< prev index next >
src/share/vm/gc/g1/g1Analytics.cpp
Print this page
rev 10473 : [mq]: rename-to-analytics
*** 1,7 ****
/*
! * Copyright (c) 2001, 2016, 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.
--- 1,7 ----
/*
! * Copyright (c) 2016, 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.
*** 21,47 ****
* questions.
*
*/
#include "precompiled.hpp"
! #include "gc/g1/concurrentG1Refine.hpp"
! #include "gc/g1/concurrentMarkThread.inline.hpp"
! #include "gc/g1/g1CollectedHeap.inline.hpp"
! #include "gc/g1/g1CollectionSet.hpp"
! #include "gc/g1/g1CollectorPolicy.hpp"
! #include "gc/g1/g1ConcurrentMark.hpp"
! #include "gc/g1/g1IHOPControl.hpp"
! #include "gc/g1/g1GCPhaseTimes.hpp"
! #include "gc/g1/g1YoungGenSizer.hpp"
! #include "gc/g1/heapRegion.inline.hpp"
! #include "gc/g1/heapRegionRemSet.hpp"
! #include "gc/shared/gcPolicyCounters.hpp"
! #include "runtime/arguments.hpp"
! #include "runtime/java.hpp"
! #include "runtime/mutexLocker.hpp"
#include "utilities/debug.hpp"
! #include "utilities/pair.hpp"
// Different defaults for different number of GC threads
// They were chosen by running GCOld and SPECjbb on debris with different
// numbers of GC threads and choosing them based on the results
--- 21,35 ----
* questions.
*
*/
#include "precompiled.hpp"
! #include "gc/g1/g1Analytics.hpp"
! #include "gc/g1/g1Predictions.hpp"
! #include "runtime/os.hpp"
#include "utilities/debug.hpp"
! #include "utilities/numberSeq.hpp"
// Different defaults for different number of GC threads
// They were chosen by running GCOld and SPECjbb on debris with different
// numbers of GC threads and choosing them based on the results
*** 79,96 ****
static double non_young_other_cost_per_region_ms_defaults[] = {
1.0, 0.7, 0.7, 0.5, 0.5, 0.42, 0.42, 0.30
};
! G1CollectorPolicy::G1CollectorPolicy() :
! _predictor(G1ConfidencePercent / 100.0),
!
_recent_gc_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
-
_concurrent_mark_remark_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
_concurrent_mark_cleanup_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
-
_alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_prev_collection_pause_end_ms(0.0),
_rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_scan_hcc_seq(new TruncatedSeq(TruncatedSeqLength)),
--- 67,81 ----
static double non_young_other_cost_per_region_ms_defaults[] = {
1.0, 0.7, 0.7, 0.5, 0.5, 0.42, 0.42, 0.30
};
! G1Analytics::G1Analytics(const G1Predictions* predictor) :
! _predictor(predictor),
_recent_gc_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
_concurrent_mark_remark_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
_concurrent_mark_cleanup_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
_alloc_rate_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_prev_collection_pause_end_ms(0.0),
_rs_length_diff_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_per_card_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_scan_hcc_seq(new TruncatedSeq(TruncatedSeqLength)),
*** 100,883 ****
_mixed_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_per_byte_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_per_byte_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
_constant_other_time_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
! _non_young_other_cost_per_region_ms_seq(
! new TruncatedSeq(TruncatedSeqLength)),
!
_pending_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
_rs_lengths_seq(new TruncatedSeq(TruncatedSeqLength)),
! _pause_time_target_ms((double) MaxGCPauseMillis),
!
! _recent_prev_end_times_for_all_gcs_sec(
! new TruncatedSeq(NumPrevPausesForHeuristics)),
!
! _recent_avg_pause_time_ratio(0.0),
! _rs_lengths_prediction(0),
! _max_survivor_regions(0),
!
! // add here any more surv rate groups
! _survivors_age_table(true),
!
! _gc_overhead_perc(0.0),
!
! _bytes_allocated_in_old_since_last_gc(0),
! _ihop_control(NULL),
! _initial_mark_to_mixed() {
!
! // SurvRateGroups below must be initialized after the predictor because they
! // indirectly use it through this object passed to their constructor.
! _short_lived_surv_rate_group =
! new SurvRateGroup(&_predictor, "Short Lived", G1YoungSurvRateNumRegionsSummary);
! _survivor_surv_rate_group =
! new SurvRateGroup(&_predictor, "Survivor", G1YoungSurvRateNumRegionsSummary);
!
! // Set up the region size and associated fields. Given that the
! // policy is created before the heap, we have to set this up here,
! // so it's done as soon as possible.
!
! // It would have been natural to pass initial_heap_byte_size() and
! // max_heap_byte_size() to setup_heap_region_size() but those have
! // not been set up at this point since they should be aligned with
! // the region size. So, there is a circular dependency here. We base
! // the region size on the heap size, but the heap size should be
! // aligned with the region size. To get around this we use the
! // unaligned values for the heap.
! HeapRegion::setup_heap_region_size(InitialHeapSize, MaxHeapSize);
! HeapRegionRemSet::setup_remset_size();
!
_recent_prev_end_times_for_all_gcs_sec->add(os::elapsedTime());
_prev_collection_pause_end_ms = os::elapsedTime() * 1000.0;
- clear_ratio_check_data();
-
- _phase_times = new G1GCPhaseTimes(ParallelGCThreads);
int index = MIN2(ParallelGCThreads - 1, 7u);
_rs_length_diff_seq->add(rs_length_diff_defaults[index]);
_cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]);
_cost_scan_hcc_seq->add(0.0);
! _young_cards_per_entry_ratio_seq->add(
! young_cards_per_entry_ratio_defaults[index]);
_cost_per_entry_ms_seq->add(cost_per_entry_ms_defaults[index]);
_cost_per_byte_ms_seq->add(cost_per_byte_ms_defaults[index]);
_constant_other_time_ms_seq->add(constant_other_time_ms_defaults[index]);
! _young_other_cost_per_region_ms_seq->add(
! young_other_cost_per_region_ms_defaults[index]);
! _non_young_other_cost_per_region_ms_seq->add(
! non_young_other_cost_per_region_ms_defaults[index]);
!
! // Below, we might need to calculate the pause time target based on
! // the pause interval. When we do so we are going to give G1 maximum
! // flexibility and allow it to do pauses when it needs to. So, we'll
! // arrange that the pause interval to be pause time target + 1 to
! // ensure that a) the pause time target is maximized with respect to
! // the pause interval and b) we maintain the invariant that pause
! // time target < pause interval. If the user does not want this
! // maximum flexibility, they will have to set the pause interval
! // explicitly.
!
! // First make sure that, if either parameter is set, its value is
! // reasonable.
! if (!FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
! if (MaxGCPauseMillis < 1) {
! vm_exit_during_initialization("MaxGCPauseMillis should be "
! "greater than 0");
! }
! }
! if (!FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
! if (GCPauseIntervalMillis < 1) {
! vm_exit_during_initialization("GCPauseIntervalMillis should be "
! "greater than 0");
! }
! }
!
! // Then, if the pause time target parameter was not set, set it to
! // the default value.
! if (FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
! if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
! // The default pause time target in G1 is 200ms
! FLAG_SET_DEFAULT(MaxGCPauseMillis, 200);
! } else {
! // We do not allow the pause interval to be set without the
! // pause time target
! vm_exit_during_initialization("GCPauseIntervalMillis cannot be set "
! "without setting MaxGCPauseMillis");
! }
! }
!
! // Then, if the interval parameter was not set, set it according to
! // the pause time target (this will also deal with the case when the
! // pause time target is the default value).
! if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
! FLAG_SET_DEFAULT(GCPauseIntervalMillis, MaxGCPauseMillis + 1);
! }
!
! // Finally, make sure that the two parameters are consistent.
! if (MaxGCPauseMillis >= GCPauseIntervalMillis) {
! char buffer[256];
! jio_snprintf(buffer, 256,
! "MaxGCPauseMillis (%u) should be less than "
! "GCPauseIntervalMillis (%u)",
! MaxGCPauseMillis, GCPauseIntervalMillis);
! vm_exit_during_initialization(buffer);
! }
!
! double max_gc_time = (double) MaxGCPauseMillis / 1000.0;
! double time_slice = (double) GCPauseIntervalMillis / 1000.0;
! _mmu_tracker = new G1MMUTrackerQueue(time_slice, max_gc_time);
// start conservatively (around 50ms is about right)
_concurrent_mark_remark_times_ms->add(0.05);
_concurrent_mark_cleanup_times_ms->add(0.20);
- _tenuring_threshold = MaxTenuringThreshold;
-
- assert(GCTimeRatio > 0,
- "we should have set it to a default value set_g1_gc_flags() "
- "if a user set it to 0");
- _gc_overhead_perc = 100.0 * (1.0 / (1.0 + GCTimeRatio));
-
- uintx reserve_perc = G1ReservePercent;
- // Put an artificial ceiling on this so that it's not set to a silly value.
- if (reserve_perc > 50) {
- reserve_perc = 50;
- warning("G1ReservePercent is set to a value that is too large, "
- "it's been updated to " UINTX_FORMAT, reserve_perc);
- }
- _reserve_factor = (double) reserve_perc / 100.0;
- // This will be set when the heap is expanded
- // for the first time during initialization.
- _reserve_regions = 0;
-
- _ihop_control = create_ihop_control();
- }
-
- G1CollectorPolicy::~G1CollectorPolicy() {
- delete _ihop_control;
}
! double G1CollectorPolicy::get_new_prediction(TruncatedSeq const* seq) const {
! return _predictor.get_new_prediction(seq);
}
! size_t G1CollectorPolicy::get_new_size_prediction(TruncatedSeq const* seq) const {
return (size_t)get_new_prediction(seq);
}
! void G1CollectorPolicy::initialize_alignments() {
! _space_alignment = HeapRegion::GrainBytes;
! size_t card_table_alignment = CardTableRS::ct_max_alignment_constraint();
! size_t page_size = UseLargePages ? os::large_page_size() : os::vm_page_size();
! _heap_alignment = MAX3(card_table_alignment, _space_alignment, page_size);
! }
!
! G1CollectorState* G1CollectorPolicy::collector_state() const { return _g1->collector_state(); }
!
! void G1CollectorPolicy::post_heap_initialize() {
! uintx max_regions = G1CollectedHeap::heap()->max_regions();
! size_t max_young_size = (size_t)_young_gen_sizer->max_young_length(max_regions) * HeapRegion::GrainBytes;
! if (max_young_size != MaxNewSize) {
! FLAG_SET_ERGO(size_t, MaxNewSize, max_young_size);
! }
! }
!
! void G1CollectorPolicy::initialize_flags() {
! if (G1HeapRegionSize != HeapRegion::GrainBytes) {
! FLAG_SET_ERGO(size_t, G1HeapRegionSize, HeapRegion::GrainBytes);
! }
!
! if (SurvivorRatio < 1) {
! vm_exit_during_initialization("Invalid survivor ratio specified");
! }
! CollectorPolicy::initialize_flags();
! _young_gen_sizer = new G1YoungGenSizer(); // Must be after call to initialize_flags
! }
!
!
! void G1CollectorPolicy::init() {
! // Set aside an initial future to_space.
! _g1 = G1CollectedHeap::heap();
! _collection_set = _g1->collection_set();
! _collection_set->set_policy(this);
!
! assert(Heap_lock->owned_by_self(), "Locking discipline.");
!
! initialize_gc_policy_counters();
!
! if (adaptive_young_list_length()) {
! _young_list_fixed_length = 0;
! } else {
! _young_list_fixed_length = _young_gen_sizer->min_desired_young_length();
! }
! _free_regions_at_end_of_collection = _g1->num_free_regions();
!
! update_young_list_max_and_target_length();
! // We may immediately start allocating regions and placing them on the
! // collection set list. Initialize the per-collection set info
! _collection_set->start_incremental_building();
! }
!
! void G1CollectorPolicy::note_gc_start(uint num_active_workers) {
! phase_times()->note_gc_start(num_active_workers);
! }
!
! // Create the jstat counters for the policy.
! void G1CollectorPolicy::initialize_gc_policy_counters() {
! _gc_policy_counters = new GCPolicyCounters("GarbageFirst", 1, 3);
! }
!
! bool G1CollectorPolicy::predict_will_fit(uint young_length,
! double base_time_ms,
! uint base_free_regions,
! double target_pause_time_ms) const {
! if (young_length >= base_free_regions) {
! // end condition 1: not enough space for the young regions
! return false;
! }
!
! double accum_surv_rate = accum_yg_surv_rate_pred((int) young_length - 1);
! size_t bytes_to_copy =
! (size_t) (accum_surv_rate * (double) HeapRegion::GrainBytes);
! double copy_time_ms = predict_object_copy_time_ms(bytes_to_copy);
! double young_other_time_ms = predict_young_other_time_ms(young_length);
! double pause_time_ms = base_time_ms + copy_time_ms + young_other_time_ms;
! if (pause_time_ms > target_pause_time_ms) {
! // end condition 2: prediction is over the target pause time
! return false;
! }
!
! size_t free_bytes = (base_free_regions - young_length) * HeapRegion::GrainBytes;
!
! // When copying, we will likely need more bytes free than is live in the region.
! // Add some safety margin to factor in the confidence of our guess, and the
! // natural expected waste.
! // (100.0 / G1ConfidencePercent) is a scale factor that expresses the uncertainty
! // of the calculation: the lower the confidence, the more headroom.
! // (100 + TargetPLABWastePct) represents the increase in expected bytes during
! // copying due to anticipated waste in the PLABs.
! double safety_factor = (100.0 / G1ConfidencePercent) * (100 + TargetPLABWastePct) / 100.0;
! size_t expected_bytes_to_copy = (size_t)(safety_factor * bytes_to_copy);
!
! if (expected_bytes_to_copy > free_bytes) {
! // end condition 3: out-of-space
! return false;
! }
!
! // success!
! return true;
! }
!
! void G1CollectorPolicy::record_new_heap_size(uint new_number_of_regions) {
! // re-calculate the necessary reserve
! double reserve_regions_d = (double) new_number_of_regions * _reserve_factor;
! // We use ceiling so that if reserve_regions_d is > 0.0 (but
! // smaller than 1.0) we'll get 1.
! _reserve_regions = (uint) ceil(reserve_regions_d);
!
! _young_gen_sizer->heap_size_changed(new_number_of_regions);
!
! _ihop_control->update_target_occupancy(new_number_of_regions * HeapRegion::GrainBytes);
! }
!
! uint G1CollectorPolicy::calculate_young_list_desired_min_length(
! uint base_min_length) const {
! uint desired_min_length = 0;
! if (adaptive_young_list_length()) {
! if (_alloc_rate_ms_seq->num() > 3) {
! double now_sec = os::elapsedTime();
! double when_ms = _mmu_tracker->when_max_gc_sec(now_sec) * 1000.0;
! double alloc_rate_ms = predict_alloc_rate_ms();
! desired_min_length = (uint) ceil(alloc_rate_ms * when_ms);
! } else {
! // otherwise we don't have enough info to make the prediction
! }
! }
! desired_min_length += base_min_length;
! // make sure we don't go below any user-defined minimum bound
! return MAX2(_young_gen_sizer->min_desired_young_length(), desired_min_length);
! }
!
! uint G1CollectorPolicy::calculate_young_list_desired_max_length() const {
! // Here, we might want to also take into account any additional
! // constraints (i.e., user-defined minimum bound). Currently, we
! // effectively don't set this bound.
! return _young_gen_sizer->max_desired_young_length();
! }
!
! uint G1CollectorPolicy::update_young_list_max_and_target_length() {
! return update_young_list_max_and_target_length(predict_rs_lengths());
! }
!
! uint G1CollectorPolicy::update_young_list_max_and_target_length(size_t rs_lengths) {
! uint unbounded_target_length = update_young_list_target_length(rs_lengths);
! update_max_gc_locker_expansion();
! return unbounded_target_length;
! }
!
! uint G1CollectorPolicy::update_young_list_target_length(size_t rs_lengths) {
! YoungTargetLengths young_lengths = young_list_target_lengths(rs_lengths);
! _young_list_target_length = young_lengths.first;
! return young_lengths.second;
! }
!
! G1CollectorPolicy::YoungTargetLengths G1CollectorPolicy::young_list_target_lengths(size_t rs_lengths) const {
! YoungTargetLengths result;
!
! // Calculate the absolute and desired min bounds first.
!
! // This is how many young regions we already have (currently: the survivors).
! const uint base_min_length = _g1->young_list()->survivor_length();
! uint desired_min_length = calculate_young_list_desired_min_length(base_min_length);
! // This is the absolute minimum young length. Ensure that we
! // will at least have one eden region available for allocation.
! uint absolute_min_length = base_min_length + MAX2(_g1->young_list()->eden_length(), (uint)1);
! // If we shrank the young list target it should not shrink below the current size.
! desired_min_length = MAX2(desired_min_length, absolute_min_length);
! // Calculate the absolute and desired max bounds.
!
! uint desired_max_length = calculate_young_list_desired_max_length();
!
! uint young_list_target_length = 0;
! if (adaptive_young_list_length()) {
! if (collector_state()->gcs_are_young()) {
! young_list_target_length =
! calculate_young_list_target_length(rs_lengths,
! base_min_length,
! desired_min_length,
! desired_max_length);
! } else {
! // Don't calculate anything and let the code below bound it to
! // the desired_min_length, i.e., do the next GC as soon as
! // possible to maximize how many old regions we can add to it.
! }
! } else {
! // The user asked for a fixed young gen so we'll fix the young gen
! // whether the next GC is young or mixed.
! young_list_target_length = _young_list_fixed_length;
! }
!
! result.second = young_list_target_length;
!
! // We will try our best not to "eat" into the reserve.
! uint absolute_max_length = 0;
! if (_free_regions_at_end_of_collection > _reserve_regions) {
! absolute_max_length = _free_regions_at_end_of_collection - _reserve_regions;
! }
! if (desired_max_length > absolute_max_length) {
! desired_max_length = absolute_max_length;
! }
!
! // Make sure we don't go over the desired max length, nor under the
! // desired min length. In case they clash, desired_min_length wins
! // which is why that test is second.
! if (young_list_target_length > desired_max_length) {
! young_list_target_length = desired_max_length;
! }
! if (young_list_target_length < desired_min_length) {
! young_list_target_length = desired_min_length;
! }
!
! assert(young_list_target_length > base_min_length,
! "we should be able to allocate at least one eden region");
! assert(young_list_target_length >= absolute_min_length, "post-condition");
!
! result.first = young_list_target_length;
! return result;
! }
!
! uint
! G1CollectorPolicy::calculate_young_list_target_length(size_t rs_lengths,
! uint base_min_length,
! uint desired_min_length,
! uint desired_max_length) const {
! assert(adaptive_young_list_length(), "pre-condition");
! assert(collector_state()->gcs_are_young(), "only call this for young GCs");
!
! // In case some edge-condition makes the desired max length too small...
! if (desired_max_length <= desired_min_length) {
! return desired_min_length;
! }
!
! // We'll adjust min_young_length and max_young_length not to include
! // the already allocated young regions (i.e., so they reflect the
! // min and max eden regions we'll allocate). The base_min_length
! // will be reflected in the predictions by the
! // survivor_regions_evac_time prediction.
! assert(desired_min_length > base_min_length, "invariant");
! uint min_young_length = desired_min_length - base_min_length;
! assert(desired_max_length > base_min_length, "invariant");
! uint max_young_length = desired_max_length - base_min_length;
!
! double target_pause_time_ms = _mmu_tracker->max_gc_time() * 1000.0;
! double survivor_regions_evac_time = predict_survivor_regions_evac_time();
! size_t pending_cards = get_new_size_prediction(_pending_cards_seq);
! size_t adj_rs_lengths = rs_lengths + predict_rs_length_diff();
! size_t scanned_cards = predict_young_card_num(adj_rs_lengths);
! double base_time_ms =
! predict_base_elapsed_time_ms(pending_cards, scanned_cards) +
! survivor_regions_evac_time;
! uint available_free_regions = _free_regions_at_end_of_collection;
! uint base_free_regions = 0;
! if (available_free_regions > _reserve_regions) {
! base_free_regions = available_free_regions - _reserve_regions;
! }
!
! // Here, we will make sure that the shortest young length that
! // makes sense fits within the target pause time.
!
! if (predict_will_fit(min_young_length, base_time_ms,
! base_free_regions, target_pause_time_ms)) {
! // The shortest young length will fit into the target pause time;
! // we'll now check whether the absolute maximum number of young
! // regions will fit in the target pause time. If not, we'll do
! // a binary search between min_young_length and max_young_length.
! if (predict_will_fit(max_young_length, base_time_ms,
! base_free_regions, target_pause_time_ms)) {
! // The maximum young length will fit into the target pause time.
! // We are done so set min young length to the maximum length (as
! // the result is assumed to be returned in min_young_length).
! min_young_length = max_young_length;
! } else {
! // The maximum possible number of young regions will not fit within
! // the target pause time so we'll search for the optimal
! // length. The loop invariants are:
! //
! // min_young_length < max_young_length
! // min_young_length is known to fit into the target pause time
! // max_young_length is known not to fit into the target pause time
! //
! // Going into the loop we know the above hold as we've just
! // checked them. Every time around the loop we check whether
! // the middle value between min_young_length and
! // max_young_length fits into the target pause time. If it
! // does, it becomes the new min. If it doesn't, it becomes
! // the new max. This way we maintain the loop invariants.
!
! assert(min_young_length < max_young_length, "invariant");
! uint diff = (max_young_length - min_young_length) / 2;
! while (diff > 0) {
! uint young_length = min_young_length + diff;
! if (predict_will_fit(young_length, base_time_ms,
! base_free_regions, target_pause_time_ms)) {
! min_young_length = young_length;
! } else {
! max_young_length = young_length;
! }
! assert(min_young_length < max_young_length, "invariant");
! diff = (max_young_length - min_young_length) / 2;
! }
! // The results is min_young_length which, according to the
! // loop invariants, should fit within the target pause time.
!
! // These are the post-conditions of the binary search above:
! assert(min_young_length < max_young_length,
! "otherwise we should have discovered that max_young_length "
! "fits into the pause target and not done the binary search");
! assert(predict_will_fit(min_young_length, base_time_ms,
! base_free_regions, target_pause_time_ms),
! "min_young_length, the result of the binary search, should "
! "fit into the pause target");
! assert(!predict_will_fit(min_young_length + 1, base_time_ms,
! base_free_regions, target_pause_time_ms),
! "min_young_length, the result of the binary search, should be "
! "optimal, so no larger length should fit into the pause target");
! }
! } else {
! // Even the minimum length doesn't fit into the pause time
! // target, return it as the result nevertheless.
! }
! return base_min_length + min_young_length;
! }
!
! double G1CollectorPolicy::predict_survivor_regions_evac_time() const {
! double survivor_regions_evac_time = 0.0;
! for (HeapRegion * r = _g1->young_list()->first_survivor_region();
! r != NULL && r != _g1->young_list()->last_survivor_region()->get_next_young_region();
! r = r->get_next_young_region()) {
! survivor_regions_evac_time += predict_region_elapsed_time_ms(r, collector_state()->gcs_are_young());
! }
! return survivor_regions_evac_time;
! }
!
! void G1CollectorPolicy::revise_young_list_target_length_if_necessary(size_t rs_lengths) {
! guarantee( adaptive_young_list_length(), "should not call this otherwise" );
!
! if (rs_lengths > _rs_lengths_prediction) {
! // add 10% to avoid having to recalculate often
! size_t rs_lengths_prediction = rs_lengths * 1100 / 1000;
! update_rs_lengths_prediction(rs_lengths_prediction);
!
! update_young_list_max_and_target_length(rs_lengths_prediction);
! }
! }
!
! void G1CollectorPolicy::update_rs_lengths_prediction() {
! update_rs_lengths_prediction(predict_rs_lengths());
! }
!
! void G1CollectorPolicy::update_rs_lengths_prediction(size_t prediction) {
! if (collector_state()->gcs_are_young() && adaptive_young_list_length()) {
! _rs_lengths_prediction = prediction;
! }
! }
!
! #ifndef PRODUCT
! bool G1CollectorPolicy::verify_young_ages() {
! HeapRegion* head = _g1->young_list()->first_region();
! return
! verify_young_ages(head, _short_lived_surv_rate_group);
! // also call verify_young_ages on any additional surv rate groups
! }
!
! bool
! G1CollectorPolicy::verify_young_ages(HeapRegion* head,
! SurvRateGroup *surv_rate_group) {
! guarantee( surv_rate_group != NULL, "pre-condition" );
!
! const char* name = surv_rate_group->name();
! bool ret = true;
! int prev_age = -1;
!
! for (HeapRegion* curr = head;
! curr != NULL;
! curr = curr->get_next_young_region()) {
! SurvRateGroup* group = curr->surv_rate_group();
! if (group == NULL && !curr->is_survivor()) {
! log_error(gc, verify)("## %s: encountered NULL surv_rate_group", name);
! ret = false;
! }
!
! if (surv_rate_group == group) {
! int age = curr->age_in_surv_rate_group();
!
! if (age < 0) {
! log_error(gc, verify)("## %s: encountered negative age", name);
! ret = false;
! }
!
! if (age <= prev_age) {
! log_error(gc, verify)("## %s: region ages are not strictly increasing (%d, %d)", name, age, prev_age);
! ret = false;
! }
! prev_age = age;
! }
! }
!
! return ret;
! }
! #endif // PRODUCT
!
! void G1CollectorPolicy::record_full_collection_start() {
! _full_collection_start_sec = os::elapsedTime();
! // Release the future to-space so that it is available for compaction into.
! collector_state()->set_full_collection(true);
! }
!
! void G1CollectorPolicy::record_full_collection_end() {
! // Consider this like a collection pause for the purposes of allocation
! // since last pause.
! double end_sec = os::elapsedTime();
! double full_gc_time_sec = end_sec - _full_collection_start_sec;
! double full_gc_time_ms = full_gc_time_sec * 1000.0;
!
! update_recent_gc_times(end_sec, full_gc_time_ms);
!
! collector_state()->set_full_collection(false);
!
! // "Nuke" the heuristics that control the young/mixed GC
! // transitions and make sure we start with young GCs after the Full GC.
! collector_state()->set_gcs_are_young(true);
! collector_state()->set_last_young_gc(false);
! collector_state()->set_initiate_conc_mark_if_possible(need_to_start_conc_mark("end of Full GC", 0));
! collector_state()->set_during_initial_mark_pause(false);
! collector_state()->set_in_marking_window(false);
! collector_state()->set_in_marking_window_im(false);
!
! _short_lived_surv_rate_group->start_adding_regions();
! // also call this on any additional surv rate groups
!
! _free_regions_at_end_of_collection = _g1->num_free_regions();
! // Reset survivors SurvRateGroup.
! _survivor_surv_rate_group->reset();
! update_young_list_max_and_target_length();
! update_rs_lengths_prediction();
! cset_chooser()->clear();
!
! _bytes_allocated_in_old_since_last_gc = 0;
!
! record_pause(FullGC, _full_collection_start_sec, end_sec);
! }
!
! void G1CollectorPolicy::record_collection_pause_start(double start_time_sec) {
! // We only need to do this here as the policy will only be applied
! // to the GC we're about to start. so, no point is calculating this
! // every time we calculate / recalculate the target young length.
! update_survivors_policy();
!
! assert(_g1->used() == _g1->recalculate_used(),
! "sanity, used: " SIZE_FORMAT " recalculate_used: " SIZE_FORMAT,
! _g1->used(), _g1->recalculate_used());
!
! phase_times()->record_cur_collection_start_sec(start_time_sec);
! _pending_cards = _g1->pending_card_num();
!
! _collection_set->reset_bytes_used_before();
! _bytes_copied_during_gc = 0;
!
! collector_state()->set_last_gc_was_young(false);
!
! // do that for any other surv rate groups
! _short_lived_surv_rate_group->stop_adding_regions();
! _survivors_age_table.clear();
!
! assert( verify_young_ages(), "region age verification" );
! }
!
! void G1CollectorPolicy::record_concurrent_mark_init_end(double
! mark_init_elapsed_time_ms) {
! collector_state()->set_during_marking(true);
! assert(!collector_state()->initiate_conc_mark_if_possible(), "we should have cleared it by now");
! collector_state()->set_during_initial_mark_pause(false);
}
! void G1CollectorPolicy::record_concurrent_mark_remark_start() {
! _mark_remark_start_sec = os::elapsedTime();
! collector_state()->set_during_marking(false);
}
! void G1CollectorPolicy::record_concurrent_mark_remark_end() {
! double end_time_sec = os::elapsedTime();
! double elapsed_time_ms = (end_time_sec - _mark_remark_start_sec)*1000.0;
! _concurrent_mark_remark_times_ms->add(elapsed_time_ms);
! _prev_collection_pause_end_ms += elapsed_time_ms;
!
! record_pause(Remark, _mark_remark_start_sec, end_time_sec);
! }
!
! void G1CollectorPolicy::record_concurrent_mark_cleanup_start() {
! _mark_cleanup_start_sec = os::elapsedTime();
! }
!
! void G1CollectorPolicy::record_concurrent_mark_cleanup_completed() {
! bool should_continue_with_reclaim = next_gc_should_be_mixed("request last young-only gc",
! "skip last young-only gc");
! collector_state()->set_last_young_gc(should_continue_with_reclaim);
! // We skip the marking phase.
! if (!should_continue_with_reclaim) {
! abort_time_to_mixed_tracking();
! }
! collector_state()->set_in_marking_window(false);
}
! double G1CollectorPolicy::average_time_ms(G1GCPhaseTimes::GCParPhases phase) const {
! return phase_times()->average_time_ms(phase);
! }
!
! double G1CollectorPolicy::young_other_time_ms() const {
! return phase_times()->young_cset_choice_time_ms() +
! phase_times()->young_free_cset_time_ms();
! }
!
! double G1CollectorPolicy::non_young_other_time_ms() const {
! return phase_times()->non_young_cset_choice_time_ms() +
! phase_times()->non_young_free_cset_time_ms();
!
! }
!
! double G1CollectorPolicy::other_time_ms(double pause_time_ms) const {
! return pause_time_ms -
! average_time_ms(G1GCPhaseTimes::UpdateRS) -
! average_time_ms(G1GCPhaseTimes::ScanRS) -
! average_time_ms(G1GCPhaseTimes::ObjCopy) -
! average_time_ms(G1GCPhaseTimes::Termination);
! }
!
! double G1CollectorPolicy::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();
! }
!
! CollectionSetChooser* G1CollectorPolicy::cset_chooser() const {
! return _collection_set->cset_chooser();
! }
!
! bool G1CollectorPolicy::about_to_start_mixed_phase() const {
! return _g1->concurrent_mark()->cmThread()->during_cycle() || collector_state()->last_young_gc();
! }
!
! bool G1CollectorPolicy::need_to_start_conc_mark(const char* source, size_t alloc_word_size) {
! if (about_to_start_mixed_phase()) {
! return false;
! }
!
! size_t marking_initiating_used_threshold = _ihop_control->get_conc_mark_start_threshold();
!
! size_t cur_used_bytes = _g1->non_young_capacity_bytes();
! size_t alloc_byte_size = alloc_word_size * HeapWordSize;
! size_t marking_request_bytes = cur_used_bytes + alloc_byte_size;
!
! bool result = false;
! if (marking_request_bytes > marking_initiating_used_threshold) {
! result = collector_state()->gcs_are_young() && !collector_state()->last_young_gc();
! log_debug(gc, ergo, ihop)("%s occupancy: " SIZE_FORMAT "B allocation request: " SIZE_FORMAT "B threshold: " SIZE_FORMAT "B (%1.2f) source: %s",
! result ? "Request concurrent cycle initiation (occupancy higher than threshold)" : "Do not request concurrent cycle initiation (still doing mixed collections)",
! cur_used_bytes, alloc_byte_size, marking_initiating_used_threshold, (double) marking_initiating_used_threshold / _g1->capacity() * 100, source);
! }
!
! return result;
! }
!
! // Anything below that is considered to be zero
! #define MIN_TIMER_GRANULARITY 0.0000001
!
! void G1CollectorPolicy::record_collection_pause_end(double pause_time_ms, size_t cards_scanned, size_t heap_used_bytes_before_gc) {
! double end_time_sec = os::elapsedTime();
!
! size_t cur_used_bytes = _g1->used();
! assert(cur_used_bytes == _g1->recalculate_used(), "It should!");
! bool last_pause_included_initial_mark = false;
! bool update_stats = !_g1->evacuation_failed();
!
! NOT_PRODUCT(_short_lived_surv_rate_group->print());
!
! record_pause(young_gc_pause_kind(), end_time_sec - pause_time_ms / 1000.0, end_time_sec);
!
! last_pause_included_initial_mark = collector_state()->during_initial_mark_pause();
! if (last_pause_included_initial_mark) {
! record_concurrent_mark_init_end(0.0);
! } else {
! maybe_start_marking();
! }
!
! double app_time_ms = (phase_times()->cur_collection_start_sec() * 1000.0 - _prev_collection_pause_end_ms);
! if (app_time_ms < MIN_TIMER_GRANULARITY) {
! // This usually happens due to the timer not having the required
! // granularity. Some Linuxes are the usual culprits.
! // We'll just set it to something (arbitrarily) small.
! app_time_ms = 1.0;
! }
!
! if (update_stats) {
! // We maintain the invariant that all objects allocated by mutator
! // threads will be allocated out of eden regions. So, we can use
! // the eden region number allocated since the previous GC to
! // calculate the application's allocate rate. The only exception
! // to that is humongous objects that are allocated separately. But
! // given that humongous object allocations do not really affect
! // either the pause's duration nor when the next pause will take
! // place we can safely ignore them here.
! uint regions_allocated = _collection_set->eden_region_length();
! double alloc_rate_ms = (double) regions_allocated / app_time_ms;
! _alloc_rate_ms_seq->add(alloc_rate_ms);
!
! double interval_ms =
! (end_time_sec - _recent_prev_end_times_for_all_gcs_sec->oldest()) * 1000.0;
! update_recent_gc_times(end_time_sec, pause_time_ms);
! _recent_avg_pause_time_ratio = _recent_gc_times_ms->sum()/interval_ms;
! if (recent_avg_pause_time_ratio() < 0.0 ||
! (recent_avg_pause_time_ratio() - 1.0 > 0.0)) {
// Clip ratio between 0.0 and 1.0, and continue. This will be fixed in
// CR 6902692 by redoing the manner in which the ratio is incrementally computed.
if (_recent_avg_pause_time_ratio < 0.0) {
_recent_avg_pause_time_ratio = 0.0;
} else {
--- 85,144 ----
_mixed_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_per_byte_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_cost_per_byte_ms_during_cm_seq(new TruncatedSeq(TruncatedSeqLength)),
_constant_other_time_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
! _non_young_other_cost_per_region_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
_pending_cards_seq(new TruncatedSeq(TruncatedSeqLength)),
_rs_lengths_seq(new TruncatedSeq(TruncatedSeqLength)),
+ _recent_prev_end_times_for_all_gcs_sec(new TruncatedSeq(NumPrevPausesForHeuristics)) {
! // Seed sequences with initial values.
_recent_prev_end_times_for_all_gcs_sec->add(os::elapsedTime());
_prev_collection_pause_end_ms = os::elapsedTime() * 1000.0;
int index = MIN2(ParallelGCThreads - 1, 7u);
_rs_length_diff_seq->add(rs_length_diff_defaults[index]);
_cost_per_card_ms_seq->add(cost_per_card_ms_defaults[index]);
_cost_scan_hcc_seq->add(0.0);
! _young_cards_per_entry_ratio_seq->add(young_cards_per_entry_ratio_defaults[index]);
_cost_per_entry_ms_seq->add(cost_per_entry_ms_defaults[index]);
_cost_per_byte_ms_seq->add(cost_per_byte_ms_defaults[index]);
_constant_other_time_ms_seq->add(constant_other_time_ms_defaults[index]);
! _young_other_cost_per_region_ms_seq->add(young_other_cost_per_region_ms_defaults[index]);
! _non_young_other_cost_per_region_ms_seq->add(non_young_other_cost_per_region_ms_defaults[index]);
// start conservatively (around 50ms is about right)
_concurrent_mark_remark_times_ms->add(0.05);
_concurrent_mark_cleanup_times_ms->add(0.20);
}
! double G1Analytics::get_new_prediction(TruncatedSeq const* seq) const {
! return _predictor->get_new_prediction(seq);
}
! size_t G1Analytics::get_new_size_prediction(TruncatedSeq const* seq) const {
return (size_t)get_new_prediction(seq);
}
! int G1Analytics::num_alloc_rate_ms() const {
! return _alloc_rate_ms_seq->num();
}
! void G1Analytics::report_concurrent_mark_remark_times_ms(double ms) {
! _concurrent_mark_remark_times_ms->add(ms);
}
! void G1Analytics::report_alloc_rate_ms(double alloc_rate) {
! _alloc_rate_ms_seq->add(alloc_rate);
}
! void G1Analytics::compute_pause_time_ratio(double interval_ms, double pause_time_ms) {
! _recent_avg_pause_time_ratio = _recent_gc_times_ms->sum() / interval_ms;
! if (_recent_avg_pause_time_ratio < 0.0 ||
! (_recent_avg_pause_time_ratio - 1.0 > 0.0)) {
// Clip ratio between 0.0 and 1.0, and continue. This will be fixed in
// CR 6902692 by redoing the manner in which the ratio is incrementally computed.
if (_recent_avg_pause_time_ratio < 0.0) {
_recent_avg_pause_time_ratio = 0.0;
} else {
*** 891,1761 ****
// most recent interval, has the effect of smoothing over a possible transient 'burst'
// of more frequent pauses that don't really reflect a change in heap occupancy.
// This reduces the likelihood of a needless heap expansion being triggered.
_last_pause_time_ratio =
(pause_time_ms * _recent_prev_end_times_for_all_gcs_sec->num()) / interval_ms;
! }
!
! bool new_in_marking_window = collector_state()->in_marking_window();
! bool new_in_marking_window_im = false;
! if (last_pause_included_initial_mark) {
! new_in_marking_window = true;
! new_in_marking_window_im = true;
! }
!
! if (collector_state()->last_young_gc()) {
! // This is supposed to to be the "last young GC" before we start
! // doing mixed GCs. Here we decide whether to start mixed GCs or not.
! assert(!last_pause_included_initial_mark, "The last young GC is not allowed to be an initial mark GC");
!
! if (next_gc_should_be_mixed("start mixed GCs",
! "do not start mixed GCs")) {
! collector_state()->set_gcs_are_young(false);
! } else {
! // We aborted the mixed GC phase early.
! abort_time_to_mixed_tracking();
! }
!
! collector_state()->set_last_young_gc(false);
! }
!
! if (!collector_state()->last_gc_was_young()) {
! // This is a mixed GC. Here we decide whether to continue doing
! // mixed GCs or not.
! if (!next_gc_should_be_mixed("continue mixed GCs",
! "do not continue mixed GCs")) {
! collector_state()->set_gcs_are_young(true);
!
! maybe_start_marking();
! }
! }
!
! _short_lived_surv_rate_group->start_adding_regions();
! // Do that for any other surv rate groups
!
! double scan_hcc_time_ms = ConcurrentG1Refine::hot_card_cache_enabled() ? average_time_ms(G1GCPhaseTimes::ScanHCC) : 0.0;
! if (update_stats) {
! double cost_per_card_ms = 0.0;
! if (_pending_cards > 0) {
! cost_per_card_ms = (average_time_ms(G1GCPhaseTimes::UpdateRS) - scan_hcc_time_ms) / (double) _pending_cards;
_cost_per_card_ms_seq->add(cost_per_card_ms);
! }
! _cost_scan_hcc_seq->add(scan_hcc_time_ms);
! double cost_per_entry_ms = 0.0;
! if (cards_scanned > 10) {
! cost_per_entry_ms = average_time_ms(G1GCPhaseTimes::ScanRS) / (double) cards_scanned;
! if (collector_state()->last_gc_was_young()) {
_cost_per_entry_ms_seq->add(cost_per_entry_ms);
} else {
_mixed_cost_per_entry_ms_seq->add(cost_per_entry_ms);
}
! }
! if (_max_rs_lengths > 0) {
! double cards_per_entry_ratio =
! (double) cards_scanned / (double) _max_rs_lengths;
! if (collector_state()->last_gc_was_young()) {
_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
} else {
_mixed_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
}
! }
! // This is defensive. For a while _max_rs_lengths could get
! // smaller than _recorded_rs_lengths which was causing
! // rs_length_diff to get very large and mess up the RSet length
! // predictions. The reason was unsafe concurrent updates to the
! // _inc_cset_recorded_rs_lengths field which the code below guards
! // against (see CR 7118202). This bug has now been fixed (see CR
! // 7119027). However, I'm still worried that
! // _inc_cset_recorded_rs_lengths might still end up somewhat
! // inaccurate. The concurrent refinement thread calculates an
! // RSet's length concurrently with other CR threads updating it
! // which might cause it to calculate the length incorrectly (if,
! // say, it's in mid-coarsening). So I'll leave in the defensive
! // conditional below just in case.
! size_t rs_length_diff = 0;
! size_t recorded_rs_lengths = _collection_set->recorded_rs_lengths();
! if (_max_rs_lengths > recorded_rs_lengths) {
! rs_length_diff = _max_rs_lengths - recorded_rs_lengths;
! }
! _rs_length_diff_seq->add((double) rs_length_diff);
! size_t freed_bytes = heap_used_bytes_before_gc - cur_used_bytes;
! size_t copied_bytes = _collection_set->bytes_used_before() - freed_bytes;
! double cost_per_byte_ms = 0.0;
!
! if (copied_bytes > 0) {
! cost_per_byte_ms = average_time_ms(G1GCPhaseTimes::ObjCopy) / (double) copied_bytes;
! if (collector_state()->in_marking_window()) {
_cost_per_byte_ms_during_cm_seq->add(cost_per_byte_ms);
} else {
_cost_per_byte_ms_seq->add(cost_per_byte_ms);
}
- }
-
- if (_collection_set->young_region_length() > 0) {
- _young_other_cost_per_region_ms_seq->add(young_other_time_ms() /
- _collection_set->young_region_length());
- }
-
- if (_collection_set->old_region_length() > 0) {
- _non_young_other_cost_per_region_ms_seq->add(non_young_other_time_ms() /
- _collection_set->old_region_length());
- }
-
- _constant_other_time_ms_seq->add(constant_other_time_ms(pause_time_ms));
-
- _pending_cards_seq->add((double) _pending_cards);
- _rs_lengths_seq->add((double) _max_rs_lengths);
- }
-
- collector_state()->set_in_marking_window(new_in_marking_window);
- collector_state()->set_in_marking_window_im(new_in_marking_window_im);
- _free_regions_at_end_of_collection = _g1->num_free_regions();
- // IHOP control wants to know the expected young gen length if it were not
- // restrained by the heap reserve. Using the actual length would make the
- // prediction too small and the limit the young gen every time we get to the
- // predicted target occupancy.
- size_t last_unrestrained_young_length = update_young_list_max_and_target_length();
- update_rs_lengths_prediction();
-
- update_ihop_prediction(app_time_ms / 1000.0,
- _bytes_allocated_in_old_since_last_gc,
- last_unrestrained_young_length * HeapRegion::GrainBytes);
- _bytes_allocated_in_old_since_last_gc = 0;
-
- _ihop_control->send_trace_event(_g1->gc_tracer_stw());
-
- // Note that _mmu_tracker->max_gc_time() returns the time in seconds.
- double update_rs_time_goal_ms = _mmu_tracker->max_gc_time() * MILLIUNITS * G1RSetUpdatingPauseTimePercent / 100.0;
-
- if (update_rs_time_goal_ms < scan_hcc_time_ms) {
- log_debug(gc, ergo, refine)("Adjust concurrent refinement thresholds (scanning the HCC expected to take longer than Update RS time goal)."
- "Update RS time goal: %1.2fms Scan HCC time: %1.2fms",
- update_rs_time_goal_ms, scan_hcc_time_ms);
-
- update_rs_time_goal_ms = 0;
- } else {
- update_rs_time_goal_ms -= scan_hcc_time_ms;
- }
- adjust_concurrent_refinement(average_time_ms(G1GCPhaseTimes::UpdateRS) - scan_hcc_time_ms,
- phase_times()->sum_thread_work_items(G1GCPhaseTimes::UpdateRS),
- update_rs_time_goal_ms);
-
- cset_chooser()->verify();
}
! G1IHOPControl* G1CollectorPolicy::create_ihop_control() const {
! if (G1UseAdaptiveIHOP) {
! return new G1AdaptiveIHOPControl(InitiatingHeapOccupancyPercent,
! &_predictor,
! G1ReservePercent,
! G1HeapWastePercent);
! } else {
! return new G1StaticIHOPControl(InitiatingHeapOccupancyPercent);
! }
}
! void G1CollectorPolicy::update_ihop_prediction(double mutator_time_s,
! size_t mutator_alloc_bytes,
! size_t young_gen_size) {
! // Always try to update IHOP prediction. Even evacuation failures give information
! // about e.g. whether to start IHOP earlier next time.
!
! // Avoid using really small application times that might create samples with
! // very high or very low values. They may be caused by e.g. back-to-back gcs.
! double const min_valid_time = 1e-6;
!
! bool report = false;
!
! double marking_to_mixed_time = -1.0;
! if (!collector_state()->last_gc_was_young() && _initial_mark_to_mixed.has_result()) {
! marking_to_mixed_time = _initial_mark_to_mixed.last_marking_time();
! assert(marking_to_mixed_time > 0.0,
! "Initial mark to mixed time must be larger than zero but is %.3f",
! marking_to_mixed_time);
! if (marking_to_mixed_time > min_valid_time) {
! _ihop_control->update_marking_length(marking_to_mixed_time);
! report = true;
! }
! }
!
! // As an approximation for the young gc promotion rates during marking we use
! // all of them. In many applications there are only a few if any young gcs during
! // marking, which makes any prediction useless. This increases the accuracy of the
! // prediction.
! if (collector_state()->last_gc_was_young() && mutator_time_s > min_valid_time) {
! _ihop_control->update_allocation_info(mutator_time_s, mutator_alloc_bytes, young_gen_size);
! report = true;
! }
!
! if (report) {
! report_ihop_statistics();
! }
}
! void G1CollectorPolicy::report_ihop_statistics() {
! _ihop_control->print();
}
! void G1CollectorPolicy::print_phases() {
! phase_times()->print();
}
! void G1CollectorPolicy::adjust_concurrent_refinement(double update_rs_time,
! double update_rs_processed_buffers,
! double goal_ms) {
! DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
! ConcurrentG1Refine *cg1r = G1CollectedHeap::heap()->concurrent_g1_refine();
!
! if (G1UseAdaptiveConcRefinement) {
! const int k_gy = 3, k_gr = 6;
! const double inc_k = 1.1, dec_k = 0.9;
!
! size_t g = cg1r->green_zone();
! if (update_rs_time > goal_ms) {
! g = (size_t)(g * dec_k); // Can become 0, that's OK. That would mean a mutator-only processing.
! } else {
! if (update_rs_time < goal_ms && update_rs_processed_buffers > g) {
! g = (size_t)MAX2(g * inc_k, g + 1.0);
! }
! }
! // Change the refinement threads params
! cg1r->set_green_zone(g);
! cg1r->set_yellow_zone(g * k_gy);
! cg1r->set_red_zone(g * k_gr);
! cg1r->reinitialize_threads();
!
! size_t processing_threshold_delta = MAX2<size_t>(cg1r->green_zone() * _predictor.sigma(), 1);
! size_t processing_threshold = MIN2(cg1r->green_zone() + processing_threshold_delta,
! cg1r->yellow_zone());
! // Change the barrier params
! dcqs.set_process_completed_threshold((int)processing_threshold);
! dcqs.set_max_completed_queue((int)cg1r->red_zone());
! }
!
! size_t curr_queue_size = dcqs.completed_buffers_num();
! if (curr_queue_size >= cg1r->yellow_zone()) {
! dcqs.set_completed_queue_padding(curr_queue_size);
! } else {
! dcqs.set_completed_queue_padding(0);
! }
! dcqs.notify_if_necessary();
}
! size_t G1CollectorPolicy::predict_rs_lengths() const {
! return get_new_size_prediction(_rs_lengths_seq);
! }
!
! size_t G1CollectorPolicy::predict_rs_length_diff() const {
return get_new_size_prediction(_rs_length_diff_seq);
}
! double G1CollectorPolicy::predict_alloc_rate_ms() const {
return get_new_prediction(_alloc_rate_ms_seq);
}
! double G1CollectorPolicy::predict_cost_per_card_ms() const {
return get_new_prediction(_cost_per_card_ms_seq);
}
! double G1CollectorPolicy::predict_scan_hcc_ms() const {
return get_new_prediction(_cost_scan_hcc_seq);
}
! double G1CollectorPolicy::predict_rs_update_time_ms(size_t pending_cards) const {
return pending_cards * predict_cost_per_card_ms() + predict_scan_hcc_ms();
}
! double G1CollectorPolicy::predict_young_cards_per_entry_ratio() const {
return get_new_prediction(_young_cards_per_entry_ratio_seq);
}
! double G1CollectorPolicy::predict_mixed_cards_per_entry_ratio() const {
if (_mixed_cards_per_entry_ratio_seq->num() < 2) {
return predict_young_cards_per_entry_ratio();
} else {
return get_new_prediction(_mixed_cards_per_entry_ratio_seq);
}
}
! size_t G1CollectorPolicy::predict_young_card_num(size_t rs_length) const {
return (size_t) (rs_length * predict_young_cards_per_entry_ratio());
}
! size_t G1CollectorPolicy::predict_non_young_card_num(size_t rs_length) const {
! return (size_t)(rs_length * predict_mixed_cards_per_entry_ratio());
! }
!
! double G1CollectorPolicy::predict_rs_scan_time_ms(size_t card_num) const {
! if (collector_state()->gcs_are_young()) {
return card_num * get_new_prediction(_cost_per_entry_ms_seq);
} else {
return predict_mixed_rs_scan_time_ms(card_num);
}
}
! double G1CollectorPolicy::predict_mixed_rs_scan_time_ms(size_t card_num) const {
if (_mixed_cost_per_entry_ms_seq->num() < 3) {
return card_num * get_new_prediction(_cost_per_entry_ms_seq);
} else {
return card_num * get_new_prediction(_mixed_cost_per_entry_ms_seq);
}
}
! double G1CollectorPolicy::predict_object_copy_time_ms_during_cm(size_t bytes_to_copy) const {
if (_cost_per_byte_ms_during_cm_seq->num() < 3) {
return (1.1 * bytes_to_copy) * get_new_prediction(_cost_per_byte_ms_seq);
} else {
return bytes_to_copy * get_new_prediction(_cost_per_byte_ms_during_cm_seq);
}
}
! double G1CollectorPolicy::predict_object_copy_time_ms(size_t bytes_to_copy) const {
! if (collector_state()->during_concurrent_mark()) {
return predict_object_copy_time_ms_during_cm(bytes_to_copy);
} else {
return bytes_to_copy * get_new_prediction(_cost_per_byte_ms_seq);
}
}
! double G1CollectorPolicy::predict_constant_other_time_ms() const {
return get_new_prediction(_constant_other_time_ms_seq);
}
! double G1CollectorPolicy::predict_young_other_time_ms(size_t young_num) const {
return young_num * get_new_prediction(_young_other_cost_per_region_ms_seq);
}
! double G1CollectorPolicy::predict_non_young_other_time_ms(size_t non_young_num) const {
return non_young_num * get_new_prediction(_non_young_other_cost_per_region_ms_seq);
}
! double G1CollectorPolicy::predict_remark_time_ms() const {
return get_new_prediction(_concurrent_mark_remark_times_ms);
}
! double G1CollectorPolicy::predict_cleanup_time_ms() const {
return get_new_prediction(_concurrent_mark_cleanup_times_ms);
}
! double G1CollectorPolicy::predict_yg_surv_rate(int age, SurvRateGroup* surv_rate_group) const {
! TruncatedSeq* seq = surv_rate_group->get_seq(age);
! guarantee(seq->num() > 0, "There should be some young gen survivor samples available. Tried to access with age %d", age);
! double pred = get_new_prediction(seq);
! if (pred > 1.0) {
! pred = 1.0;
! }
! return pred;
! }
!
! double G1CollectorPolicy::predict_yg_surv_rate(int age) const {
! return predict_yg_surv_rate(age, _short_lived_surv_rate_group);
! }
!
! double G1CollectorPolicy::accum_yg_surv_rate_pred(int age) const {
! return _short_lived_surv_rate_group->accum_surv_rate_pred(age);
! }
!
! double G1CollectorPolicy::predict_base_elapsed_time_ms(size_t pending_cards,
! size_t scanned_cards) const {
! 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) const {
! size_t rs_length = predict_rs_lengths() + predict_rs_length_diff();
! size_t card_num;
! if (collector_state()->gcs_are_young()) {
! card_num = predict_young_card_num(rs_length);
! } else {
! card_num = predict_non_young_card_num(rs_length);
! }
! return predict_base_elapsed_time_ms(pending_cards, card_num);
}
! size_t G1CollectorPolicy::predict_bytes_to_copy(HeapRegion* hr) const {
! 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) (hr->used() * yg_surv_rate);
! }
! return bytes_to_copy;
}
! double G1CollectorPolicy::predict_region_elapsed_time_ms(HeapRegion* hr,
! bool for_young_gc) const {
! size_t rs_length = hr->rem_set()->occupied();
! size_t card_num;
!
! // 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);
! }
! size_t bytes_to_copy = predict_bytes_to_copy(hr);
!
! double region_elapsed_time_ms =
! predict_rs_scan_time_ms(card_num) +
! predict_object_copy_time_ms(bytes_to_copy);
!
! // 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 {
! region_elapsed_time_ms += predict_non_young_other_time_ms(1);
! }
! return region_elapsed_time_ms;
! }
!
! void G1CollectorPolicy::update_recent_gc_times(double end_time_sec,
! double elapsed_ms) {
! _recent_gc_times_ms->add(elapsed_ms);
_recent_prev_end_times_for_all_gcs_sec->add(end_time_sec);
_prev_collection_pause_end_ms = end_time_sec * 1000.0;
}
! void G1CollectorPolicy::clear_ratio_check_data() {
! _ratio_over_threshold_count = 0;
! _ratio_over_threshold_sum = 0.0;
! _pauses_since_start = 0;
! }
!
! size_t G1CollectorPolicy::expansion_amount() {
! double recent_gc_overhead = recent_avg_pause_time_ratio() * 100.0;
! double last_gc_overhead = _last_pause_time_ratio * 100.0;
! double threshold = _gc_overhead_perc;
! size_t expand_bytes = 0;
!
! // If the heap is at less than half its maximum size, scale the threshold down,
! // to a limit of 1. Thus the smaller the heap is, the more likely it is to expand,
! // though the scaling code will likely keep the increase small.
! if (_g1->capacity() <= _g1->max_capacity() / 2) {
! threshold *= (double)_g1->capacity() / (double)(_g1->max_capacity() / 2);
! threshold = MAX2(threshold, 1.0);
! }
!
! // If the last GC time ratio is over the threshold, increment the count of
! // times it has been exceeded, and add this ratio to the sum of exceeded
! // ratios.
! if (last_gc_overhead > threshold) {
! _ratio_over_threshold_count++;
! _ratio_over_threshold_sum += last_gc_overhead;
! }
!
! // Check if we've had enough GC time ratio checks that were over the
! // threshold to trigger an expansion. We'll also expand if we've
! // reached the end of the history buffer and the average of all entries
! // is still over the threshold. This indicates a smaller number of GCs were
! // long enough to make the average exceed the threshold.
! bool filled_history_buffer = _pauses_since_start == NumPrevPausesForHeuristics;
! if ((_ratio_over_threshold_count == MinOverThresholdForGrowth) ||
! (filled_history_buffer && (recent_gc_overhead > threshold))) {
! size_t min_expand_bytes = HeapRegion::GrainBytes;
! size_t reserved_bytes = _g1->max_capacity();
! size_t committed_bytes = _g1->capacity();
! size_t uncommitted_bytes = reserved_bytes - committed_bytes;
! size_t expand_bytes_via_pct =
! uncommitted_bytes * G1ExpandByPercentOfAvailable / 100;
! double scale_factor = 1.0;
!
! // If the current size is less than 1/4 of the Initial heap size, expand
! // by half of the delta between the current and Initial sizes. IE, grow
! // back quickly.
! //
! // Otherwise, take the current size, or G1ExpandByPercentOfAvailable % of
! // the available expansion space, whichever is smaller, as the base
! // expansion size. Then possibly scale this size according to how much the
! // threshold has (on average) been exceeded by. If the delta is small
! // (less than the StartScaleDownAt value), scale the size down linearly, but
! // not by less than MinScaleDownFactor. If the delta is large (greater than
! // the StartScaleUpAt value), scale up, but adding no more than MaxScaleUpFactor
! // times the base size. The scaling will be linear in the range from
! // StartScaleUpAt to (StartScaleUpAt + ScaleUpRange). In other words,
! // ScaleUpRange sets the rate of scaling up.
! if (committed_bytes < InitialHeapSize / 4) {
! expand_bytes = (InitialHeapSize - committed_bytes) / 2;
! } else {
! double const MinScaleDownFactor = 0.2;
! double const MaxScaleUpFactor = 2;
! double const StartScaleDownAt = _gc_overhead_perc;
! double const StartScaleUpAt = _gc_overhead_perc * 1.5;
! double const ScaleUpRange = _gc_overhead_perc * 2.0;
!
! double ratio_delta;
! if (filled_history_buffer) {
! ratio_delta = recent_gc_overhead - threshold;
! } else {
! ratio_delta = (_ratio_over_threshold_sum/_ratio_over_threshold_count) - threshold;
! }
!
! expand_bytes = MIN2(expand_bytes_via_pct, committed_bytes);
! if (ratio_delta < StartScaleDownAt) {
! scale_factor = ratio_delta / StartScaleDownAt;
! scale_factor = MAX2(scale_factor, MinScaleDownFactor);
! } else if (ratio_delta > StartScaleUpAt) {
! scale_factor = 1 + ((ratio_delta - StartScaleUpAt) / ScaleUpRange);
! scale_factor = MIN2(scale_factor, MaxScaleUpFactor);
! }
! }
!
! log_debug(gc, ergo, heap)("Attempt heap expansion (recent GC overhead higher than threshold after GC) "
! "recent GC overhead: %1.2f %% threshold: %1.2f %% uncommitted: " SIZE_FORMAT "B base expansion amount and scale: " SIZE_FORMAT "B (%1.2f%%)",
! recent_gc_overhead, threshold, uncommitted_bytes, expand_bytes, scale_factor * 100);
!
! expand_bytes = static_cast<size_t>(expand_bytes * scale_factor);
!
! // Ensure the expansion size is at least the minimum growth amount
! // and at most the remaining uncommitted byte size.
! expand_bytes = MAX2(expand_bytes, min_expand_bytes);
! expand_bytes = MIN2(expand_bytes, uncommitted_bytes);
!
! clear_ratio_check_data();
! } else {
! // An expansion was not triggered. If we've started counting, increment
! // the number of checks we've made in the current window. If we've
! // reached the end of the window without resizing, clear the counters to
! // start again the next time we see a ratio above the threshold.
! if (_ratio_over_threshold_count > 0) {
! _pauses_since_start++;
! if (_pauses_since_start > NumPrevPausesForHeuristics) {
! clear_ratio_check_data();
! }
! }
! }
!
! return expand_bytes;
! }
!
! void G1CollectorPolicy::print_yg_surv_rate_info() const {
! #ifndef PRODUCT
! _short_lived_surv_rate_group->print_surv_rate_summary();
! // add this call for any other surv rate groups
! #endif // PRODUCT
! }
!
! bool G1CollectorPolicy::is_young_list_full() const {
! uint young_list_length = _g1->young_list()->length();
! uint young_list_target_length = _young_list_target_length;
! return young_list_length >= young_list_target_length;
! }
!
! bool G1CollectorPolicy::can_expand_young_list() const {
! uint young_list_length = _g1->young_list()->length();
! uint young_list_max_length = _young_list_max_length;
! return young_list_length < young_list_max_length;
! }
!
! bool G1CollectorPolicy::adaptive_young_list_length() const {
! return _young_gen_sizer->adaptive_young_list_length();
! }
!
! void G1CollectorPolicy::update_max_gc_locker_expansion() {
! uint expansion_region_num = 0;
! if (GCLockerEdenExpansionPercent > 0) {
! double perc = (double) GCLockerEdenExpansionPercent / 100.0;
! double expansion_region_num_d = perc * (double) _young_list_target_length;
! // We use ceiling so that if expansion_region_num_d is > 0.0 (but
! // less than 1.0) we'll get 1.
! expansion_region_num = (uint) ceil(expansion_region_num_d);
! } else {
! assert(expansion_region_num == 0, "sanity");
! }
! _young_list_max_length = _young_list_target_length + expansion_region_num;
! assert(_young_list_target_length <= _young_list_max_length, "post-condition");
! }
!
! // Calculates survivor space parameters.
! void G1CollectorPolicy::update_survivors_policy() {
! double max_survivor_regions_d =
! (double) _young_list_target_length / (double) SurvivorRatio;
! // We use ceiling so that if max_survivor_regions_d is > 0.0 (but
! // smaller than 1.0) we'll get 1.
! _max_survivor_regions = (uint) ceil(max_survivor_regions_d);
!
! _tenuring_threshold = _survivors_age_table.compute_tenuring_threshold(
! HeapRegion::GrainWords * _max_survivor_regions, counters());
! }
!
! bool G1CollectorPolicy::force_initial_mark_if_outside_cycle(GCCause::Cause gc_cause) {
! // We actually check whether we are marking here and not if we are in a
! // reclamation phase. This means that we will schedule a concurrent mark
! // even while we are still in the process of reclaiming memory.
! bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
! if (!during_cycle) {
! log_debug(gc, ergo)("Request concurrent cycle initiation (requested by GC cause). GC cause: %s", GCCause::to_string(gc_cause));
! collector_state()->set_initiate_conc_mark_if_possible(true);
! return true;
! } else {
! log_debug(gc, ergo)("Do not request concurrent cycle initiation (concurrent cycle already in progress). GC cause: %s", GCCause::to_string(gc_cause));
! return false;
! }
! }
!
! void G1CollectorPolicy::initiate_conc_mark() {
! collector_state()->set_during_initial_mark_pause(true);
! collector_state()->set_initiate_conc_mark_if_possible(false);
! }
!
! void G1CollectorPolicy::decide_on_conc_mark_initiation() {
! // We are about to decide on whether this pause will be an
! // initial-mark pause.
!
! // First, collector_state()->during_initial_mark_pause() should not be already set. We
! // will set it here if we have to. However, it should be cleared by
! // the end of the pause (it's only set for the duration of an
! // initial-mark pause).
! assert(!collector_state()->during_initial_mark_pause(), "pre-condition");
!
! if (collector_state()->initiate_conc_mark_if_possible()) {
! // We had noticed on a previous pause that the heap occupancy has
! // gone over the initiating threshold and we should start a
! // concurrent marking cycle. So we might initiate one.
!
! if (!about_to_start_mixed_phase() && collector_state()->gcs_are_young()) {
! // Initiate a new initial mark if there is no marking or reclamation going on.
! initiate_conc_mark();
! log_debug(gc, ergo)("Initiate concurrent cycle (concurrent cycle initiation requested)");
! } else if (_g1->is_user_requested_concurrent_full_gc(_g1->gc_cause())) {
! // Initiate a user requested initial mark. An initial mark must be young only
! // GC, so the collector state must be updated to reflect this.
! collector_state()->set_gcs_are_young(true);
! collector_state()->set_last_young_gc(false);
!
! abort_time_to_mixed_tracking();
! initiate_conc_mark();
! log_debug(gc, ergo)("Initiate concurrent cycle (user requested concurrent cycle)");
! } else {
! // The concurrent marking thread is still finishing up the
! // previous cycle. If we start one right now the two cycles
! // overlap. In particular, the concurrent marking thread might
! // be in the process of clearing the next marking bitmap (which
! // we will use for the next cycle if we start one). Starting a
! // cycle now will be bad given that parts of the marking
! // information might get cleared by the marking thread. And we
! // cannot wait for the marking thread to finish the cycle as it
! // periodically yields while clearing the next marking bitmap
! // and, if it's in a yield point, it's waiting for us to
! // finish. So, at this point we will not start a cycle and we'll
! // let the concurrent marking thread complete the last one.
! log_debug(gc, ergo)("Do not initiate concurrent cycle (concurrent cycle already in progress)");
! }
! }
! }
!
! class ParKnownGarbageHRClosure: public HeapRegionClosure {
! G1CollectedHeap* _g1h;
! CSetChooserParUpdater _cset_updater;
!
! public:
! ParKnownGarbageHRClosure(CollectionSetChooser* hrSorted,
! uint chunk_size) :
! _g1h(G1CollectedHeap::heap()),
! _cset_updater(hrSorted, true /* parallel */, chunk_size) { }
!
! bool doHeapRegion(HeapRegion* r) {
! // Do we have any marking information for this region?
! if (r->is_marked()) {
! // We will skip any region that's currently used as an old GC
! // alloc region (we should not consider those for collection
! // before we fill them up).
! if (_cset_updater.should_add(r) && !_g1h->is_old_gc_alloc_region(r)) {
! _cset_updater.add_region(r);
! }
! }
! return false;
! }
! };
!
! class ParKnownGarbageTask: public AbstractGangTask {
! CollectionSetChooser* _hrSorted;
! uint _chunk_size;
! G1CollectedHeap* _g1;
! HeapRegionClaimer _hrclaimer;
!
! public:
! ParKnownGarbageTask(CollectionSetChooser* hrSorted, uint chunk_size, uint n_workers) :
! AbstractGangTask("ParKnownGarbageTask"),
! _hrSorted(hrSorted), _chunk_size(chunk_size),
! _g1(G1CollectedHeap::heap()), _hrclaimer(n_workers) {}
!
! void work(uint worker_id) {
! ParKnownGarbageHRClosure parKnownGarbageCl(_hrSorted, _chunk_size);
! _g1->heap_region_par_iterate(&parKnownGarbageCl, worker_id, &_hrclaimer);
! }
! };
!
! uint G1CollectorPolicy::calculate_parallel_work_chunk_size(uint n_workers, uint n_regions) const {
! assert(n_workers > 0, "Active gc workers should be greater than 0");
! const uint overpartition_factor = 4;
! const uint min_chunk_size = MAX2(n_regions / n_workers, 1U);
! return MAX2(n_regions / (n_workers * overpartition_factor), min_chunk_size);
! }
!
! void G1CollectorPolicy::record_concurrent_mark_cleanup_end() {
! cset_chooser()->clear();
!
! WorkGang* workers = _g1->workers();
! uint n_workers = workers->active_workers();
!
! uint n_regions = _g1->num_regions();
! uint chunk_size = calculate_parallel_work_chunk_size(n_workers, n_regions);
! cset_chooser()->prepare_for_par_region_addition(n_workers, n_regions, chunk_size);
! ParKnownGarbageTask par_known_garbage_task(cset_chooser(), chunk_size, n_workers);
! workers->run_task(&par_known_garbage_task);
!
! cset_chooser()->sort_regions();
!
! double end_sec = os::elapsedTime();
! double elapsed_time_ms = (end_sec - _mark_cleanup_start_sec) * 1000.0;
! _concurrent_mark_cleanup_times_ms->add(elapsed_time_ms);
! _prev_collection_pause_end_ms += elapsed_time_ms;
!
! record_pause(Cleanup, _mark_cleanup_start_sec, end_sec);
! }
!
! double G1CollectorPolicy::reclaimable_bytes_perc(size_t reclaimable_bytes) const {
! // Returns the given amount of reclaimable bytes (that represents
! // the amount of reclaimable space still to be collected) as a
! // percentage of the current heap capacity.
! size_t capacity_bytes = _g1->capacity();
! return (double) reclaimable_bytes * 100.0 / (double) capacity_bytes;
! }
!
! void G1CollectorPolicy::maybe_start_marking() {
! if (need_to_start_conc_mark("end of GC")) {
! // Note: this might have already been set, if during the last
! // pause we decided to start a cycle but at the beginning of
! // this pause we decided to postpone it. That's OK.
! collector_state()->set_initiate_conc_mark_if_possible(true);
! }
! }
!
! G1CollectorPolicy::PauseKind G1CollectorPolicy::young_gc_pause_kind() const {
! assert(!collector_state()->full_collection(), "must be");
! if (collector_state()->during_initial_mark_pause()) {
! assert(collector_state()->last_gc_was_young(), "must be");
! assert(!collector_state()->last_young_gc(), "must be");
! return InitialMarkGC;
! } else if (collector_state()->last_young_gc()) {
! assert(!collector_state()->during_initial_mark_pause(), "must be");
! assert(collector_state()->last_gc_was_young(), "must be");
! return LastYoungGC;
! } else if (!collector_state()->last_gc_was_young()) {
! assert(!collector_state()->during_initial_mark_pause(), "must be");
! assert(!collector_state()->last_young_gc(), "must be");
! return MixedGC;
! } else {
! assert(collector_state()->last_gc_was_young(), "must be");
! assert(!collector_state()->during_initial_mark_pause(), "must be");
! assert(!collector_state()->last_young_gc(), "must be");
! return YoungOnlyGC;
! }
! }
!
! void G1CollectorPolicy::record_pause(PauseKind kind, double start, double end) {
! // Manage the MMU tracker. For some reason it ignores Full GCs.
! if (kind != FullGC) {
! _mmu_tracker->add_pause(start, end);
! }
! // Manage the mutator time tracking from initial mark to first mixed gc.
! switch (kind) {
! case FullGC:
! abort_time_to_mixed_tracking();
! break;
! case Cleanup:
! case Remark:
! case YoungOnlyGC:
! case LastYoungGC:
! _initial_mark_to_mixed.add_pause(end - start);
! break;
! case InitialMarkGC:
! _initial_mark_to_mixed.record_initial_mark_end(end);
! break;
! case MixedGC:
! _initial_mark_to_mixed.record_mixed_gc_start(start);
! break;
! default:
! ShouldNotReachHere();
! }
! }
!
! void G1CollectorPolicy::abort_time_to_mixed_tracking() {
! _initial_mark_to_mixed.reset();
! }
!
! bool G1CollectorPolicy::next_gc_should_be_mixed(const char* true_action_str,
! const char* false_action_str) const {
! if (cset_chooser()->is_empty()) {
! log_debug(gc, ergo)("%s (candidate old regions not available)", false_action_str);
! return false;
! }
!
! // Is the amount of uncollected reclaimable space above G1HeapWastePercent?
! size_t reclaimable_bytes = cset_chooser()->remaining_reclaimable_bytes();
! double reclaimable_perc = reclaimable_bytes_perc(reclaimable_bytes);
! double threshold = (double) G1HeapWastePercent;
! if (reclaimable_perc <= threshold) {
! log_debug(gc, ergo)("%s (reclaimable percentage not over threshold). candidate old regions: %u reclaimable: " SIZE_FORMAT " (%1.2f) threshold: " UINTX_FORMAT,
! false_action_str, cset_chooser()->remaining_regions(), reclaimable_bytes, reclaimable_perc, G1HeapWastePercent);
! return false;
! }
! log_debug(gc, ergo)("%s (candidate old regions available). candidate old regions: %u reclaimable: " SIZE_FORMAT " (%1.2f) threshold: " UINTX_FORMAT,
! true_action_str, cset_chooser()->remaining_regions(), reclaimable_bytes, reclaimable_perc, G1HeapWastePercent);
! return true;
! }
!
! uint G1CollectorPolicy::calc_min_old_cset_length() const {
! // The min old CSet region bound is based on the maximum desired
! // number of mixed GCs after a cycle. I.e., even if some old regions
! // look expensive, we should add them to the CSet anyway to make
! // sure we go through the available old regions in no more than the
! // maximum desired number of mixed GCs.
! //
! // The calculation is based on the number of marked regions we added
! // to the CSet chooser in the first place, not how many remain, so
! // that the result is the same during all mixed GCs that follow a cycle.
!
! const size_t region_num = (size_t) cset_chooser()->length();
! const size_t gc_num = (size_t) MAX2(G1MixedGCCountTarget, (uintx) 1);
! size_t result = region_num / gc_num;
! // emulate ceiling
! if (result * gc_num < region_num) {
! result += 1;
! }
! return (uint) result;
! }
!
! uint G1CollectorPolicy::calc_max_old_cset_length() const {
! // The max old CSet region bound is based on the threshold expressed
! // as a percentage of the heap size. I.e., it should bound the
! // number of old regions added to the CSet irrespective of how many
! // of them are available.
!
! const G1CollectedHeap* g1h = G1CollectedHeap::heap();
! const size_t region_num = g1h->num_regions();
! const size_t perc = (size_t) G1OldCSetRegionThresholdPercent;
! size_t result = region_num * perc / 100;
! // emulate ceiling
! if (100 * result < region_num * perc) {
! result += 1;
! }
! return (uint) result;
! }
!
! void G1CollectorPolicy::finalize_collection_set(double target_pause_time_ms) {
! double time_remaining_ms = _collection_set->finalize_young_part(target_pause_time_ms);
! _collection_set->finalize_old_part(time_remaining_ms);
}
--- 152,329 ----
// most recent interval, has the effect of smoothing over a possible transient 'burst'
// of more frequent pauses that don't really reflect a change in heap occupancy.
// This reduces the likelihood of a needless heap expansion being triggered.
_last_pause_time_ratio =
(pause_time_ms * _recent_prev_end_times_for_all_gcs_sec->num()) / interval_ms;
! }
! void G1Analytics::report_cost_per_card_ms(double cost_per_card_ms) {
_cost_per_card_ms_seq->add(cost_per_card_ms);
! }
! void G1Analytics::report_cost_scan_hcc(double cost_scan_hcc) {
! _cost_scan_hcc_seq->add(cost_scan_hcc);
! }
!
! void G1Analytics::report_cost_per_entry_ms(double cost_per_entry_ms, bool last_gc_was_young) {
! if (last_gc_was_young) {
_cost_per_entry_ms_seq->add(cost_per_entry_ms);
} else {
_mixed_cost_per_entry_ms_seq->add(cost_per_entry_ms);
}
! }
! void G1Analytics::report_cards_per_entry_ratio(double cards_per_entry_ratio, bool last_gc_was_young) {
! if (last_gc_was_young) {
_young_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
} else {
_mixed_cards_per_entry_ratio_seq->add(cards_per_entry_ratio);
}
! }
! void G1Analytics::report_rs_length_diff(double rs_length_diff) {
! _rs_length_diff_seq->add(rs_length_diff);
! }
! void G1Analytics::report_cost_per_byte_ms(double cost_per_byte_ms, bool in_marking_window) {
! if (in_marking_window) {
_cost_per_byte_ms_during_cm_seq->add(cost_per_byte_ms);
} else {
_cost_per_byte_ms_seq->add(cost_per_byte_ms);
}
}
! void G1Analytics::report_young_other_cost_per_region_ms(double other_cost_per_region_ms) {
! _young_other_cost_per_region_ms_seq->add(other_cost_per_region_ms);
}
! void G1Analytics::report_non_young_other_cost_per_region_ms(double other_cost_per_region_ms) {
! _non_young_other_cost_per_region_ms_seq->add(other_cost_per_region_ms);
}
! void G1Analytics::report_constant_other_time_ms(double constant_other_time_ms) {
! _constant_other_time_ms_seq->add(constant_other_time_ms);
}
! void G1Analytics::report_pending_cards(double pending_cards) {
! _pending_cards_seq->add(pending_cards);
}
! void G1Analytics::report_rs_lengths(double rs_lengths) {
! _rs_lengths_seq->add(rs_lengths);
}
! size_t G1Analytics::predict_rs_length_diff() const {
return get_new_size_prediction(_rs_length_diff_seq);
}
! double G1Analytics::predict_alloc_rate_ms() const {
return get_new_prediction(_alloc_rate_ms_seq);
}
! double G1Analytics::predict_cost_per_card_ms() const {
return get_new_prediction(_cost_per_card_ms_seq);
}
! double G1Analytics::predict_scan_hcc_ms() const {
return get_new_prediction(_cost_scan_hcc_seq);
}
! double G1Analytics::predict_rs_update_time_ms(size_t pending_cards) const {
return pending_cards * predict_cost_per_card_ms() + predict_scan_hcc_ms();
}
! double G1Analytics::predict_young_cards_per_entry_ratio() const {
return get_new_prediction(_young_cards_per_entry_ratio_seq);
}
! double G1Analytics::predict_mixed_cards_per_entry_ratio() const {
if (_mixed_cards_per_entry_ratio_seq->num() < 2) {
return predict_young_cards_per_entry_ratio();
} else {
return get_new_prediction(_mixed_cards_per_entry_ratio_seq);
}
}
! size_t G1Analytics::predict_card_num(size_t rs_length, bool gcs_are_young) const {
! if (gcs_are_young) {
return (size_t) (rs_length * predict_young_cards_per_entry_ratio());
+ } else {
+ return (size_t) (rs_length * predict_mixed_cards_per_entry_ratio());
+ }
}
! double G1Analytics::predict_rs_scan_time_ms(size_t card_num, bool gcs_are_young) const {
! if (gcs_are_young) {
return card_num * get_new_prediction(_cost_per_entry_ms_seq);
} else {
return predict_mixed_rs_scan_time_ms(card_num);
}
}
! double G1Analytics::predict_mixed_rs_scan_time_ms(size_t card_num) const {
if (_mixed_cost_per_entry_ms_seq->num() < 3) {
return card_num * get_new_prediction(_cost_per_entry_ms_seq);
} else {
return card_num * get_new_prediction(_mixed_cost_per_entry_ms_seq);
}
}
! double G1Analytics::predict_object_copy_time_ms_during_cm(size_t bytes_to_copy) const {
if (_cost_per_byte_ms_during_cm_seq->num() < 3) {
return (1.1 * bytes_to_copy) * get_new_prediction(_cost_per_byte_ms_seq);
} else {
return bytes_to_copy * get_new_prediction(_cost_per_byte_ms_during_cm_seq);
}
}
! double G1Analytics::predict_object_copy_time_ms(size_t bytes_to_copy, bool during_concurrent_mark) const {
! if (during_concurrent_mark) {
return predict_object_copy_time_ms_during_cm(bytes_to_copy);
} else {
return bytes_to_copy * get_new_prediction(_cost_per_byte_ms_seq);
}
}
! double G1Analytics::predict_constant_other_time_ms() const {
return get_new_prediction(_constant_other_time_ms_seq);
}
! double G1Analytics::predict_young_other_time_ms(size_t young_num) const {
return young_num * get_new_prediction(_young_other_cost_per_region_ms_seq);
}
! double G1Analytics::predict_non_young_other_time_ms(size_t non_young_num) const {
return non_young_num * get_new_prediction(_non_young_other_cost_per_region_ms_seq);
}
! double G1Analytics::predict_remark_time_ms() const {
return get_new_prediction(_concurrent_mark_remark_times_ms);
}
! double G1Analytics::predict_cleanup_time_ms() const {
return get_new_prediction(_concurrent_mark_cleanup_times_ms);
}
! size_t G1Analytics::predict_rs_lengths() const {
! return get_new_size_prediction(_rs_lengths_seq);
}
! size_t G1Analytics::predict_pending_cards() const {
! return get_new_size_prediction(_pending_cards_seq);
}
! double G1Analytics::last_known_gc_end_time_sec() const {
! return _recent_prev_end_times_for_all_gcs_sec->oldest();
}
! void G1Analytics::update_recent_gc_times(double end_time_sec,
! double pause_time_ms) {
! _recent_gc_times_ms->add(pause_time_ms);
_recent_prev_end_times_for_all_gcs_sec->add(end_time_sec);
_prev_collection_pause_end_ms = end_time_sec * 1000.0;
}
! void G1Analytics::report_concurrent_mark_cleanup_times_ms(double ms) {
! _concurrent_mark_cleanup_times_ms->add(ms);
}
< prev index next >