diff --git a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp index a2979ee58a3fe63dc62997b293b318f95f6758c6..d0b0a79f586e76c4a529836f50e2b7a5103e423b 100644 --- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp +++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp @@ -3590,15 +3590,11 @@ size_t G1CollectedHeap::pending_card_num() { DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); size_t buffer_size = dcqs.buffer_size(); size_t buffer_num = dcqs.completed_buffers_num(); - return buffer_size * buffer_num + extra_cards; -} -size_t G1CollectedHeap::max_pending_card_num() { - DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); - size_t buffer_size = dcqs.buffer_size(); - size_t buffer_num = dcqs.completed_buffers_num(); - int thread_num = Threads::number_of_threads(); - return (buffer_num + thread_num) * buffer_size; + // PtrQueueSet::buffer_size() and PtrQueue:size() return sizes + // in bytes - not the number of 'entries'. We need to convert + // into a number of cards. + return (buffer_size * buffer_num + extra_cards) / oopSize; } size_t G1CollectedHeap::cards_scanned() { diff --git a/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp b/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp index 2c9a3d03198abc553473b015137f61777a4f8f4f..901248d776edb176c8486a042caf6bc4619924e8 100644 --- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp +++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp @@ -1706,7 +1706,6 @@ public: void stop_conc_gc_threads(); size_t pending_card_num(); - size_t max_pending_card_num(); size_t cards_scanned(); protected: diff --git a/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp b/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp index 4fd1c20ec9172abe29766aaacc6253948b1d22db..6e8bf2c3660576f55cb744da272ba139a113a275 100644 --- a/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp +++ b/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp @@ -90,7 +90,6 @@ G1CollectorPolicy::G1CollectorPolicy() : _alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)), _prev_collection_pause_end_ms(0.0), - _pending_card_diff_seq(new TruncatedSeq(TruncatedSeqLength)), _rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)), _cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)), _young_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)), @@ -197,7 +196,6 @@ G1CollectorPolicy::G1CollectorPolicy() : int index = MIN2(_parallel_gc_threads - 1, 7); - _pending_card_diff_seq->add(0.0); _rs_length_diff_seq->add(rs_length_diff_defaults[index]); _cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]); _young_cards_per_entry_ratio_seq->add( @@ -657,7 +655,7 @@ double G1CollectorPolicy::predict_survivor_regions_evac_time() { for (HeapRegion * r = _recorded_survivor_head; r != NULL && r != _recorded_survivor_tail->get_next_young_region(); r = r->get_next_young_region()) { - survivor_regions_evac_time += predict_region_elapsed_time_ms(r, true); + survivor_regions_evac_time += predict_region_elapsed_time_ms(r, gcs_are_young()); } return survivor_regions_evac_time; } @@ -801,9 +799,8 @@ void G1CollectorPolicy::record_collection_pause_start(double start_time_sec, _cur_collection_pause_used_at_start_bytes = start_used; _cur_collection_pause_used_regions_at_start = _g1->used_regions(); _pending_cards = _g1->pending_card_num(); - _max_pending_cards = _g1->max_pending_card_num(); - _bytes_in_collection_set_before_gc = 0; + _collection_set_bytes_used_before = 0; _bytes_copied_during_gc = 0; YoungList* young_list = _g1->young_list(); @@ -1036,12 +1033,6 @@ void G1CollectorPolicy::record_collection_pause_end(double pause_time_ms) { // do that for any other surv rate groupsx if (update_stats) { - size_t diff = 0; - if (_max_pending_cards >= _pending_cards) { - diff = _max_pending_cards - _pending_cards; - } - _pending_card_diff_seq->add((double) diff); - double cost_per_card_ms = 0.0; if (_pending_cards > 0) { cost_per_card_ms = phase_times()->_update_rs_time / (double) _pending_cards; @@ -1126,9 +1117,9 @@ void G1CollectorPolicy::record_collection_pause_end(double pause_time_ms) { _constant_other_time_ms_seq->add(constant_other_time_ms); double survival_ratio = 0.0; - if (_bytes_in_collection_set_before_gc > 0) { + if (_collection_set_bytes_used_before > 0) { survival_ratio = (double) _bytes_copied_during_gc / - (double) _bytes_in_collection_set_before_gc; + (double) _collection_set_bytes_used_before; } _pending_cards_seq->add((double) _pending_cards); @@ -1228,6 +1219,15 @@ void G1CollectorPolicy::adjust_concurrent_refinement(double update_rs_time, dcqs.notify_if_necessary(); } +double +G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards, + size_t scanned_cards) { + return + predict_rs_update_time_ms(pending_cards) + + predict_rs_scan_time_ms(scanned_cards) + + predict_constant_other_time_ms(); +} + double G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards) { size_t rs_length = predict_rs_length_diff(); @@ -1240,21 +1240,28 @@ G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards) { return predict_base_elapsed_time_ms(pending_cards, card_num); } -double -G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards, - size_t scanned_cards) { - return - predict_rs_update_time_ms(pending_cards) + - predict_rs_scan_time_ms(scanned_cards) + - predict_constant_other_time_ms(); +size_t G1CollectorPolicy::predict_bytes_to_copy(HeapRegion* hr) { + size_t bytes_to_copy; + if (hr->is_marked()) + bytes_to_copy = hr->max_live_bytes(); + else { + assert(hr->is_young() && hr->age_in_surv_rate_group() != -1, "invariant"); + int age = hr->age_in_surv_rate_group(); + double yg_surv_rate = predict_yg_surv_rate(age, hr->surv_rate_group()); + bytes_to_copy = (size_t) ((double) hr->used() * yg_surv_rate); + } + return bytes_to_copy; } double G1CollectorPolicy::predict_region_elapsed_time_ms(HeapRegion* hr, - bool young) { + bool for_young_gc) { size_t rs_length = hr->rem_set()->occupied(); size_t card_num; - if (gcs_are_young()) { + + // Predicting the number of cards is based on which type of GC + // we're predicting for. + if (for_young_gc) { card_num = predict_young_card_num(rs_length); } else { card_num = predict_non_young_card_num(rs_length); @@ -1265,25 +1272,14 @@ G1CollectorPolicy::predict_region_elapsed_time_ms(HeapRegion* hr, predict_rs_scan_time_ms(card_num) + predict_object_copy_time_ms(bytes_to_copy); - if (young) + // The prediction of the "other" time for this region is based + // upon the region type and NOT the GC type. + if (hr->is_young()) { region_elapsed_time_ms += predict_young_other_time_ms(1); - else + } else { region_elapsed_time_ms += predict_non_young_other_time_ms(1); - - return region_elapsed_time_ms; -} - -size_t G1CollectorPolicy::predict_bytes_to_copy(HeapRegion* hr) { - size_t bytes_to_copy; - if (hr->is_marked()) - bytes_to_copy = hr->max_live_bytes(); - else { - assert(hr->is_young() && hr->age_in_surv_rate_group() != -1, "invariant"); - int age = hr->age_in_surv_rate_group(); - double yg_surv_rate = predict_yg_surv_rate(age, hr->surv_rate_group()); - bytes_to_copy = (size_t) ((double) hr->used() * yg_surv_rate); } - return bytes_to_copy; + return region_elapsed_time_ms; } void @@ -1342,22 +1338,6 @@ size_t G1CollectorPolicy::expansion_amount() { } } -class CountCSClosure: public HeapRegionClosure { - G1CollectorPolicy* _g1_policy; -public: - CountCSClosure(G1CollectorPolicy* g1_policy) : - _g1_policy(g1_policy) {} - bool doHeapRegion(HeapRegion* r) { - _g1_policy->_bytes_in_collection_set_before_gc += r->used(); - return false; - } -}; - -void G1CollectorPolicy::count_CS_bytes_used() { - CountCSClosure cs_closure(this); - _g1->collection_set_iterate(&cs_closure); -} - void G1CollectorPolicy::print_tracing_info() const { _trace_gen0_time_data.print(); _trace_gen1_time_data.print(); @@ -1696,7 +1676,7 @@ void G1CollectorPolicy::add_to_incremental_cset_info(HeapRegion* hr, size_t rs_l // retiring the current allocation region) or a concurrent // refine thread (RSet sampling). - double region_elapsed_time_ms = predict_region_elapsed_time_ms(hr, true); + double region_elapsed_time_ms = predict_region_elapsed_time_ms(hr, gcs_are_young()); size_t used_bytes = hr->used(); _inc_cset_recorded_rs_lengths += rs_length; _inc_cset_predicted_elapsed_time_ms += region_elapsed_time_ms; @@ -1731,7 +1711,7 @@ void G1CollectorPolicy::update_incremental_cset_info(HeapRegion* hr, _inc_cset_recorded_rs_lengths_diffs += rs_lengths_diff; double old_elapsed_time_ms = hr->predicted_elapsed_time_ms(); - double new_region_elapsed_time_ms = predict_region_elapsed_time_ms(hr, true); + double new_region_elapsed_time_ms = predict_region_elapsed_time_ms(hr, gcs_are_young()); double elapsed_ms_diff = new_region_elapsed_time_ms - old_elapsed_time_ms; _inc_cset_predicted_elapsed_time_ms_diffs += elapsed_ms_diff; @@ -1854,8 +1834,7 @@ bool G1CollectorPolicy::next_gc_should_be_mixed(const char* true_action_str, } void G1CollectorPolicy::finalize_cset(double target_pause_time_ms) { - // Set this here - in case we're not doing young collections. - double non_young_start_time_sec = os::elapsedTime(); + double young_start_time_sec = os::elapsedTime(); YoungList* young_list = _g1->young_list(); finalize_incremental_cset_building(); @@ -1869,17 +1848,14 @@ void G1CollectorPolicy::finalize_cset(double target_pause_time_ms) { double predicted_pause_time_ms = base_time_ms; double time_remaining_ms = target_pause_time_ms - base_time_ms; - ergo_verbose3(ErgoCSetConstruction | ErgoHigh, + ergo_verbose4(ErgoCSetConstruction | ErgoHigh, "start choosing CSet", + ergo_format_size("_pending_cards") ergo_format_ms("predicted base time") ergo_format_ms("remaining time") ergo_format_ms("target pause time"), - base_time_ms, time_remaining_ms, target_pause_time_ms); - - HeapRegion* hr; - double young_start_time_sec = os::elapsedTime(); + _pending_cards, base_time_ms, time_remaining_ms, target_pause_time_ms); - _collection_set_bytes_used_before = 0; _last_gc_was_young = gcs_are_young() ? true : false; if (_last_gc_was_young) { @@ -1895,7 +1871,8 @@ void G1CollectorPolicy::finalize_cset(double target_pause_time_ms) { uint survivor_region_length = young_list->survivor_length(); uint eden_region_length = young_list->length() - survivor_region_length; init_cset_region_lengths(eden_region_length, survivor_region_length); - hr = young_list->first_survivor_region(); + + HeapRegion* hr = young_list->first_survivor_region(); while (hr != NULL) { assert(hr->is_survivor(), "badly formed young list"); hr->set_young(); @@ -1926,8 +1903,8 @@ void G1CollectorPolicy::finalize_cset(double target_pause_time_ms) { phase_times()->_recorded_young_cset_choice_time_ms = (young_end_time_sec - young_start_time_sec) * 1000.0; - // We are doing young collections so reset this. - non_young_start_time_sec = young_end_time_sec; + // Set the start of the non-young choice time. + double non_young_start_time_sec = young_end_time_sec; if (!gcs_are_young()) { CollectionSetChooser* cset_chooser = _collectionSetChooser; @@ -1937,6 +1914,7 @@ void G1CollectorPolicy::finalize_cset(double target_pause_time_ms) { uint expensive_region_num = 0; bool check_time_remaining = adaptive_young_list_length(); + HeapRegion* hr = cset_chooser->peek(); while (hr != NULL) { if (old_cset_region_length() >= max_old_cset_length) { @@ -1950,7 +1928,7 @@ void G1CollectorPolicy::finalize_cset(double target_pause_time_ms) { break; } - double predicted_time_ms = predict_region_elapsed_time_ms(hr, false); + double predicted_time_ms = predict_region_elapsed_time_ms(hr, gcs_are_young()); if (check_time_remaining) { if (predicted_time_ms > time_remaining_ms) { // Too expensive for the current CSet. @@ -2025,8 +2003,6 @@ void G1CollectorPolicy::finalize_cset(double target_pause_time_ms) { stop_incremental_cset_building(); - count_CS_bytes_used(); - ergo_verbose5(ErgoCSetConstruction, "finish choosing CSet", ergo_format_region("eden") diff --git a/src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp b/src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp index 3fa36acc3a39021e92b20580a7e9a61ada6fbc23..da664b3835ea26be3de5fe1ae57c913843e88a9c 100644 --- a/src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp +++ b/src/share/vm/gc_implementation/g1/g1CollectorPolicy.hpp @@ -228,7 +228,6 @@ private: TruncatedSeq* _alloc_rate_ms_seq; double _prev_collection_pause_end_ms; - TruncatedSeq* _pending_card_diff_seq; TruncatedSeq* _rs_length_diff_seq; TruncatedSeq* _cost_per_card_ms_seq; TruncatedSeq* _young_cards_per_entry_ratio_seq; @@ -295,7 +294,6 @@ private: double _pause_time_target_ms; size_t _pending_cards; - size_t _max_pending_cards; public: // Accessors @@ -325,28 +323,6 @@ public: _max_rs_lengths = rs_lengths; } - size_t predict_pending_card_diff() { - double prediction = get_new_neg_prediction(_pending_card_diff_seq); - if (prediction < 0.00001) { - return 0; - } else { - return (size_t) prediction; - } - } - - size_t predict_pending_cards() { - size_t max_pending_card_num = _g1->max_pending_card_num(); - size_t diff = predict_pending_card_diff(); - size_t prediction; - if (diff > max_pending_card_num) { - prediction = max_pending_card_num; - } else { - prediction = max_pending_card_num - diff; - } - - return prediction; - } - size_t predict_rs_length_diff() { return (size_t) get_new_prediction(_rs_length_diff_seq); } @@ -439,7 +415,7 @@ public: double predict_base_elapsed_time_ms(size_t pending_cards, size_t scanned_cards); size_t predict_bytes_to_copy(HeapRegion* hr); - double predict_region_elapsed_time_ms(HeapRegion* hr, bool young); + double predict_region_elapsed_time_ms(HeapRegion* hr, bool for_young_gc); void set_recorded_rs_lengths(size_t rs_lengths); @@ -495,12 +471,6 @@ public: } private: - size_t _bytes_in_collection_set_before_gc; - size_t _bytes_copied_during_gc; - - // Used to count used bytes in CS. - friend class CountCSClosure; - // Statistics kept per GC stoppage, pause or full. TruncatedSeq* _recent_prev_end_times_for_all_gcs_sec; @@ -514,9 +484,13 @@ private: // The number of bytes in the collection set before the pause. Set from // the incrementally built collection set at the start of an evacuation - // pause. + // pause, and incremented in finalize_cset() when adding old regions + // (if any) to the collection set. size_t _collection_set_bytes_used_before; + // The number of bytes copied during the GC. + size_t _bytes_copied_during_gc; + // The associated information that is maintained while the incremental // collection set is being built with young regions. Used to populate // the recorded info for the evacuation pause. @@ -646,9 +620,6 @@ private: bool predict_will_fit(uint young_length, double base_time_ms, uint base_free_regions, double target_pause_time_ms); - // Count the number of bytes used in the CS. - void count_CS_bytes_used(); - public: G1CollectorPolicy(); @@ -666,10 +637,6 @@ public: // higher, recalculate the young list target length prediction. void revise_young_list_target_length_if_necessary(); - size_t bytes_in_collection_set() { - return _bytes_in_collection_set_before_gc; - } - // This should be called after the heap is resized. void record_new_heap_size(uint new_number_of_regions); diff --git a/src/share/vm/gc_implementation/g1/g1ErgoVerbose.hpp b/src/share/vm/gc_implementation/g1/g1ErgoVerbose.hpp index 20d34ddb7ff26149953a300637c4f10a5e452dab..eff119625be19d89b2a2fcc603d79d6389a02b7f 100644 --- a/src/share/vm/gc_implementation/g1/g1ErgoVerbose.hpp +++ b/src/share/vm/gc_implementation/g1/g1ErgoVerbose.hpp @@ -125,6 +125,7 @@ public: #define ergo_format_double(_name_) ", " _name_ ": %1.2f" #define ergo_format_perc(_name_) ", " _name_ ": %1.2f %%" #define ergo_format_ms(_name_) ", " _name_ ": %1.2f ms" +#define ergo_format_size(_name_) ", " _name_ ": "SIZE_FORMAT // Double parameter format strings #define ergo_format_byte_perc(_name_) \ diff --git a/src/share/vm/gc_implementation/g1/heapRegion.cpp b/src/share/vm/gc_implementation/g1/heapRegion.cpp index 3d8dead5b6bce65b38176d9f0a9bf6d7852f40de..a6046f10a8f56dbed3ac673b0c00e50a7dd9dfbd 100644 --- a/src/share/vm/gc_implementation/g1/heapRegion.cpp +++ b/src/share/vm/gc_implementation/g1/heapRegion.cpp @@ -384,10 +384,17 @@ void HeapRegion::par_clear() { } void HeapRegion::calc_gc_efficiency() { + // GC efficiency is the ratio of how much space would be + // reclaimed over how long we predict it would take to reclaim it. G1CollectedHeap* g1h = G1CollectedHeap::heap(); G1CollectorPolicy* g1p = g1h->g1_policy(); - _gc_efficiency = (double) reclaimable_bytes() / - g1p->predict_region_elapsed_time_ms(this, false); + + // Retrieve a prediction of the elapsed time for this region for + // a mixed gc because the region will only be evacuated during a + // mixed gc. + double region_elapsed_time_ms = + g1p->predict_region_elapsed_time_ms(this, false /* for_young_gc */); + _gc_efficiency = (double) reclaimable_bytes() / region_elapsed_time_ms; } void HeapRegion::set_startsHumongous(HeapWord* new_top, HeapWord* new_end) {