(MetaWord); const size_t committed_nonclass_words = committed_bytes(Metaspace::NonClassType) / sizeof(MetaWord); { if (Metaspace::using_class_space()) { out->print(" Non-class space: "); } print_scaled_words(out, reserved_nonclass_words, scale, 7); out->print(" reserved, "); print_scaled_words_and_percentage(out, committed_nonclass_words, reserved_nonclass_words, scale, 7); out->print_cr(" committed "); if (Metaspace::using_class_space()) { const size_t reserved_class_words = reserved_bytes(Metaspace::ClassType) / sizeof(MetaWord); const size_t committed_class_words = committed_bytes(Metaspace::ClassType) / sizeof(MetaWord); out->print(" Class space: "); print_scaled_words(out, reserved_class_words, scale, 7); out->print(" reserved, "); print_scaled_words_and_percentage(out, committed_class_words, reserved_class_words, scale, 7); out->print_cr(" committed "); const size_t reserved_words = reserved_nonclass_words + reserved_class_words; const size_t committed_words = committed_nonclass_words + committed_class_words; out->print(" Both: "); print_scaled_words(out, reserved_words, scale, 7); out->print(" reserved, "); print_scaled_words_and_percentage(out, committed_words, reserved_words, scale, 7); out->print_cr(" committed "); } } } // This will print out a basic metaspace usage report but // unlike print_report() is guaranteed not to lock or to walk the CLDG. void MetaspaceUtils::print_basic_report(outputStream* out, size_t scale) { out->cr(); out->print_cr("Usage:"); if (Metaspace::using_class_space()) { out->print(" Non-class: "); } // In its most basic form, we do not require walking the CLDG. Instead, just print the running totals from // MetaspaceUtils. const size_t cap_nc = MetaspaceUtils::capacity_words(Metaspace::NonClassType); const size_t overhead_nc = MetaspaceUtils::overhead_words(Metaspace::NonClassType); const size_t used_nc = MetaspaceUtils::used_words(Metaspace::NonClassType); const size_t free_and_waste_nc = cap_nc - overhead_nc - used_nc; print_scaled_words(out, cap_nc, scale, 5); out->print(" capacity, "); print_scaled_words_and_percentage(out, used_nc, cap_nc, scale, 5); out->print(" used, "); print_scaled_words_and_percentage(out, free_and_waste_nc, cap_nc, scale, 5); out->print(" free+waste, "); print_scaled_words_and_percentage(out, overhead_nc, cap_nc, scale, 5); out->print(" overhead. "); out->cr(); if (Metaspace::using_class_space()) { const size_t cap_c = MetaspaceUtils::capacity_words(Metaspace::ClassType); const size_t overhead_c = MetaspaceUtils::overhead_words(Metaspace::ClassType); const size_t used_c = MetaspaceUtils::used_words(Metaspace::ClassType); const size_t free_and_waste_c = cap_c - overhead_c - used_c; out->print(" Class: "); print_scaled_words(out, cap_c, scale, 5); out->print(" capacity, "); print_scaled_words_and_percentage(out, used_c, cap_c, scale, 5); out->print(" used, "); print_scaled_words_and_percentage(out, free_and_waste_c, cap_c, scale, 5); out->print(" free+waste, "); print_scaled_words_and_percentage(out, overhead_c, cap_c, scale, 5); out->print(" overhead. "); out->cr(); out->print(" Both: "); const size_t cap = cap_nc + cap_c; print_scaled_words(out, cap, scale, 5); out->print(" capacity, "); print_scaled_words_and_percentage(out, used_nc + used_c, cap, scale, 5); out->print(" used, "); print_scaled_words_and_percentage(out, free_and_waste_nc + free_and_waste_c, cap, scale, 5); out->print(" free+waste, "); print_scaled_words_and_percentage(out, overhead_nc + overhead_c, cap, scale, 5); out->print(" overhead. "); out->cr(); } out->cr(); out->print_cr("Virtual space:"); print_vs(out, scale); out->cr(); out->print_cr("Chunk freelists:"); if (Metaspace::using_class_space()) { out->print(" Non-Class: "); } print_human_readable_size(out, Metaspace::chunk_manager_metadata()->free_chunks_total_words(), scale); out->cr(); if (Metaspace::using_class_space()) { out->print(" Class: "); print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_words(), scale); out->cr(); out->print(" Both: "); print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_words() + Metaspace::chunk_manager_metadata()->free_chunks_total_words(), scale); out->cr(); } out->cr(); } void MetaspaceUtils::print_report(outputStream* out, size_t scale, int flags) { const bool print_loaders = (flags & rf_show_loaders) > 0; const bool print_classes = (flags & rf_show_classes) > 0; const bool print_by_chunktype = (flags & rf_break_down_by_chunktype) > 0; const bool print_by_spacetype = (flags & rf_break_down_by_spacetype) > 0; // Some report options require walking the class loader data graph. PrintCLDMetaspaceInfoClosure cl(out, scale, print_loaders, print_classes, print_by_chunktype); if (print_loaders) { out->cr(); out->print_cr("Usage per loader:"); out->cr(); } ClassLoaderDataGraph::loaded_cld_do(&cl); // collect data and optionally print // Print totals, broken up by space type. if (print_by_spacetype) { out->cr(); out->print_cr("Usage per space type:"); out->cr(); for (int space_type = (int)Metaspace::ZeroMetaspaceType; space_type < (int)Metaspace::MetaspaceTypeCount; space_type ++) { uintx num = cl._num_loaders_by_spacetype[space_type]; out->print("%s (" UINTX_FORMAT " loader%s)%c", space_type_name((Metaspace::MetaspaceType)space_type), num, (num == 1 ? "" : "s"), (num > 0 ? ':' : '.')); if (num > 0) { cl._stats_by_spacetype[space_type].print_on(out, scale, print_by_chunktype); } out->cr(); } } // Print totals for in-use data: out->cr(); out->print_cr("Total Usage ( " UINTX_FORMAT " loader%s)%c", cl._num_loaders, (cl._num_loaders == 1 ? "" : "s"), (cl._num_loaders > 0 ? ':' : '.')); cl._stats_total.print_on(out, scale, print_by_chunktype); // -- Print Virtual space. out->cr(); out->print_cr("Virtual space:"); print_vs(out, scale); // -- Print VirtualSpaceList details. if ((flags & rf_show_vslist) > 0) { out->cr(); out->print_cr("Virtual space list%s:", Metaspace::using_class_space() ? "s" : ""); if (Metaspace::using_class_space()) { out->print_cr(" Non-Class:"); } Metaspace::space_list()->print_on(out, scale); if (Metaspace::using_class_space()) { out->print_cr(" Class:"); Metaspace::class_space_list()->print_on(out, scale); } } out->cr(); // -- Print VirtualSpaceList map. if ((flags & rf_show_vsmap) > 0) { out->cr(); out->print_cr("Virtual space map:"); if (Metaspace::using_class_space()) { out->print_cr(" Non-Class:"); } Metaspace::space_list()->print_map(out); if (Metaspace::using_class_space()) { out->print_cr(" Class:"); Metaspace::class_space_list()->print_map(out); } } out->cr(); // -- Print Freelists (ChunkManager) details out->cr(); out->print_cr("Chunk freelist%s:", Metaspace::using_class_space() ? "s" : ""); ChunkManagerStatistics non_class_cm_stat; Metaspace::chunk_manager_metadata()->collect_statistics(&non_class_cm_stat); if (Metaspace::using_class_space()) { out->print_cr(" Non-Class:"); } non_class_cm_stat.print_on(out, scale); if (Metaspace::using_class_space()) { ChunkManagerStatistics class_cm_stat; Metaspace::chunk_manager_class()->collect_statistics(&class_cm_stat); out->print_cr(" Class:"); class_cm_stat.print_on(out, scale); } // As a convenience, print a summary of common waste. out->cr(); out->print("Waste "); // For all wastages, print percentages from total. As total use the total size of memory committed for metaspace. const size_t committed_words = committed_bytes() / BytesPerWord; out->print("(percentages refer to total committed size "); print_scaled_words(out, committed_words, scale); out->print_cr("):"); // Print space committed but not yet used by any class loader const size_t unused_words_in_vs = MetaspaceUtils::free_in_vs_bytes() / BytesPerWord; out->print(" Committed unused: "); print_scaled_words_and_percentage(out, unused_words_in_vs, committed_words, scale, 6); out->cr(); // Print waste for in-use chunks. UsedChunksStatistics ucs_nonclass = cl._stats_total.nonclass_sm_stats().totals(); UsedChunksStatistics ucs_class = cl._stats_total.class_sm_stats().totals(); UsedChunksStatistics ucs_all; ucs_all.add(ucs_nonclass); ucs_all.add(ucs_class); out->print(" Waste in chunks in use: "); print_scaled_words_and_percentage(out, ucs_all.waste(), committed_words, scale, 6); out->cr(); out->print(" Free in chunks in use: "); print_scaled_words_and_percentage(out, ucs_all.free(), committed_words, scale, 6); out->cr(); out->print(" Overhead in chunks in use: "); print_scaled_words_and_percentage(out, ucs_all.overhead(), committed_words, scale, 6); out->cr(); // Print waste in free chunks. const size_t total_capacity_in_free_chunks = Metaspace::chunk_manager_metadata()->free_chunks_total_words() + (Metaspace::using_class_space() ? Metaspace::chunk_manager_class()->free_chunks_total_words() : 0); out->print(" In free chunks: "); print_scaled_words_and_percentage(out, total_capacity_in_free_chunks, committed_words, scale, 6); out->cr(); // Print waste in deallocated blocks. const uintx free_blocks_num = cl._stats_total.nonclass_sm_stats().free_blocks_num() + cl._stats_total.class_sm_stats().free_blocks_num(); const size_t free_blocks_cap_words = cl._stats_total.nonclass_sm_stats().free_blocks_cap_words() + cl._stats_total.class_sm_stats().free_blocks_cap_words(); out->print("Deallocated from chunks in use: "); print_scaled_words_and_percentage(out, free_blocks_cap_words, committed_words, scale, 6); out->print(" (" UINTX_FORMAT " blocks)", free_blocks_num); out->cr(); // Print total waste. const size_t total_waste = ucs_all.waste() + ucs_all.free() + ucs_all.overhead() + total_capacity_in_free_chunks + free_blocks_cap_words + unused_words_in_vs; out->print(" -total-: "); print_scaled_words_and_percentage(out, total_waste, committed_words, scale, 6); out->cr(); // Print internal statistics #ifdef ASSERT out->cr(); out->cr(); out->print_cr("Internal statistics:"); out->cr(); out->print_cr("Number of allocations: " UINTX_FORMAT ".", g_internal_statistics.num_allocs); out->print_cr("Number of space births: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_births); out->print_cr("Number of space deaths: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_deaths); out->print_cr("Number of virtual space node births: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_created); out->print_cr("Number of virtual space node deaths: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_purged); out->print_cr("Number of times virtual space nodes were expanded: " UINTX_FORMAT ".", g_internal_statistics.num_committed_space_expanded); out->print_cr("Number of deallocations: " UINTX_FORMAT " (" UINTX_FORMAT " external).", g_internal_statistics.num_deallocs, g_internal_statistics.num_external_deallocs); out->print_cr("Allocations from deallocated blocks: " UINTX_FORMAT ".", g_internal_statistics.num_allocs_from_deallocated_blocks); out->cr(); #endif // Print some interesting settings out->cr(); out->cr(); out->print("MaxMetaspaceSize: "); print_human_readable_size(out, MaxMetaspaceSize, scale); out->cr(); out->print("InitialBootClassLoaderMetaspaceSize: "); print_human_readable_size(out, InitialBootClassLoaderMetaspaceSize, scale); out->cr(); out->print("UseCompressedClassPointers: %s", UseCompressedClassPointers ? "true" : "false"); out->cr(); if (Metaspace::using_class_space()) { out->print("CompressedClassSpaceSize: "); print_human_readable_size(out, CompressedClassSpaceSize, scale); } out->cr(); out->cr(); } // MetaspaceUtils::print_report() // Prints an ASCII representation of the given space. void MetaspaceUtils::print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype) { MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); const bool for_class = mdtype == Metaspace::ClassType ? true : false; VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list(); if (vsl != NULL) { if (for_class) { if (!Metaspace::using_class_space()) { out->print_cr("No Class Space."); return; } out->print_raw("---- Metaspace Map (Class Space) ----"); } else { out->print_raw("---- Metaspace Map (Non-Class Space) ----"); } // Print legend: out->cr(); out->print_cr("Chunk Types (uppercase chunks are in use): x-specialized, s-small, m-medium, h-humongous."); out->cr(); VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list(); vsl->print_map(out); out->cr(); } } void MetaspaceUtils::verify_free_chunks() { Metaspace::chunk_manager_metadata()->verify(); if (Metaspace::using_class_space()) { Metaspace::chunk_manager_class()->verify(); } } void MetaspaceUtils::verify_metrics() { #ifdef ASSERT // Please note: there are time windows where the internal counters are out of sync with // reality. For example, when a newly created ClassLoaderMetaspace creates its first chunk - // the ClassLoaderMetaspace is not yet attached to its ClassLoaderData object and hence will // not be counted when iterating the CLDG. So be careful when you call this method. ClassLoaderMetaspaceStatistics total_stat; collect_statistics(&total_stat); UsedChunksStatistics nonclass_chunk_stat = total_stat.nonclass_sm_stats().totals(); UsedChunksStatistics class_chunk_stat = total_stat.class_sm_stats().totals(); bool mismatch = false; for (int i = 0; i < Metaspace::MetadataTypeCount; i ++) { Metaspace::MetadataType mdtype = (Metaspace::MetadataType)i; UsedChunksStatistics chunk_stat = total_stat.sm_stats(mdtype).totals(); if (capacity_words(mdtype) != chunk_stat.cap() || used_words(mdtype) != chunk_stat.used() || overhead_words(mdtype) != chunk_stat.overhead()) { mismatch = true; tty->print_cr("MetaspaceUtils::verify_metrics: counter mismatch for mdtype=%u:", mdtype); tty->print_cr("Expected cap " SIZE_FORMAT ", used " SIZE_FORMAT ", overhead " SIZE_FORMAT ".", capacity_words(mdtype), used_words(mdtype), overhead_words(mdtype)); tty->print_cr("Got cap " SIZE_FORMAT ", used " SIZE_FORMAT ", overhead " SIZE_FORMAT ".", chunk_stat.cap(), chunk_stat.used(), chunk_stat.overhead()); tty->flush(); } } assert(mismatch == false, "MetaspaceUtils::verify_metrics: counter mismatch."); #endif } // Utils to check if a pointer or range is part of a committed metaspace region. metaspace::VirtualSpaceNode* MetaspaceUtils::find_enclosing_virtual_space(const void* p) { MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); VirtualSpaceNode* vsn = Metaspace::space_list()->find_enclosing_space(p); if (Metaspace::using_class_space() && vsn == NULL) { vsn = Metaspace::class_space_list()->find_enclosing_space(p); } return vsn; } bool MetaspaceUtils::is_in_committed(const void* p) { #if INCLUDE_CDS if (UseSharedSpaces) { for (int idx = MetaspaceShared::ro; idx <= MetaspaceShared::mc; idx++) { if (FileMapInfo::current_info()->is_in_shared_region(p, idx)) { return true; } } } #endif return find_enclosing_virtual_space(p) != NULL; } bool MetaspaceUtils::is_range_in_committed(const void* from, const void* to) { #if INCLUDE_CDS if (UseSharedSpaces) { for (int idx = MetaspaceShared::ro; idx <= MetaspaceShared::mc; idx++) { if (FileMapInfo::current_info()->is_in_shared_region(from, idx)) { return FileMapInfo::current_info()->is_in_shared_region(to, idx); } } } #endif VirtualSpaceNode* vsn = find_enclosing_virtual_space(from); return (vsn != NULL) && vsn->contains(to); } // Metaspace methods size_t Metaspace::_first_chunk_word_size = 0; size_t Metaspace::_first_class_chunk_word_size = 0; size_t Metaspace::_commit_alignment = 0; size_t Metaspace::_reserve_alignment = 0; VirtualSpaceList* Metaspace::_space_list = NULL; VirtualSpaceList* Metaspace::_class_space_list = NULL; ChunkManager* Metaspace::_chunk_manager_metadata = NULL; ChunkManager* Metaspace::_chunk_manager_class = NULL; #define VIRTUALSPACEMULTIPLIER 2 #ifdef _LP64 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1); void Metaspace::set_narrow_klass_base_and_shift(address metaspace_base, address cds_base) { assert(!DumpSharedSpaces, "narrow_klass is set by MetaspaceShared class."); // Figure out the narrow_klass_base and the narrow_klass_shift. The // narrow_klass_base is the lower of the metaspace base and the cds base // (if cds is enabled). The narrow_klass_shift depends on the distance // between the lower base and higher address. address lower_base; address higher_address; #if INCLUDE_CDS if (UseSharedSpaces) { higher_address = MAX2((address)(cds_base + MetaspaceShared::core_spaces_size()), (address)(metaspace_base + compressed_class_space_size())); lower_base = MIN2(metaspace_base, cds_base); } else #endif { higher_address = metaspace_base + compressed_class_space_size(); lower_base = metaspace_base; uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes; // If compressed class space fits in lower 32G, we don't need a base. if (higher_address <= (address)klass_encoding_max) { lower_base = 0; // Effectively lower base is zero. } } Universe::set_narrow_klass_base(lower_base); // CDS uses LogKlassAlignmentInBytes for narrow_klass_shift. See // MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() for // how dump time narrow_klass_shift is set. Although, CDS can work // with zero-shift mode also, to be consistent with AOT it uses // LogKlassAlignmentInBytes for klass shift so archived java heap objects // can be used at same time as AOT code. if (!UseSharedSpaces && (uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) { Universe::set_narrow_klass_shift(0); } else { Universe::set_narrow_klass_shift(LogKlassAlignmentInBytes); } AOTLoader::set_narrow_klass_shift(); } #if INCLUDE_CDS // Return TRUE if the specified metaspace_base and cds_base are close enough // to work with compressed klass pointers. bool Metaspace::can_use_cds_with_metaspace_addr(char* metaspace_base, address cds_base) { assert(cds_base != 0 && UseSharedSpaces, "Only use with CDS"); assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); address lower_base = MIN2((address)metaspace_base, cds_base); address higher_address = MAX2((address)(cds_base + MetaspaceShared::core_spaces_size()), (address)(metaspace_base + compressed_class_space_size())); return ((uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax); } #endif // Try to allocate the metaspace at the requested addr. void Metaspace::allocate_metaspace_compressed_klass_ptrs(char* requested_addr, address cds_base) { assert(!DumpSharedSpaces, "compress klass space is allocated by MetaspaceShared class."); assert(using_class_space(), "called improperly"); assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs"); assert(compressed_class_space_size() < KlassEncodingMetaspaceMax, "Metaspace size is too big"); assert_is_aligned(requested_addr, _reserve_alignment); assert_is_aligned(cds_base, _reserve_alignment); assert_is_aligned(compressed_class_space_size(), _reserve_alignment); // Don't use large pages for the class space. bool large_pages = false; #if !(defined(AARCH64) || defined(AIX)) ReservedSpace metaspace_rs = ReservedSpace(compressed_class_space_size(), _reserve_alignment, large_pages, requested_addr); #else // AARCH64 ReservedSpace metaspace_rs; // Our compressed klass pointers may fit nicely into the lower 32 // bits. if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) { metaspace_rs = ReservedSpace(compressed_class_space_size(), _reserve_alignment, large_pages, requested_addr); } if (! metaspace_rs.is_reserved()) { // Aarch64: Try to align metaspace so that we can decode a compressed // klass with a single MOVK instruction. We can do this iff the // compressed class base is a multiple of 4G. // Aix: Search for a place where we can find memory. If we need to load // the base, 4G alignment is helpful, too. size_t increment = AARCH64_ONLY(4*)G; for (char *a = align_up(requested_addr, increment); a < (char*)(1024*G); a += increment) { if (a == (char *)(32*G)) { // Go faster from here on. Zero-based is no longer possible. increment = 4*G; } #if INCLUDE_CDS if (UseSharedSpaces && ! can_use_cds_with_metaspace_addr(a, cds_base)) { // We failed to find an aligned base that will reach. Fall // back to using our requested addr. metaspace_rs = ReservedSpace(compressed_class_space_size(), _reserve_alignment, large_pages, requested_addr); break; } #endif metaspace_rs = ReservedSpace(compressed_class_space_size(), _reserve_alignment, large_pages, a); if (metaspace_rs.is_reserved()) break; } } #endif // AARCH64 if (!metaspace_rs.is_reserved()) { #if INCLUDE_CDS if (UseSharedSpaces) { size_t increment = align_up(1*G, _reserve_alignment); // Keep trying to allocate the metaspace, increasing the requested_addr // by 1GB each time, until we reach an address that will no longer allow // use of CDS with compressed klass pointers. char *addr = requested_addr; while (!metaspace_rs.is_reserved() && (addr + increment > addr) && can_use_cds_with_metaspace_addr(addr + increment, cds_base)) { addr = addr + increment; metaspace_rs = ReservedSpace(compressed_class_space_size(), _reserve_alignment, large_pages, addr); } } #endif // If no successful allocation then try to allocate the space anywhere. If // that fails then OOM doom. At this point we cannot try allocating the // metaspace as if UseCompressedClassPointers is off because too much // initialization has happened that depends on UseCompressedClassPointers. // So, UseCompressedClassPointers cannot be turned off at this point. if (!metaspace_rs.is_reserved()) { metaspace_rs = ReservedSpace(compressed_class_space_size(), _reserve_alignment, large_pages); if (!metaspace_rs.is_reserved()) { vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes", compressed_class_space_size())); } } } // If we got here then the metaspace got allocated. MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass); #if INCLUDE_CDS // Verify that we can use shared spaces. Otherwise, turn off CDS. if (UseSharedSpaces && !can_use_cds_with_metaspace_addr(metaspace_rs.base(), cds_base)) { FileMapInfo::stop_sharing_and_unmap( "Could not allocate metaspace at a compatible address"); } #endif set_narrow_klass_base_and_shift((address)metaspace_rs.base(), UseSharedSpaces ? (address)cds_base : 0); initialize_class_space(metaspace_rs); LogTarget(Trace, gc, metaspace) lt; if (lt.is_enabled()) { ResourceMark rm; LogStream ls(lt); print_compressed_class_space(&ls, requested_addr); } } void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) { st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d", p2i(Universe::narrow_klass_base()), Universe::narrow_klass_shift()); if (_class_space_list != NULL) { address base = (address)_class_space_list->current_virtual_space()->bottom(); st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT, compressed_class_space_size(), p2i(base)); if (requested_addr != 0) { st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr)); } st->cr(); } } // For UseCompressedClassPointers the class space is reserved above the top of // the Java heap. The argument passed in is at the base of the compressed space. void Metaspace::initialize_class_space(ReservedSpace rs) { // The reserved space size may be bigger because of alignment, esp with UseLargePages assert(rs.size() >= CompressedClassSpaceSize, SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize); assert(using_class_space(), "Must be using class space"); _class_space_list = new VirtualSpaceList(rs); _chunk_manager_class = new ChunkManager(true/*is_class*/); if (!_class_space_list->initialization_succeeded()) { vm_exit_during_initialization("Failed to setup compressed class space virtual space list."); } } #endif void Metaspace::ergo_initialize() { if (DumpSharedSpaces) { // Using large pages when dumping the shared archive is currently not implemented. FLAG_SET_ERGO(bool, UseLargePagesInMetaspace, false); } size_t page_size = os::vm_page_size(); if (UseLargePages && UseLargePagesInMetaspace) { page_size = os::large_page_size(); } _commit_alignment = page_size; _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will // override if MaxMetaspaceSize was set on the command line or not. // This information is needed later to conform to the specification of the // java.lang.management.MemoryUsage API. // // Ideally, we would be able to set the default value of MaxMetaspaceSize in // globals.hpp to the aligned value, but this is not possible, since the // alignment depends on other flags being parsed. MaxMetaspaceSize = align_down_bounded(MaxMetaspaceSize, _reserve_alignment); if (MetaspaceSize > MaxMetaspaceSize) { MetaspaceSize = MaxMetaspaceSize; } MetaspaceSize = align_down_bounded(MetaspaceSize, _commit_alignment); assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize"); MinMetaspaceExpansion = align_down_bounded(MinMetaspaceExpansion, _commit_alignment); MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment); CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment); // Initial virtual space size will be calculated at global_initialize() size_t min_metaspace_sz = VIRTUALSPACEMULTIPLIER * InitialBootClassLoaderMetaspaceSize; if (UseCompressedClassPointers) { if ((min_metaspace_sz + CompressedClassSpaceSize) > MaxMetaspaceSize) { if (min_metaspace_sz >= MaxMetaspaceSize) { vm_exit_during_initialization("MaxMetaspaceSize is too small."); } else { FLAG_SET_ERGO(size_t, CompressedClassSpaceSize, MaxMetaspaceSize - min_metaspace_sz); } } } else if (min_metaspace_sz >= MaxMetaspaceSize) { FLAG_SET_ERGO(size_t, InitialBootClassLoaderMetaspaceSize, min_metaspace_sz); } set_compressed_class_space_size(CompressedClassSpaceSize); } void Metaspace::global_initialize() { MetaspaceGC::initialize(); #if INCLUDE_CDS if (DumpSharedSpaces) { MetaspaceShared::initialize_dumptime_shared_and_meta_spaces(); } else if (UseSharedSpaces) { // If any of the archived space fails to map, UseSharedSpaces // is reset to false. Fall through to the // (!DumpSharedSpaces && !UseSharedSpaces) case to set up class // metaspace. MetaspaceShared::initialize_runtime_shared_and_meta_spaces(); } if (!DumpSharedSpaces && !UseSharedSpaces) #endif // INCLUDE_CDS { #ifdef _LP64 if (using_class_space()) { char* base = (char*)align_up(Universe::heap()->reserved_region().end(), _reserve_alignment); allocate_metaspace_compressed_klass_ptrs(base, 0); } #endif // _LP64 } // Initialize these before initializing the VirtualSpaceList _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord; _first_chunk_word_size = align_word_size_up(_first_chunk_word_size); // Make the first class chunk bigger than a medium chunk so it's not put // on the medium chunk list. The next chunk will be small and progress // from there. This size calculated by -version. _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6, (CompressedClassSpaceSize/BytesPerWord)*2); _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size); // Arbitrarily set the initial virtual space to a multiple // of the boot class loader size. size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size; word_size = align_up(word_size, Metaspace::reserve_alignment_words()); // Initialize the list of virtual spaces. _space_list = new VirtualSpaceList(word_size); _chunk_manager_metadata = new ChunkManager(false/*metaspace*/); if (!_space_list->initialization_succeeded()) { vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL); } _tracer = new MetaspaceTracer(); } void Metaspace::post_initialize() { MetaspaceGC::post_initialize(); } void Metaspace::verify_global_initialization() { assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized"); assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized"); if (using_class_space()) { assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized"); assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized"); } } size_t Metaspace::align_word_size_up(size_t word_size) { size_t byte_size = word_size * wordSize; return ReservedSpace::allocation_align_size_up(byte_size) / wordSize; } MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, TRAPS) { assert(!_frozen, "sanity"); assert(!(DumpSharedSpaces && THREAD->is_VM_thread()), "sanity"); if (HAS_PENDING_EXCEPTION) { assert(false, "Should not allocate with exception pending"); return NULL; // caller does a CHECK_NULL too } assert(loader_data != NULL, "Should never pass around a NULL loader_data. " "ClassLoaderData::the_null_class_loader_data() should have been used."); MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType; // Try to allocate metadata. MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype); if (result == NULL) { tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype); // Allocation failed. if (is_init_completed()) { // Only start a GC if the bootstrapping has completed. // Try to clean out some heap memory and retry. This can prevent premature // expansion of the metaspace. result = Universe::heap()->satisfy_failed_metadata_allocation(loader_data, word_size, mdtype); } } if (result == NULL) { if (DumpSharedSpaces) { // CDS dumping keeps loading classes, so if we hit an OOM we probably will keep hitting OOM. // We should abort to avoid generating a potentially bad archive. vm_exit_during_cds_dumping(err_msg("Failed allocating metaspace object type %s of size " SIZE_FORMAT ". CDS dump aborted.", MetaspaceObj::type_name(type), word_size * BytesPerWord), err_msg("Please increase MaxMetaspaceSize (currently " SIZE_FORMAT " bytes).", MaxMetaspaceSize)); } report_metadata_oome(loader_data, word_size, type, mdtype, THREAD); assert(HAS_PENDING_EXCEPTION, "sanity"); return NULL; } // Zero initialize. Copy::fill_to_words((HeapWord*)result, word_size, 0); return result; } void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) { tracer()->report_metadata_oom(loader_data, word_size, type, mdtype); // If result is still null, we are out of memory. Log(gc, metaspace, freelist, oom) log; if (log.is_info()) { log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT, is_class_space_allocation(mdtype) ? "class" : "data", word_size); ResourceMark rm; if (log.is_debug()) { if (loader_data->metaspace_or_null() != NULL) { LogStream ls(log.debug()); loader_data->print_value_on(&ls); } } LogStream ls(log.info()); // In case of an OOM, log out a short but still useful report. MetaspaceUtils::print_basic_report(&ls, 0); } bool out_of_compressed_class_space = false; if (is_class_space_allocation(mdtype)) { ClassLoaderMetaspace* metaspace = loader_data->metaspace_non_null(); out_of_compressed_class_space = MetaspaceUtils::committed_bytes(Metaspace::ClassType) + (metaspace->class_chunk_size(word_size) * BytesPerWord) > CompressedClassSpaceSize; } // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support const char* space_string = out_of_compressed_class_space ? "Compressed class space" : "Metaspace"; report_java_out_of_memory(space_string); if (JvmtiExport::should_post_resource_exhausted()) { JvmtiExport::post_resource_exhausted( JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, space_string); } if (!is_init_completed()) { vm_exit_during_initialization("OutOfMemoryError", space_string); } if (out_of_compressed_class_space) { THROW_OOP(Universe::out_of_memory_error_class_metaspace()); } else { THROW_OOP(Universe::out_of_memory_error_metaspace()); } } const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) { switch (mdtype) { case Metaspace::ClassType: return "Class"; case Metaspace::NonClassType: return "Metadata"; default: assert(false, "Got bad mdtype: %d", (int) mdtype); return NULL; } } void Metaspace::purge(MetadataType mdtype) { get_space_list(mdtype)->purge(get_chunk_manager(mdtype)); } void Metaspace::purge() { MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); purge(NonClassType); if (using_class_space()) { purge(ClassType); } } bool Metaspace::contains(const void* ptr) { if (MetaspaceShared::is_in_shared_metaspace(ptr)) { return true; } return contains_non_shared(ptr); } bool Metaspace::contains_non_shared(const void* ptr) { if (using_class_space() && get_space_list(ClassType)->contains(ptr)) { return true; } return get_space_list(NonClassType)->contains(ptr); } // ClassLoaderMetaspace ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type) : _space_type(type) , _lock(lock) , _vsm(NULL) , _class_vsm(NULL) { initialize(lock, type); } ClassLoaderMetaspace::~ClassLoaderMetaspace() { Metaspace::assert_not_frozen(); DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_deaths)); delete _vsm; if (Metaspace::using_class_space()) { delete _class_vsm; } } void ClassLoaderMetaspace::initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) { Metachunk* chunk = get_initialization_chunk(type, mdtype); if (chunk != NULL) { // Add to this manager's list of chunks in use and make it the current_chunk(). get_space_manager(mdtype)->add_chunk(chunk, true); } } Metachunk* ClassLoaderMetaspace::get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) { size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type); // Get a chunk from the chunk freelist Metachunk* chunk = Metaspace::get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size); if (chunk == NULL) { chunk = Metaspace::get_space_list(mdtype)->get_new_chunk(chunk_word_size, get_space_manager(mdtype)->medium_chunk_bunch()); } return chunk; } void ClassLoaderMetaspace::initialize(Mutex* lock, Metaspace::MetaspaceType type) { Metaspace::verify_global_initialization(); DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_births)); // Allocate SpaceManager for metadata objects. _vsm = new SpaceManager(Metaspace::NonClassType, type, lock); if (Metaspace::using_class_space()) { // Allocate SpaceManager for classes. _class_vsm = new SpaceManager(Metaspace::ClassType, type, lock); } MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); // Allocate chunk for metadata objects initialize_first_chunk(type, Metaspace::NonClassType); // Allocate chunk for class metadata objects if (Metaspace::using_class_space()) { initialize_first_chunk(type, Metaspace::ClassType); } } MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdtype) { Metaspace::assert_not_frozen(); DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_allocs)); // Don't use class_vsm() unless UseCompressedClassPointers is true. if (Metaspace::is_class_space_allocation(mdtype)) { return class_vsm()->allocate(word_size); } else { return vsm()->allocate(word_size); } } MetaWord* ClassLoaderMetaspace::expand_and_allocate(size_t word_size, Metaspace::MetadataType mdtype) { Metaspace::assert_not_frozen(); size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord); assert(delta_bytes > 0, "Must be"); size_t before = 0; size_t after = 0; MetaWord* res; bool incremented; // Each thread increments the HWM at most once. Even if the thread fails to increment // the HWM, an allocation is still attempted. This is because another thread must then // have incremented the HWM and therefore the allocation might still succeed. do { incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before); if (!incremented && SafepointSynchronize::is_at_safepoint()) { // Cannot expand metaspace more. return NULL; } res = allocate(word_size, mdtype); } while (!incremented && res == NULL); if (incremented) { Metaspace::tracer()->report_gc_threshold(before, after, MetaspaceGCThresholdUpdater::ExpandAndAllocate); log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after); } return res; } size_t ClassLoaderMetaspace::allocated_blocks_bytes() const { return (vsm()->used_words() + (Metaspace::using_class_space() ? class_vsm()->used_words() : 0)) * BytesPerWord; } size_t ClassLoaderMetaspace::allocated_chunks_bytes() const { return (vsm()->capacity_words() + (Metaspace::using_class_space() ? class_vsm()->capacity_words() : 0)) * BytesPerWord; } void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) { Metaspace::assert_not_frozen(); assert(!SafepointSynchronize::is_at_safepoint() || Thread::current()->is_VM_thread(), "should be the VM thread"); DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_external_deallocs)); MutexLockerEx ml(vsm()->lock(), Mutex::_no_safepoint_check_flag); if (is_class && Metaspace::using_class_space()) { class_vsm()->deallocate(ptr, word_size); } else { vsm()->deallocate(ptr, word_size); } } size_t ClassLoaderMetaspace::class_chunk_size(size_t word_size) { assert(Metaspace::using_class_space(), "Has to use class space"); return class_vsm()->calc_chunk_size(word_size); } void ClassLoaderMetaspace::print_on(outputStream* out) const { // Print both class virtual space counts and metaspace. if (Verbose) { vsm()->print_on(out); if (Metaspace::using_class_space()) { class_vsm()->print_on(out); } } } void ClassLoaderMetaspace::verify() { vsm()->verify(); if (Metaspace::using_class_space()) { class_vsm()->verify(); } } void ClassLoaderMetaspace::add_to_statistics_locked(ClassLoaderMetaspaceStatistics* out) const { assert_lock_strong(lock()); vsm()->add_to_statistics_locked(&out->nonclass_sm_stats()); if (Metaspace::using_class_space()) { class_vsm()->add_to_statistics_locked(&out->class_sm_stats()); } } void ClassLoaderMetaspace::add_to_statistics(ClassLoaderMetaspaceStatistics* out) const { MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag); add_to_statistics_locked(out); } /////////////// Unit tests /////////////// #ifndef PRODUCT class TestMetaspaceUtilsTest : AllStatic { public: static void test_reserved() { size_t reserved = MetaspaceUtils::reserved_bytes(); assert(reserved > 0, "assert"); size_t committed = MetaspaceUtils::committed_bytes(); assert(committed <= reserved, "assert"); size_t reserved_metadata = MetaspaceUtils::reserved_bytes(Metaspace::NonClassType); assert(reserved_metadata > 0, "assert"); assert(reserved_metadata <= reserved, "assert"); if (UseCompressedClassPointers) { size_t reserved_class = MetaspaceUtils::reserved_bytes(Metaspace::ClassType); assert(reserved_class > 0, "assert"); assert(reserved_class < reserved, "assert"); } } static void test_committed() { size_t committed = MetaspaceUtils::committed_bytes(); assert(committed > 0, "assert"); size_t reserved = MetaspaceUtils::reserved_bytes(); assert(committed <= reserved, "assert"); size_t committed_metadata = MetaspaceUtils::committed_bytes(Metaspace::NonClassType); assert(committed_metadata > 0, "assert"); assert(committed_metadata <= committed, "assert"); if (UseCompressedClassPointers) { size_t committed_class = MetaspaceUtils::committed_bytes(Metaspace::ClassType); assert(committed_class > 0, "assert"); assert(committed_class < committed, "assert"); } } static void test_virtual_space_list_large_chunk() { VirtualSpaceList* vs_list = new VirtualSpaceList(os::vm_allocation_granularity()); MutexLockerEx cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag); // A size larger than VirtualSpaceSize (256k) and add one page to make it _not_ be // vm_allocation_granularity aligned on Windows. size_t large_size = (size_t)(2*256*K + (os::vm_page_size()/BytesPerWord)); large_size += (os::vm_page_size()/BytesPerWord); vs_list->get_new_chunk(large_size, 0); } static void test() { test_reserved(); test_committed(); test_virtual_space_list_large_chunk(); } }; void TestMetaspaceUtils_test() { TestMetaspaceUtilsTest::test(); } #endif // !PRODUCT struct chunkmanager_statistics_t { int num_specialized_chunks; int num_small_chunks; int num_medium_chunks; int num_humongous_chunks; }; extern void test_metaspace_retrieve_chunkmanager_statistics(Metaspace::MetadataType mdType, chunkmanager_statistics_t* out) { ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(mdType); ChunkManagerStatistics stat; chunk_manager->collect_statistics(&stat); out->num_specialized_chunks = (int)stat.chunk_stats(SpecializedIndex).num(); out->num_small_chunks = (int)stat.chunk_stats(SmallIndex).num(); out->num_medium_chunks = (int)stat.chunk_stats(MediumIndex).num(); out->num_humongous_chunks = (int)stat.chunk_stats(HumongousIndex).num(); } struct chunk_geometry_t { size_t specialized_chunk_word_size; size_t small_chunk_word_size; size_t medium_chunk_word_size; }; extern void test_metaspace_retrieve_chunk_geometry(Metaspace::MetadataType mdType, chunk_geometry_t* out) { if (mdType == Metaspace::NonClassType) { out->specialized_chunk_word_size = SpecializedChunk; out->small_chunk_word_size = SmallChunk; out->medium_chunk_word_size = MediumChunk; } else { out->specialized_chunk_word_size = ClassSpecializedChunk; out->small_chunk_word_size = ClassSmallChunk; out->medium_chunk_word_size = ClassMediumChunk; } }