1044 
1045   // Update heap occupancy information which is used as input to the soft ref
1046   // clearing policy at the next gc.
1047   Universe::update_heap_info_at_gc();
1048 
1049   bool young_gen_empty = eden_empty && from_space->is_empty() &&
1050     to_space->is_empty();
1051 
1052   PSCardTable* ct = heap->card_table();
1053   MemRegion old_mr = heap->old_gen()->reserved();
1054   if (young_gen_empty) {
1055     ct->clear(MemRegion(old_mr.start(), old_mr.end()));
1056   } else {
1057     ct->invalidate(MemRegion(old_mr.start(), old_mr.end()));
1058   }
1059 
1060   // Delete metaspaces for unloaded class loaders and clean up loader_data graph
1061   ClassLoaderDataGraph::purge();
1062   MetaspaceUtils::verify_metrics();
1063 
1064   CodeCache::gc_epilogue();
1065   JvmtiExport::gc_epilogue();
1066 
1067 #if COMPILER2_OR_JVMCI
1068   DerivedPointerTable::update_pointers();
1069 #endif
1070 
1071   if (ZapUnusedHeapArea) {
1072     heap->gen_mangle_unused_area();
1073   }
1074 
1075   // Update time of last GC
1076   reset_millis_since_last_gc();
1077 }
1078 
1079 HeapWord*
1080 PSParallelCompact::compute_dense_prefix_via_density(const SpaceId id,
1081                                                     bool maximum_compaction)
1082 {
1083   const size_t region_size = ParallelCompactData::RegionSize;
1084   const ParallelCompactData& sd = summary_data();

1790 
1791     // Set the number of GC threads to be used in this collection
1792     gc_task_manager()->set_active_gang();
1793     gc_task_manager()->task_idle_workers();
1794 
1795     GCTraceCPUTime tcpu;
1796     GCTraceTime(Info, gc) tm("Pause Full", NULL, gc_cause, true);
1797 
1798     heap->pre_full_gc_dump(&_gc_timer);
1799 
1800     TraceCollectorStats tcs(counters());
1801     TraceMemoryManagerStats tms(heap->old_gc_manager(), gc_cause);
1802 
1803     if (log_is_enabled(Debug, gc, heap, exit)) {
1804       accumulated_time()->start();
1805     }
1806 
1807     // Let the size policy know we're starting
1808     size_policy->major_collection_begin();
1809 
1810     CodeCache::gc_prologue();
1811 
1812 #if COMPILER2_OR_JVMCI
1813     DerivedPointerTable::clear();
1814 #endif
1815 
1816     ref_processor()->enable_discovery();
1817     ref_processor()->setup_policy(maximum_heap_compaction);
1818 
1819     bool marked_for_unloading = false;
1820 
1821     marking_start.update();
1822     marking_phase(vmthread_cm, maximum_heap_compaction, &_gc_tracer);
1823 
1824     bool max_on_system_gc = UseMaximumCompactionOnSystemGC
1825       && GCCause::is_user_requested_gc(gc_cause);
1826     summary_phase(vmthread_cm, maximum_heap_compaction || max_on_system_gc);
1827 
1828 #if COMPILER2_OR_JVMCI
1829     assert(DerivedPointerTable::is_active(), "Sanity");
1830     DerivedPointerTable::set_active(false);

1044 
1045   // Update heap occupancy information which is used as input to the soft ref
1046   // clearing policy at the next gc.
1047   Universe::update_heap_info_at_gc();
1048 
1049   bool young_gen_empty = eden_empty && from_space->is_empty() &&
1050     to_space->is_empty();
1051 
1052   PSCardTable* ct = heap->card_table();
1053   MemRegion old_mr = heap->old_gen()->reserved();
1054   if (young_gen_empty) {
1055     ct->clear(MemRegion(old_mr.start(), old_mr.end()));
1056   } else {
1057     ct->invalidate(MemRegion(old_mr.start(), old_mr.end()));
1058   }
1059 
1060   // Delete metaspaces for unloaded class loaders and clean up loader_data graph
1061   ClassLoaderDataGraph::purge();
1062   MetaspaceUtils::verify_metrics();
1063 

1064   JvmtiExport::gc_epilogue();
1065 
1066 #if COMPILER2_OR_JVMCI
1067   DerivedPointerTable::update_pointers();
1068 #endif
1069 
1070   if (ZapUnusedHeapArea) {
1071     heap->gen_mangle_unused_area();
1072   }
1073 
1074   // Update time of last GC
1075   reset_millis_since_last_gc();
1076 }
1077 
1078 HeapWord*
1079 PSParallelCompact::compute_dense_prefix_via_density(const SpaceId id,
1080                                                     bool maximum_compaction)
1081 {
1082   const size_t region_size = ParallelCompactData::RegionSize;
1083   const ParallelCompactData& sd = summary_data();

1789 
1790     // Set the number of GC threads to be used in this collection
1791     gc_task_manager()->set_active_gang();
1792     gc_task_manager()->task_idle_workers();
1793 
1794     GCTraceCPUTime tcpu;
1795     GCTraceTime(Info, gc) tm("Pause Full", NULL, gc_cause, true);
1796 
1797     heap->pre_full_gc_dump(&_gc_timer);
1798 
1799     TraceCollectorStats tcs(counters());
1800     TraceMemoryManagerStats tms(heap->old_gc_manager(), gc_cause);
1801 
1802     if (log_is_enabled(Debug, gc, heap, exit)) {
1803       accumulated_time()->start();
1804     }
1805 
1806     // Let the size policy know we're starting
1807     size_policy->major_collection_begin();
1808 
1809     heap->prune_nmethods();
1810 
1811 #if COMPILER2_OR_JVMCI
1812     DerivedPointerTable::clear();
1813 #endif
1814 
1815     ref_processor()->enable_discovery();
1816     ref_processor()->setup_policy(maximum_heap_compaction);
1817 
1818     bool marked_for_unloading = false;
1819 
1820     marking_start.update();
1821     marking_phase(vmthread_cm, maximum_heap_compaction, &_gc_tracer);
1822 
1823     bool max_on_system_gc = UseMaximumCompactionOnSystemGC
1824       && GCCause::is_user_requested_gc(gc_cause);
1825     summary_phase(vmthread_cm, maximum_heap_compaction || max_on_system_gc);
1826 
1827 #if COMPILER2_OR_JVMCI
1828     assert(DerivedPointerTable::is_active(), "Sanity");
1829     DerivedPointerTable::set_active(false);