688 lines
25 KiB
C++
688 lines
25 KiB
C++
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/*
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* Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*
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*/
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#include "precompiled.hpp"
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#include "classfile/stringTable.hpp"
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#include "classfile/systemDictionary.hpp"
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#include "code/codeCache.hpp"
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#include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
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#include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp"
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#include "gc_implementation/parallelScavenge/psMarkSweep.hpp"
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#include "gc_implementation/parallelScavenge/psMarkSweepDecorator.hpp"
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#include "gc_implementation/parallelScavenge/psOldGen.hpp"
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#include "gc_implementation/parallelScavenge/psScavenge.hpp"
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#include "gc_implementation/parallelScavenge/psYoungGen.hpp"
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#include "gc_implementation/shared/gcHeapSummary.hpp"
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#include "gc_implementation/shared/gcTimer.hpp"
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#include "gc_implementation/shared/gcTrace.hpp"
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#include "gc_implementation/shared/gcTraceTime.hpp"
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#include "gc_implementation/shared/isGCActiveMark.hpp"
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#include "gc_implementation/shared/markSweep.hpp"
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#include "gc_implementation/shared/spaceDecorator.hpp"
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#include "gc_interface/gcCause.hpp"
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#include "memory/gcLocker.inline.hpp"
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#include "memory/referencePolicy.hpp"
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#include "memory/referenceProcessor.hpp"
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#include "oops/oop.inline.hpp"
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#include "runtime/biasedLocking.hpp"
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#include "runtime/fprofiler.hpp"
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#include "runtime/safepoint.hpp"
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#include "runtime/vmThread.hpp"
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#include "services/management.hpp"
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#include "services/memoryService.hpp"
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#include "utilities/events.hpp"
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#include "utilities/stack.inline.hpp"
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PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
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elapsedTimer PSMarkSweep::_accumulated_time;
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jlong PSMarkSweep::_time_of_last_gc = 0;
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CollectorCounters* PSMarkSweep::_counters = NULL;
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void PSMarkSweep::initialize() {
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MemRegion mr = Universe::heap()->reserved_region();
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_ref_processor = new ReferenceProcessor(mr); // a vanilla ref proc
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_counters = new CollectorCounters("PSMarkSweep", 1);
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}
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// This method contains all heap specific policy for invoking mark sweep.
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// PSMarkSweep::invoke_no_policy() will only attempt to mark-sweep-compact
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// the heap. It will do nothing further. If we need to bail out for policy
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// reasons, scavenge before full gc, or any other specialized behavior, it
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// needs to be added here.
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//
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// Note that this method should only be called from the vm_thread while
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// at a safepoint!
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//
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// Note that the all_soft_refs_clear flag in the collector policy
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// may be true because this method can be called without intervening
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// activity. For example when the heap space is tight and full measure
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// are being taken to free space.
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void PSMarkSweep::invoke(bool maximum_heap_compaction) {
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assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
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assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
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assert(!Universe::heap()->is_gc_active(), "not reentrant");
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ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
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GCCause::Cause gc_cause = heap->gc_cause();
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PSAdaptiveSizePolicy* policy = heap->size_policy();
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IsGCActiveMark mark;
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if (ScavengeBeforeFullGC) {
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PSScavenge::invoke_no_policy();
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}
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const bool clear_all_soft_refs =
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heap->collector_policy()->should_clear_all_soft_refs();
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uint count = maximum_heap_compaction ? 1 : MarkSweepAlwaysCompactCount;
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UIntFlagSetting flag_setting(MarkSweepAlwaysCompactCount, count);
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PSMarkSweep::invoke_no_policy(clear_all_soft_refs || maximum_heap_compaction);
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}
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// This method contains no policy. You should probably
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// be calling invoke() instead.
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bool PSMarkSweep::invoke_no_policy(bool clear_all_softrefs) {
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assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
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assert(ref_processor() != NULL, "Sanity");
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if (GC_locker::check_active_before_gc()) {
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return false;
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}
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ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
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assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
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GCCause::Cause gc_cause = heap->gc_cause();
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_gc_timer->register_gc_start();
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_gc_tracer->report_gc_start(gc_cause, _gc_timer->gc_start());
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PSAdaptiveSizePolicy* size_policy = heap->size_policy();
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// The scope of casr should end after code that can change
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// CollectorPolicy::_should_clear_all_soft_refs.
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ClearedAllSoftRefs casr(clear_all_softrefs, heap->collector_policy());
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PSYoungGen* young_gen = heap->young_gen();
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PSOldGen* old_gen = heap->old_gen();
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// Increment the invocation count
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heap->increment_total_collections(true /* full */);
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// Save information needed to minimize mangling
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heap->record_gen_tops_before_GC();
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// We need to track unique mark sweep invocations as well.
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_total_invocations++;
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AdaptiveSizePolicyOutput(size_policy, heap->total_collections());
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heap->print_heap_before_gc();
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heap->trace_heap_before_gc(_gc_tracer);
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// Fill in TLABs
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heap->accumulate_statistics_all_tlabs();
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heap->ensure_parsability(true); // retire TLABs
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if (VerifyBeforeGC && heap->total_collections() >= VerifyGCStartAt) {
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HandleMark hm; // Discard invalid handles created during verification
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Universe::verify(" VerifyBeforeGC:");
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}
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// Verify object start arrays
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if (VerifyObjectStartArray &&
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VerifyBeforeGC) {
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old_gen->verify_object_start_array();
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}
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heap->pre_full_gc_dump(_gc_timer);
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// Filled in below to track the state of the young gen after the collection.
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bool eden_empty;
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bool survivors_empty;
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bool young_gen_empty;
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{
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HandleMark hm;
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TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty);
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GCTraceTime t1(GCCauseString("Full GC", gc_cause), PrintGC, !PrintGCDetails, NULL, _gc_tracer->gc_id());
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TraceCollectorStats tcs(counters());
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TraceMemoryManagerStats tms(true /* Full GC */,gc_cause);
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if (TraceOldGenTime) accumulated_time()->start();
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// Let the size policy know we're starting
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size_policy->major_collection_begin();
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CodeCache::gc_prologue();
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BiasedLocking::preserve_marks();
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// Capture heap size before collection for printing.
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size_t prev_used = heap->used();
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// Capture metadata size before collection for sizing.
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size_t metadata_prev_used = MetaspaceAux::used_bytes();
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// For PrintGCDetails
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size_t old_gen_prev_used = old_gen->used_in_bytes();
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size_t young_gen_prev_used = young_gen->used_in_bytes();
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allocate_stacks();
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COMPILER2_PRESENT(DerivedPointerTable::clear());
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ref_processor()->enable_discovery();
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ref_processor()->setup_policy(clear_all_softrefs);
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mark_sweep_phase1(clear_all_softrefs);
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mark_sweep_phase2();
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// Don't add any more derived pointers during phase3
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COMPILER2_PRESENT(assert(DerivedPointerTable::is_active(), "Sanity"));
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COMPILER2_PRESENT(DerivedPointerTable::set_active(false));
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mark_sweep_phase3();
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mark_sweep_phase4();
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restore_marks();
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deallocate_stacks();
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if (ZapUnusedHeapArea) {
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// Do a complete mangle (top to end) because the usage for
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// scratch does not maintain a top pointer.
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young_gen->to_space()->mangle_unused_area_complete();
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}
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eden_empty = young_gen->eden_space()->is_empty();
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if (!eden_empty) {
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eden_empty = absorb_live_data_from_eden(size_policy, young_gen, old_gen);
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}
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// Update heap occupancy information which is used as
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// input to soft ref clearing policy at the next gc.
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Universe::update_heap_info_at_gc();
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survivors_empty = young_gen->from_space()->is_empty() &&
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young_gen->to_space()->is_empty();
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young_gen_empty = eden_empty && survivors_empty;
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BarrierSet* bs = heap->barrier_set();
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if (bs->is_a(BarrierSet::ModRef)) {
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ModRefBarrierSet* modBS = (ModRefBarrierSet*)bs;
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MemRegion old_mr = heap->old_gen()->reserved();
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if (young_gen_empty) {
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modBS->clear(MemRegion(old_mr.start(), old_mr.end()));
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} else {
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modBS->invalidate(MemRegion(old_mr.start(), old_mr.end()));
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}
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}
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// Delete metaspaces for unloaded class loaders and clean up loader_data graph
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ClassLoaderDataGraph::purge();
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MetaspaceAux::verify_metrics();
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BiasedLocking::restore_marks();
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CodeCache::gc_epilogue();
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JvmtiExport::gc_epilogue();
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COMPILER2_PRESENT(DerivedPointerTable::update_pointers());
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ref_processor()->enqueue_discovered_references(NULL);
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// Update time of last GC
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reset_millis_since_last_gc();
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// Let the size policy know we're done
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size_policy->major_collection_end(old_gen->used_in_bytes(), gc_cause);
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if (UseAdaptiveSizePolicy) {
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if (PrintAdaptiveSizePolicy) {
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gclog_or_tty->print("AdaptiveSizeStart: ");
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gclog_or_tty->stamp();
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gclog_or_tty->print_cr(" collection: %d ",
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heap->total_collections());
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if (Verbose) {
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gclog_or_tty->print("old_gen_capacity: " SIZE_FORMAT
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" young_gen_capacity: " SIZE_FORMAT,
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old_gen->capacity_in_bytes(), young_gen->capacity_in_bytes());
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}
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}
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// Don't check if the size_policy is ready here. Let
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// the size_policy check that internally.
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if (UseAdaptiveGenerationSizePolicyAtMajorCollection &&
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((gc_cause != GCCause::_java_lang_system_gc) ||
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UseAdaptiveSizePolicyWithSystemGC)) {
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// Swap the survivor spaces if from_space is empty. The
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// resize_young_gen() called below is normally used after
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// a successful young GC and swapping of survivor spaces;
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// otherwise, it will fail to resize the young gen with
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// the current implementation.
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if (young_gen->from_space()->is_empty()) {
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young_gen->from_space()->clear(SpaceDecorator::Mangle);
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young_gen->swap_spaces();
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}
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// Calculate optimal free space amounts
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assert(young_gen->max_size() >
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young_gen->from_space()->capacity_in_bytes() +
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young_gen->to_space()->capacity_in_bytes(),
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"Sizes of space in young gen are out-of-bounds");
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size_t young_live = young_gen->used_in_bytes();
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size_t eden_live = young_gen->eden_space()->used_in_bytes();
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size_t old_live = old_gen->used_in_bytes();
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size_t cur_eden = young_gen->eden_space()->capacity_in_bytes();
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size_t max_old_gen_size = old_gen->max_gen_size();
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size_t max_eden_size = young_gen->max_size() -
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young_gen->from_space()->capacity_in_bytes() -
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young_gen->to_space()->capacity_in_bytes();
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// Used for diagnostics
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size_policy->clear_generation_free_space_flags();
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size_policy->compute_generations_free_space(young_live,
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eden_live,
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old_live,
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cur_eden,
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max_old_gen_size,
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max_eden_size,
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true /* full gc*/);
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size_policy->check_gc_overhead_limit(young_live,
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eden_live,
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max_old_gen_size,
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max_eden_size,
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true /* full gc*/,
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gc_cause,
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heap->collector_policy());
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size_policy->decay_supplemental_growth(true /* full gc*/);
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heap->resize_old_gen(size_policy->calculated_old_free_size_in_bytes());
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heap->resize_young_gen(size_policy->calculated_eden_size_in_bytes(),
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size_policy->calculated_survivor_size_in_bytes());
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}
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if (PrintAdaptiveSizePolicy) {
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gclog_or_tty->print_cr("AdaptiveSizeStop: collection: %d ",
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heap->total_collections());
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}
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}
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if (UsePerfData) {
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heap->gc_policy_counters()->update_counters();
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heap->gc_policy_counters()->update_old_capacity(
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old_gen->capacity_in_bytes());
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heap->gc_policy_counters()->update_young_capacity(
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young_gen->capacity_in_bytes());
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}
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heap->resize_all_tlabs();
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// We collected the heap, recalculate the metaspace capacity
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MetaspaceGC::compute_new_size();
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if (TraceOldGenTime) accumulated_time()->stop();
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if (PrintGC) {
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if (PrintGCDetails) {
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// Don't print a GC timestamp here. This is after the GC so
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// would be confusing.
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young_gen->print_used_change(young_gen_prev_used);
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old_gen->print_used_change(old_gen_prev_used);
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}
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heap->print_heap_change(prev_used);
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if (PrintGCDetails) {
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MetaspaceAux::print_metaspace_change(metadata_prev_used);
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}
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}
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// Track memory usage and detect low memory
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MemoryService::track_memory_usage();
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heap->update_counters();
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}
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if (VerifyAfterGC && heap->total_collections() >= VerifyGCStartAt) {
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HandleMark hm; // Discard invalid handles created during verification
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Universe::verify(" VerifyAfterGC:");
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}
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// Re-verify object start arrays
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if (VerifyObjectStartArray &&
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VerifyAfterGC) {
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old_gen->verify_object_start_array();
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}
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if (ZapUnusedHeapArea) {
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old_gen->object_space()->check_mangled_unused_area_complete();
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}
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NOT_PRODUCT(ref_processor()->verify_no_references_recorded());
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heap->print_heap_after_gc();
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heap->trace_heap_after_gc(_gc_tracer);
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heap->post_full_gc_dump(_gc_timer);
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#ifdef TRACESPINNING
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ParallelTaskTerminator::print_termination_counts();
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#endif
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_gc_timer->register_gc_end();
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_gc_tracer->report_gc_end(_gc_timer->gc_end(), _gc_timer->time_partitions());
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return true;
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}
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bool PSMarkSweep::absorb_live_data_from_eden(PSAdaptiveSizePolicy* size_policy,
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PSYoungGen* young_gen,
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PSOldGen* old_gen) {
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MutableSpace* const eden_space = young_gen->eden_space();
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assert(!eden_space->is_empty(), "eden must be non-empty");
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assert(young_gen->virtual_space()->alignment() ==
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old_gen->virtual_space()->alignment(), "alignments do not match");
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if (!(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary)) {
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return false;
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}
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// Both generations must be completely committed.
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if (young_gen->virtual_space()->uncommitted_size() != 0) {
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return false;
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}
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if (old_gen->virtual_space()->uncommitted_size() != 0) {
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return false;
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}
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// Figure out how much to take from eden. Include the average amount promoted
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// in the total; otherwise the next young gen GC will simply bail out to a
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// full GC.
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const size_t alignment = old_gen->virtual_space()->alignment();
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const size_t eden_used = eden_space->used_in_bytes();
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const size_t promoted = (size_t)size_policy->avg_promoted()->padded_average();
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const size_t absorb_size = align_size_up(eden_used + promoted, alignment);
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const size_t eden_capacity = eden_space->capacity_in_bytes();
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if (absorb_size >= eden_capacity) {
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return false; // Must leave some space in eden.
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}
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const size_t new_young_size = young_gen->capacity_in_bytes() - absorb_size;
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if (new_young_size < young_gen->min_gen_size()) {
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return false; // Respect young gen minimum size.
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}
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if (TraceAdaptiveGCBoundary && Verbose) {
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gclog_or_tty->print(" absorbing " SIZE_FORMAT "K: "
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"eden " SIZE_FORMAT "K->" SIZE_FORMAT "K "
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"from " SIZE_FORMAT "K, to " SIZE_FORMAT "K "
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"young_gen " SIZE_FORMAT "K->" SIZE_FORMAT "K ",
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absorb_size / K,
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eden_capacity / K, (eden_capacity - absorb_size) / K,
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young_gen->from_space()->used_in_bytes() / K,
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young_gen->to_space()->used_in_bytes() / K,
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young_gen->capacity_in_bytes() / K, new_young_size / K);
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}
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// Fill the unused part of the old gen.
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MutableSpace* const old_space = old_gen->object_space();
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HeapWord* const unused_start = old_space->top();
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size_t const unused_words = pointer_delta(old_space->end(), unused_start);
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if (unused_words > 0) {
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if (unused_words < CollectedHeap::min_fill_size()) {
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return false; // If the old gen cannot be filled, must give up.
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}
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CollectedHeap::fill_with_objects(unused_start, unused_words);
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}
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// Take the live data from eden and set both top and end in the old gen to
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// eden top. (Need to set end because reset_after_change() mangles the region
|
|
// from end to virtual_space->high() in debug builds).
|
|
HeapWord* const new_top = eden_space->top();
|
|
old_gen->virtual_space()->expand_into(young_gen->virtual_space(),
|
|
absorb_size);
|
|
young_gen->reset_after_change();
|
|
old_space->set_top(new_top);
|
|
old_space->set_end(new_top);
|
|
old_gen->reset_after_change();
|
|
|
|
// Update the object start array for the filler object and the data from eden.
|
|
ObjectStartArray* const start_array = old_gen->start_array();
|
|
for (HeapWord* p = unused_start; p < new_top; p += oop(p)->size()) {
|
|
start_array->allocate_block(p);
|
|
}
|
|
|
|
// Could update the promoted average here, but it is not typically updated at
|
|
// full GCs and the value to use is unclear. Something like
|
|
//
|
|
// cur_promoted_avg + absorb_size / number_of_scavenges_since_last_full_gc.
|
|
|
|
size_policy->set_bytes_absorbed_from_eden(absorb_size);
|
|
return true;
|
|
}
|
|
|
|
void PSMarkSweep::allocate_stacks() {
|
|
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
|
|
|
|
PSYoungGen* young_gen = heap->young_gen();
|
|
|
|
MutableSpace* to_space = young_gen->to_space();
|
|
_preserved_marks = (PreservedMark*)to_space->top();
|
|
_preserved_count = 0;
|
|
|
|
// We want to calculate the size in bytes first.
|
|
_preserved_count_max = pointer_delta(to_space->end(), to_space->top(), sizeof(jbyte));
|
|
// Now divide by the size of a PreservedMark
|
|
_preserved_count_max /= sizeof(PreservedMark);
|
|
}
|
|
|
|
|
|
void PSMarkSweep::deallocate_stacks() {
|
|
_preserved_mark_stack.clear(true);
|
|
_preserved_oop_stack.clear(true);
|
|
_marking_stack.clear();
|
|
_objarray_stack.clear(true);
|
|
}
|
|
|
|
void PSMarkSweep::mark_sweep_phase1(bool clear_all_softrefs) {
|
|
// Recursively traverse all live objects and mark them
|
|
GCTraceTime tm("phase 1", PrintGCDetails && Verbose, true, _gc_timer, _gc_tracer->gc_id());
|
|
trace(" 1");
|
|
|
|
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
|
|
|
|
// Need to clear claim bits before the tracing starts.
|
|
ClassLoaderDataGraph::clear_claimed_marks();
|
|
|
|
// General strong roots.
|
|
{
|
|
ParallelScavengeHeap::ParStrongRootsScope psrs;
|
|
Universe::oops_do(mark_and_push_closure());
|
|
JNIHandles::oops_do(mark_and_push_closure()); // Global (strong) JNI handles
|
|
CLDToOopClosure mark_and_push_from_cld(mark_and_push_closure());
|
|
MarkingCodeBlobClosure each_active_code_blob(mark_and_push_closure(), !CodeBlobToOopClosure::FixRelocations);
|
|
Threads::oops_do(mark_and_push_closure(), &mark_and_push_from_cld, &each_active_code_blob);
|
|
ObjectSynchronizer::oops_do(mark_and_push_closure());
|
|
FlatProfiler::oops_do(mark_and_push_closure());
|
|
Management::oops_do(mark_and_push_closure());
|
|
JvmtiExport::oops_do(mark_and_push_closure());
|
|
SystemDictionary::always_strong_oops_do(mark_and_push_closure());
|
|
ClassLoaderDataGraph::always_strong_cld_do(follow_cld_closure());
|
|
// Do not treat nmethods as strong roots for mark/sweep, since we can unload them.
|
|
//CodeCache::scavenge_root_nmethods_do(CodeBlobToOopClosure(mark_and_push_closure()));
|
|
}
|
|
|
|
// Flush marking stack.
|
|
follow_stack();
|
|
|
|
// Process reference objects found during marking
|
|
{
|
|
ref_processor()->setup_policy(clear_all_softrefs);
|
|
const ReferenceProcessorStats& stats =
|
|
ref_processor()->process_discovered_references(
|
|
is_alive_closure(), mark_and_push_closure(), follow_stack_closure(), NULL, _gc_timer, _gc_tracer->gc_id());
|
|
gc_tracer()->report_gc_reference_stats(stats);
|
|
}
|
|
|
|
// This is the point where the entire marking should have completed.
|
|
assert(_marking_stack.is_empty(), "Marking should have completed");
|
|
|
|
// Unload classes and purge the SystemDictionary.
|
|
bool purged_class = SystemDictionary::do_unloading(is_alive_closure());
|
|
|
|
// Unload nmethods.
|
|
CodeCache::do_unloading(is_alive_closure(), purged_class);
|
|
|
|
// Prune dead klasses from subklass/sibling/implementor lists.
|
|
Klass::clean_weak_klass_links(is_alive_closure());
|
|
|
|
// Delete entries for dead interned strings.
|
|
StringTable::unlink(is_alive_closure());
|
|
|
|
// Clean up unreferenced symbols in symbol table.
|
|
SymbolTable::unlink();
|
|
_gc_tracer->report_object_count_after_gc(is_alive_closure());
|
|
}
|
|
|
|
|
|
void PSMarkSweep::mark_sweep_phase2() {
|
|
GCTraceTime tm("phase 2", PrintGCDetails && Verbose, true, _gc_timer, _gc_tracer->gc_id());
|
|
trace("2");
|
|
|
|
// Now all live objects are marked, compute the new object addresses.
|
|
|
|
// It is not required that we traverse spaces in the same order in
|
|
// phase2, phase3 and phase4, but the ValidateMarkSweep live oops
|
|
// tracking expects us to do so. See comment under phase4.
|
|
|
|
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
|
|
|
|
PSOldGen* old_gen = heap->old_gen();
|
|
|
|
// Begin compacting into the old gen
|
|
PSMarkSweepDecorator::set_destination_decorator_tenured();
|
|
|
|
// This will also compact the young gen spaces.
|
|
old_gen->precompact();
|
|
}
|
|
|
|
// This should be moved to the shared markSweep code!
|
|
class PSAlwaysTrueClosure: public BoolObjectClosure {
|
|
public:
|
|
bool do_object_b(oop p) { return true; }
|
|
};
|
|
static PSAlwaysTrueClosure always_true;
|
|
|
|
void PSMarkSweep::mark_sweep_phase3() {
|
|
// Adjust the pointers to reflect the new locations
|
|
GCTraceTime tm("phase 3", PrintGCDetails && Verbose, true, _gc_timer, _gc_tracer->gc_id());
|
|
trace("3");
|
|
|
|
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
|
|
|
|
PSYoungGen* young_gen = heap->young_gen();
|
|
PSOldGen* old_gen = heap->old_gen();
|
|
|
|
// Need to clear claim bits before the tracing starts.
|
|
ClassLoaderDataGraph::clear_claimed_marks();
|
|
|
|
// General strong roots.
|
|
Universe::oops_do(adjust_pointer_closure());
|
|
JNIHandles::oops_do(adjust_pointer_closure()); // Global (strong) JNI handles
|
|
CLDToOopClosure adjust_from_cld(adjust_pointer_closure());
|
|
Threads::oops_do(adjust_pointer_closure(), &adjust_from_cld, NULL);
|
|
ObjectSynchronizer::oops_do(adjust_pointer_closure());
|
|
FlatProfiler::oops_do(adjust_pointer_closure());
|
|
Management::oops_do(adjust_pointer_closure());
|
|
JvmtiExport::oops_do(adjust_pointer_closure());
|
|
SystemDictionary::oops_do(adjust_pointer_closure());
|
|
ClassLoaderDataGraph::cld_do(adjust_cld_closure());
|
|
|
|
// Now adjust pointers in remaining weak roots. (All of which should
|
|
// have been cleared if they pointed to non-surviving objects.)
|
|
// Global (weak) JNI handles
|
|
JNIHandles::weak_oops_do(&always_true, adjust_pointer_closure());
|
|
|
|
CodeBlobToOopClosure adjust_from_blobs(adjust_pointer_closure(), CodeBlobToOopClosure::FixRelocations);
|
|
CodeCache::blobs_do(&adjust_from_blobs);
|
|
StringTable::oops_do(adjust_pointer_closure());
|
|
ref_processor()->weak_oops_do(adjust_pointer_closure());
|
|
PSScavenge::reference_processor()->weak_oops_do(adjust_pointer_closure());
|
|
|
|
adjust_marks();
|
|
|
|
young_gen->adjust_pointers();
|
|
old_gen->adjust_pointers();
|
|
}
|
|
|
|
void PSMarkSweep::mark_sweep_phase4() {
|
|
EventMark m("4 compact heap");
|
|
GCTraceTime tm("phase 4", PrintGCDetails && Verbose, true, _gc_timer, _gc_tracer->gc_id());
|
|
trace("4");
|
|
|
|
// All pointers are now adjusted, move objects accordingly
|
|
|
|
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
|
|
|
|
PSYoungGen* young_gen = heap->young_gen();
|
|
PSOldGen* old_gen = heap->old_gen();
|
|
|
|
old_gen->compact();
|
|
young_gen->compact();
|
|
}
|
|
|
|
jlong PSMarkSweep::millis_since_last_gc() {
|
|
// We need a monotonically non-decreasing time in ms but
|
|
// os::javaTimeMillis() does not guarantee monotonicity.
|
|
jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
|
|
jlong ret_val = now - _time_of_last_gc;
|
|
// XXX See note in genCollectedHeap::millis_since_last_gc().
|
|
if (ret_val < 0) {
|
|
NOT_PRODUCT(warning("time warp: "INT64_FORMAT, ret_val);)
|
|
return 0;
|
|
}
|
|
return ret_val;
|
|
}
|
|
|
|
void PSMarkSweep::reset_millis_since_last_gc() {
|
|
// We need a monotonically non-decreasing time in ms but
|
|
// os::javaTimeMillis() does not guarantee monotonicity.
|
|
_time_of_last_gc = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
|
|
}
|