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8034842: Parallelize the Free CSet phase in G1

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Reviewed-by: jmasa, ehelin
This commit is contained in:
Thomas Schatzl 2016-07-19 10:31:41 +02:00
parent c0e5b2646f
commit ada5ab192f
10 changed files with 297 additions and 144 deletions
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360
hotspot/src/share/vm/gc/g1/g1CollectedHeap.cpp
View File

@ -4524,7 +4524,8 @@ void G1CollectedHeap::record_obj_copy_mem_stats() {
void G1CollectedHeap::free_region(HeapRegion* hr,
FreeRegionList* free_list,
bool par,
bool skip_remset,
bool skip_hot_card_cache,
bool locked) {
assert(!hr->is_free(), "the region should not be free");
assert(!hr->is_empty(), "the region should not be empty");
@ -4539,20 +4540,20 @@ void G1CollectedHeap::free_region(HeapRegion* hr,
// Clear the card counts for this region.
// Note: we only need to do this if the region is not young
// (since we don't refine cards in young regions).
if (!hr->is_young()) {
if (!skip_hot_card_cache && !hr->is_young()) {
_hot_card_cache->reset_card_counts(hr);
}
hr->hr_clear(par, true /* clear_space */, locked /* locked */);
hr->hr_clear(skip_remset, true /* clear_space */, locked /* locked */);
free_list->add_ordered(hr);
}
void G1CollectedHeap::free_humongous_region(HeapRegion* hr,
FreeRegionList* free_list,
bool par) {
bool skip_remset) {
assert(hr->is_humongous(), "this is only for humongous regions");
assert(free_list != NULL, "pre-condition");
hr->clear_humongous();
free_region(hr, free_list, par);
free_region(hr, free_list, skip_remset);
}
void G1CollectedHeap::remove_from_old_sets(const uint old_regions_removed,
@ -4600,137 +4601,280 @@ void G1CollectedHeap::scrub_rem_set() {
workers()->run_task(&g1_par_scrub_rs_task);
}
class G1FreeCollectionSetClosure : public HeapRegionClosure {
class G1FreeCollectionSetTask : public AbstractGangTask {
private:
// Closure applied to all regions in the collection set to do work that needs to
// be done serially in a single thread.
class G1SerialFreeCollectionSetClosure : public HeapRegionClosure {
private:
EvacuationInfo* _evacuation_info;
const size_t* _surviving_young_words;
// Bytes used in successfully evacuated regions before the evacuation.
size_t _before_used_bytes;
// Bytes used in unsucessfully evacuated regions before the evacuation
size_t _after_used_bytes;
size_t _bytes_allocated_in_old_since_last_gc;
size_t _failure_used_words;
size_t _failure_waste_words;
FreeRegionList _local_free_list;
public:
G1SerialFreeCollectionSetClosure(EvacuationInfo* evacuation_info, const size_t* surviving_young_words) :
HeapRegionClosure(),
_evacuation_info(evacuation_info),
_surviving_young_words(surviving_young_words),
_before_used_bytes(0),
_after_used_bytes(0),
_bytes_allocated_in_old_since_last_gc(0),
_failure_used_words(0),
_failure_waste_words(0),
_local_free_list("Local Region List for CSet Freeing") {
}
virtual bool doHeapRegion(HeapRegion* r) {
G1CollectedHeap* g1h = G1CollectedHeap::heap();
assert(r->in_collection_set(), "Region %u should be in collection set.", r->hrm_index());
g1h->clear_in_cset(r);
if (r->is_young()) {
assert(r->young_index_in_cset() != -1 && (uint)r->young_index_in_cset() < g1h->collection_set()->young_region_length(),
"Young index %d is wrong for region %u of type %s with %u young regions",
r->young_index_in_cset(),
r->hrm_index(),
r->get_type_str(),
g1h->collection_set()->young_region_length());
size_t words_survived = _surviving_young_words[r->young_index_in_cset()];
r->record_surv_words_in_group(words_survived);
}
if (!r->evacuation_failed()) {
assert(r->not_empty(), "Region %u is an empty region in the collection set.", r->hrm_index());
_before_used_bytes += r->used();
g1h->free_region(r,
&_local_free_list,
true, /* skip_remset */
true, /* skip_hot_card_cache */
true /* locked */);
} else {
r->uninstall_surv_rate_group();
r->set_young_index_in_cset(-1);
r->set_evacuation_failed(false);
// When moving a young gen region to old gen, we "allocate" that whole region
// there. This is in addition to any already evacuated objects. Notify the
// policy about that.
// Old gen regions do not cause an additional allocation: both the objects
// still in the region and the ones already moved are accounted for elsewhere.
if (r->is_young()) {
_bytes_allocated_in_old_since_last_gc += HeapRegion::GrainBytes;
}
// The region is now considered to be old.
r->set_old();
// Do some allocation statistics accounting. Regions that failed evacuation
// are always made old, so there is no need to update anything in the young
// gen statistics, but we need to update old gen statistics.
size_t used_words = r->marked_bytes() / HeapWordSize;
_failure_used_words += used_words;
_failure_waste_words += HeapRegion::GrainWords - used_words;
g1h->old_set_add(r);
_after_used_bytes += r->used();
}
return false;
}
void complete_work() {
G1CollectedHeap* g1h = G1CollectedHeap::heap();
_evacuation_info->set_regions_freed(_local_free_list.length());
_evacuation_info->increment_collectionset_used_after(_after_used_bytes);
g1h->prepend_to_freelist(&_local_free_list);
g1h->decrement_summary_bytes(_before_used_bytes);
G1Policy* policy = g1h->g1_policy();
policy->add_bytes_allocated_in_old_since_last_gc(_bytes_allocated_in_old_since_last_gc);
g1h->alloc_buffer_stats(InCSetState::Old)->add_failure_used_and_waste(_failure_used_words, _failure_waste_words);
}
};
G1CollectionSet* _collection_set;
G1SerialFreeCollectionSetClosure _cl;
const size_t* _surviving_young_words;
FreeRegionList _local_free_list;
size_t _rs_lengths;
// Bytes used in successfully evacuated regions before the evacuation.
size_t _before_used_bytes;
// Bytes used in unsucessfully evacuated regions before the evacuation
size_t _after_used_bytes;
size_t _bytes_allocated_in_old_since_last_gc;
volatile jint _serial_work_claim;
size_t _failure_used_words;
size_t _failure_waste_words;
struct WorkItem {
uint region_idx;
bool is_young;
bool evacuation_failed;
double _young_time;
double _non_young_time;
public:
G1FreeCollectionSetClosure(const size_t* surviving_young_words) :
HeapRegionClosure(),
_surviving_young_words(surviving_young_words),
_local_free_list("Local Region List for CSet Freeing"),
_rs_lengths(0),
_before_used_bytes(0),
_after_used_bytes(0),
_bytes_allocated_in_old_since_last_gc(0),
_failure_used_words(0),
_failure_waste_words(0),
_young_time(0.0),
_non_young_time(0.0) {
WorkItem(HeapRegion* r) {
region_idx = r->hrm_index();
is_young = r->is_young();
evacuation_failed = r->evacuation_failed();
}
};
volatile size_t _parallel_work_claim;
size_t _num_work_items;
WorkItem* _work_items;
void do_serial_work() {
// Need to grab the lock to be allowed to modify the old region list.
MutexLockerEx x(OldSets_lock, Mutex::_no_safepoint_check_flag);
_collection_set->iterate(&_cl);
}
virtual bool doHeapRegion(HeapRegion* r) {
double start_time = os::elapsedTime();
bool is_young = r->is_young();
void do_parallel_work_for_region(uint region_idx, bool is_young, bool evacuation_failed) {
G1CollectedHeap* g1h = G1CollectedHeap::heap();
HeapRegion* r = g1h->region_at(region_idx);
assert(!g1h->is_on_master_free_list(r), "sanity");
_rs_lengths += r->rem_set()->occupied_locked();
Atomic::add(r->rem_set()->occupied_locked(), &_rs_lengths);
assert(r->in_collection_set(), "Region %u should be in collection set.", r->hrm_index());
g1h->clear_in_cset(r);
if (is_young) {
int index = r->young_index_in_cset();
assert(index != -1, "Young index in collection set must not be -1 for region %u", r->hrm_index());
assert((uint) index < g1h->collection_set()->young_region_length(), "invariant");
size_t words_survived = _surviving_young_words[index];
r->record_surv_words_in_group(words_survived);
} else {
assert(r->young_index_in_cset() == -1, "Young index for old region %u in collection set must be -1", r->hrm_index());
if (!is_young) {
g1h->_hot_card_cache->reset_card_counts(r);
}
if (!r->evacuation_failed()) {
assert(r->not_empty(), "Region %u is an empty region in the collection set.", r->hrm_index());
_before_used_bytes += r->used();
g1h->free_region(r, &_local_free_list, false /* par */, true /* locked */);
} else {
r->uninstall_surv_rate_group();
r->set_young_index_in_cset(-1);
r->set_evacuation_failed(false);
// When moving a young gen region to old gen, we "allocate" that whole region
// there. This is in addition to any already evacuated objects. Notify the
// policy about that.
// Old gen regions do not cause an additional allocation: both the objects
// still in the region and the ones already moved are accounted for elsewhere.
if (is_young) {
_bytes_allocated_in_old_since_last_gc += HeapRegion::GrainBytes;
}
// The region is now considered to be old.
r->set_old();
// Do some allocation statistics accounting. Regions that failed evacuation
// are always made old, so there is no need to update anything in the young
// gen statistics, but we need to update old gen statistics.
size_t used_words = r->marked_bytes() / HeapWordSize;
_failure_used_words += used_words;
_failure_waste_words += HeapRegion::GrainWords - used_words;
g1h->old_set_add(r);
_after_used_bytes += r->used();
if (!evacuation_failed) {
r->rem_set()->clear_locked();
}
if (is_young) {
_young_time += os::elapsedTime() - start_time;
} else {
_non_young_time += os::elapsedTime() - start_time;
}
return false;
}
FreeRegionList* local_free_list() { return &_local_free_list; }
size_t rs_lengths() const { return _rs_lengths; }
size_t before_used_bytes() const { return _before_used_bytes; }
size_t after_used_bytes() const { return _after_used_bytes; }
class G1PrepareFreeCollectionSetClosure : public HeapRegionClosure {
private:
size_t _cur_idx;
WorkItem* _work_items;
public:
G1PrepareFreeCollectionSetClosure(WorkItem* work_items) : HeapRegionClosure(), _cur_idx(0), _work_items(work_items) { }
size_t bytes_allocated_in_old_since_last_gc() const { return _bytes_allocated_in_old_since_last_gc; }
virtual bool doHeapRegion(HeapRegion* r) {
_work_items[_cur_idx++] = WorkItem(r);
return false;
}
};
size_t failure_used_words() const { return _failure_used_words; }
size_t failure_waste_words() const { return _failure_waste_words; }
void prepare_work() {
G1PrepareFreeCollectionSetClosure cl(_work_items);
_collection_set->iterate(&cl);
}
double young_time() const { return _young_time; }
double non_young_time() const { return _non_young_time; }
void complete_work() {
_cl.complete_work();
G1Policy* policy = G1CollectedHeap::heap()->g1_policy();
policy->record_max_rs_lengths(_rs_lengths);
policy->cset_regions_freed();
}
public:
G1FreeCollectionSetTask(G1CollectionSet* collection_set, EvacuationInfo* evacuation_info, const size_t* surviving_young_words) :
AbstractGangTask("G1 Free Collection Set"),
_cl(evacuation_info, surviving_young_words),
_collection_set(collection_set),
_surviving_young_words(surviving_young_words),
_serial_work_claim(0),
_rs_lengths(0),
_parallel_work_claim(0),
_num_work_items(collection_set->region_length()),
_work_items(NEW_C_HEAP_ARRAY(WorkItem, _num_work_items, mtGC)) {
prepare_work();
}
~G1FreeCollectionSetTask() {
complete_work();
FREE_C_HEAP_ARRAY(WorkItem, _work_items);
}
// Chunk size for work distribution. The chosen value has been determined experimentally
// to be a good tradeoff between overhead and achievable parallelism.
static uint chunk_size() { return 32; }
virtual void work(uint worker_id) {
G1GCPhaseTimes* timer = G1CollectedHeap::heap()->g1_policy()->phase_times();
// Claim serial work.
if (_serial_work_claim == 0) {
jint value = Atomic::add(1, &_serial_work_claim) - 1;
if (value == 0) {
double serial_time = os::elapsedTime();
do_serial_work();
timer->record_serial_free_cset_time_ms((os::elapsedTime() - serial_time) * 1000.0);
}
}
// Start parallel work.
double young_time = 0.0;
bool has_young_time = false;
double non_young_time = 0.0;
bool has_non_young_time = false;
while (true) {
size_t end = Atomic::add(chunk_size(), &_parallel_work_claim);
size_t cur = end - chunk_size();
if (cur >= _num_work_items) {
break;
}
double start_time = os::elapsedTime();
end = MIN2(end, _num_work_items);
for (; cur < end; cur++) {
bool is_young = _work_items[cur].is_young;
do_parallel_work_for_region(_work_items[cur].region_idx, is_young, _work_items[cur].evacuation_failed);
double end_time = os::elapsedTime();
double time_taken = end_time - start_time;
if (is_young) {
young_time += time_taken;
has_young_time = true;
} else {
non_young_time += time_taken;
has_non_young_time = true;
}
start_time = end_time;
}
}
if (has_young_time) {
timer->record_time_secs(G1GCPhaseTimes::YoungFreeCSet, worker_id, young_time);
}
if (has_non_young_time) {
timer->record_time_secs(G1GCPhaseTimes::NonYoungFreeCSet, worker_id, young_time);
}
}
};
void G1CollectedHeap::free_collection_set(G1CollectionSet* collection_set, EvacuationInfo& evacuation_info, const size_t* surviving_young_words) {
_eden.clear();
G1FreeCollectionSetClosure cl(surviving_young_words);
collection_set_iterate(&cl);
double free_cset_start_time = os::elapsedTime();
evacuation_info.set_regions_freed(cl.local_free_list()->length());
evacuation_info.increment_collectionset_used_after(cl.after_used_bytes());
{
uint const num_chunks = MAX2(_collection_set.region_length() / G1FreeCollectionSetTask::chunk_size(), 1U);
uint const num_workers = MIN2(workers()->active_workers(), num_chunks);
G1Policy* policy = g1_policy();
G1FreeCollectionSetTask cl(collection_set, &evacuation_info, surviving_young_words);
policy->record_max_rs_lengths(cl.rs_lengths());
policy->cset_regions_freed();
prepend_to_freelist(cl.local_free_list());
decrement_summary_bytes(cl.before_used_bytes());
policy->add_bytes_allocated_in_old_since_last_gc(cl.bytes_allocated_in_old_since_last_gc());
_old_evac_stats.add_failure_used_and_waste(cl.failure_used_words(), cl.failure_waste_words());
policy->phase_times()->record_young_free_cset_time_ms(cl.young_time() * 1000.0);
policy->phase_times()->record_non_young_free_cset_time_ms(cl.non_young_time() * 1000.0);
log_debug(gc, ergo)("Running %s using %u workers for collection set length %u",
cl.name(),
num_workers,
_collection_set.region_length());
workers()->run_task(&cl, num_workers);
}
g1_policy()->phase_times()->record_total_free_cset_time_ms((os::elapsedTime() - free_cset_start_time) * 1000.0);
collection_set->clear();
}
@ -4825,7 +4969,7 @@ class G1FreeHumongousRegionClosure : public HeapRegionClosure {
_freed_bytes += r->used();
r->set_containing_set(NULL);
_humongous_regions_removed++;
g1h->free_humongous_region(r, _free_region_list, false);
g1h->free_humongous_region(r, _free_region_list, false /* skip_remset */ );
r = next;
} while (r != NULL);

13
hotspot/src/share/vm/gc/g1/g1CollectedHeap.hpp
View File

@ -118,6 +118,7 @@ class G1RegionMappingChangedListener : public G1MappingChangedListener {
};
class G1CollectedHeap : public CollectedHeap {
friend class G1FreeCollectionSetTask;
friend class VM_CollectForMetadataAllocation;
friend class VM_G1CollectForAllocation;
friend class VM_G1CollectFull;
@ -642,13 +643,15 @@ public:
// adding it to the free list that's passed as a parameter (this is
// usually a local list which will be appended to the master free
// list later). The used bytes of freed regions are accumulated in
// pre_used. If par is true, the region's RSet will not be freed
// up. The assumption is that this will be done later.
// pre_used. If skip_remset is true, the region's RSet will not be freed
// up. If skip_hot_card_cache is true, the region's hot card cache will not
// be freed up. The assumption is that this will be done later.
// The locked parameter indicates if the caller has already taken
// care of proper synchronization. This may allow some optimizations.
void free_region(HeapRegion* hr,
FreeRegionList* free_list,
bool par,
bool skip_remset,
bool skip_hot_card_cache = false,
bool locked = false);
// It dirties the cards that cover the block so that the post
@ -662,11 +665,11 @@ public:
// will be added to the free list that's passed as a parameter (this
// is usually a local list which will be appended to the master free
// list later). The used bytes of freed regions are accumulated in
// pre_used. If par is true, the region's RSet will not be freed
// pre_used. If skip_remset is true, the region's RSet will not be freed
// up. The assumption is that this will be done later.
void free_humongous_region(HeapRegion* hr,
FreeRegionList* free_list,
bool par);
bool skip_remset);
// Facility for allocating in 'archive' regions in high heap memory and
// recording the allocated ranges. These should all be called from the

4
hotspot/src/share/vm/gc/g1/g1ConcurrentMark.cpp
View File

@ -1159,10 +1159,10 @@ public:
hr->set_containing_set(NULL);
if (hr->is_humongous()) {
_humongous_regions_removed++;
_g1->free_humongous_region(hr, _local_cleanup_list, true);
_g1->free_humongous_region(hr, _local_cleanup_list, true /* skip_remset */);
} else {
_old_regions_removed++;
_g1->free_region(hr, _local_cleanup_list, true);
_g1->free_region(hr, _local_cleanup_list, true /* skip_remset */);
}
} else {
hr->rem_set()->do_cleanup_work(_hrrs_cleanup_task);

7
hotspot/src/share/vm/gc/g1/g1DefaultPolicy.cpp
View File

@ -501,13 +501,12 @@ double G1DefaultPolicy::average_time_ms(G1GCPhaseTimes::GCParPhases phase) const
double G1DefaultPolicy::young_other_time_ms() const {
return phase_times()->young_cset_choice_time_ms() +
phase_times()->young_free_cset_time_ms();
phase_times()->average_time_ms(G1GCPhaseTimes::YoungFreeCSet);
}
double G1DefaultPolicy::non_young_other_time_ms() const {
return phase_times()->non_young_cset_choice_time_ms() +
phase_times()->non_young_free_cset_time_ms();
phase_times()->average_time_ms(G1GCPhaseTimes::NonYoungFreeCSet);
}
double G1DefaultPolicy::other_time_ms(double pause_time_ms) const {
@ -515,7 +514,7 @@ double G1DefaultPolicy::other_time_ms(double pause_time_ms) const {
}
double G1DefaultPolicy::constant_other_time_ms(double pause_time_ms) const {
return other_time_ms(pause_time_ms) - young_other_time_ms() - non_young_other_time_ms();
return other_time_ms(pause_time_ms) - phase_times()->total_free_cset_time_ms();
}
CollectionSetChooser* G1DefaultPolicy::cset_chooser() const {

12
hotspot/src/share/vm/gc/g1/g1GCPhaseTimes.cpp
View File

@ -91,6 +91,9 @@ G1GCPhaseTimes::G1GCPhaseTimes(uint max_gc_threads) :
_redirtied_cards = new WorkerDataArray<size_t>(max_gc_threads, "Redirtied Cards:");
_gc_par_phases[RedirtyCards]->link_thread_work_items(_redirtied_cards);
_gc_par_phases[YoungFreeCSet] = new WorkerDataArray<double>(max_gc_threads, "Young Free Collection Set (ms):");
_gc_par_phases[NonYoungFreeCSet] = new WorkerDataArray<double>(max_gc_threads, "Non-Young Free Collection Set (ms):");
_gc_par_phases[PreserveCMReferents] = new WorkerDataArray<double>(max_gc_threads, "Parallel Preserve CM Refs (ms):");
}
@ -278,10 +281,11 @@ void G1GCPhaseTimes::print() {
info_line_and_account("Clear Card Table", _cur_clear_ct_time_ms);
info_line_and_account("Expand Heap After Collection", _cur_expand_heap_time_ms);
double free_cset_time = _recorded_young_free_cset_time_ms + _recorded_non_young_free_cset_time_ms;
info_line_and_account("Free Collection Set", free_cset_time);
debug_line("Young Free Collection Set", _recorded_young_free_cset_time_ms);
debug_line("Non-Young Free Collection Set", _recorded_non_young_free_cset_time_ms);
info_line_and_account("Free Collection Set", _recorded_total_free_cset_time_ms);
debug_line("Free Collection Set Serial", _recorded_serial_free_cset_time_ms);
debug_phase(_gc_par_phases[YoungFreeCSet]);
debug_phase(_gc_par_phases[NonYoungFreeCSet]);
info_line_and_account("Merge Per-Thread State", _recorded_merge_pss_time_ms);
info_line("Other", _gc_pause_time_ms - accounted_time_ms);

23
hotspot/src/share/vm/gc/g1/g1GCPhaseTimes.hpp
View File

@ -67,6 +67,8 @@ class G1GCPhaseTimes : public CHeapObj<mtGC> {
StringDedupTableFixup,
RedirtyCards,
PreserveCMReferents,
YoungFreeCSet,
NonYoungFreeCSet,
GCParPhasesSentinel
};
@ -110,8 +112,9 @@ class G1GCPhaseTimes : public CHeapObj<mtGC> {
double _recorded_merge_pss_time_ms;
double _recorded_young_free_cset_time_ms;
double _recorded_non_young_free_cset_time_ms;
double _recorded_total_free_cset_time_ms;
double _recorded_serial_free_cset_time_ms;
double _cur_fast_reclaim_humongous_time_ms;
double _cur_fast_reclaim_humongous_register_time_ms;
@ -199,12 +202,12 @@ class G1GCPhaseTimes : public CHeapObj<mtGC> {
_root_region_scan_wait_time_ms = time_ms;
}
void record_young_free_cset_time_ms(double time_ms) {
_recorded_young_free_cset_time_ms = time_ms;
void record_total_free_cset_time_ms(double time_ms) {
_recorded_total_free_cset_time_ms = time_ms;
}
void record_non_young_free_cset_time_ms(double time_ms) {
_recorded_non_young_free_cset_time_ms = time_ms;
void record_serial_free_cset_time_ms(double time_ms) {
_recorded_serial_free_cset_time_ms = time_ms;
}
void record_fast_reclaim_humongous_stats(double time_ms, size_t total, size_t candidates) {
@ -278,18 +281,14 @@ class G1GCPhaseTimes : public CHeapObj<mtGC> {
return _recorded_young_cset_choice_time_ms;
}
double young_free_cset_time_ms() {
return _recorded_young_free_cset_time_ms;
double total_free_cset_time_ms() {
return _recorded_total_free_cset_time_ms;
}
double non_young_cset_choice_time_ms() {
return _recorded_non_young_cset_choice_time_ms;
}
double non_young_free_cset_time_ms() {
return _recorded_non_young_free_cset_time_ms;
}
double fast_reclaim_humongous_time_ms() {
return _cur_fast_reclaim_humongous_time_ms;
}

2
hotspot/src/share/vm/gc/g1/g1MarkSweep.cpp
View File

@ -340,7 +340,7 @@ void G1PrepareCompactClosure::free_humongous_region(HeapRegion* hr) {
hr->set_containing_set(NULL);
_humongous_regions_removed++;
_g1h->free_humongous_region(hr, &dummy_free_list, false /* par */);
_g1h->free_humongous_region(hr, &dummy_free_list, false /* skip_remset */);
prepare_for_compaction(hr, end);
dummy_free_list.remove_all();
}

11
hotspot/src/share/vm/gc/g1/heapRegion.cpp
View File

@ -167,7 +167,7 @@ void HeapRegion::reset_after_compaction() {
init_top_at_mark_start();
}
void HeapRegion::hr_clear(bool par, bool clear_space, bool locked) {
void HeapRegion::hr_clear(bool keep_remset, bool clear_space, bool locked) {
assert(_humongous_start_region == NULL,
"we should have already filtered out humongous regions");
assert(!in_collection_set(),
@ -179,15 +179,14 @@ void HeapRegion::hr_clear(bool par, bool clear_space, bool locked) {
set_free();
reset_pre_dummy_top();
if (!par) {
// If this is parallel, this will be done later.
HeapRegionRemSet* hrrs = rem_set();
if (!keep_remset) {
if (locked) {
hrrs->clear_locked();
rem_set()->clear_locked();
} else {
hrrs->clear();
rem_set()->clear();
}
}
zero_marked_bytes();
init_top_at_mark_start();

7
hotspot/src/share/vm/gc/g1/heapRegion.hpp
View File

@ -512,8 +512,11 @@ class HeapRegion: public G1ContiguousSpace {
#endif // ASSERT
// Reset HR stuff to default values.
void hr_clear(bool par, bool clear_space, bool locked = false);
// Reset the HeapRegion to default values.
// If skip_remset is true, do not clear the remembered set.
void hr_clear(bool skip_remset, bool clear_space, bool locked = false);
// Clear the parts skipped by skip_remset in hr_clear() in the HeapRegion during
// a concurrent phase.
void par_clear();
// Get the start of the unmarked area in this region.

2
hotspot/test/gc/g1/TestGCLogMessages.java
View File

@ -95,6 +95,8 @@ public class TestGCLogMessages {
new LogMessageWithLevel("String Dedup Fixup", Level.INFO),
new LogMessageWithLevel("Expand Heap After Collection", Level.INFO),
// Free CSet
new LogMessageWithLevel("Free Collection Set", Level.INFO),
new LogMessageWithLevel("Free Collection Set Serial", Level.DEBUG),
new LogMessageWithLevel("Young Free Collection Set", Level.DEBUG),
new LogMessageWithLevel("Non-Young Free Collection Set", Level.DEBUG),
// Humongous Eager Reclaim