mirror of
https://github.com/openjdk/jdk.git
synced 2025-08-26 14:24:46 +02:00
2242 lines
87 KiB
C++
2242 lines
87 KiB
C++
/*
|
|
* Copyright (c) 2001, 2013, 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.
|
|
*
|
|
* This code is distributed in the hope that it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
* version 2 for more details (a copy is included in the LICENSE file that
|
|
* accompanied this code).
|
|
*
|
|
* You should have received a copy of the GNU General Public License version
|
|
* 2 along with this work; if not, write to the Free Software Foundation,
|
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*
|
|
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
|
|
* or visit www.oracle.com if you need additional information or have any
|
|
* questions.
|
|
*
|
|
*/
|
|
|
|
#include "precompiled.hpp"
|
|
#include "gc_implementation/g1/concurrentG1Refine.hpp"
|
|
#include "gc_implementation/g1/concurrentMark.hpp"
|
|
#include "gc_implementation/g1/concurrentMarkThread.inline.hpp"
|
|
#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
|
|
#include "gc_implementation/g1/g1CollectorPolicy.hpp"
|
|
#include "gc_implementation/g1/g1ErgoVerbose.hpp"
|
|
#include "gc_implementation/g1/g1GCPhaseTimes.hpp"
|
|
#include "gc_implementation/g1/g1Log.hpp"
|
|
#include "gc_implementation/g1/heapRegionRemSet.hpp"
|
|
#include "gc_implementation/shared/gcPolicyCounters.hpp"
|
|
#include "runtime/arguments.hpp"
|
|
#include "runtime/java.hpp"
|
|
#include "runtime/mutexLocker.hpp"
|
|
#include "utilities/debug.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
|
|
|
|
// all the same
|
|
static double rs_length_diff_defaults[] = {
|
|
0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0
|
|
};
|
|
|
|
static double cost_per_card_ms_defaults[] = {
|
|
0.01, 0.005, 0.005, 0.003, 0.003, 0.002, 0.002, 0.0015
|
|
};
|
|
|
|
// all the same
|
|
static double young_cards_per_entry_ratio_defaults[] = {
|
|
1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0
|
|
};
|
|
|
|
static double cost_per_entry_ms_defaults[] = {
|
|
0.015, 0.01, 0.01, 0.008, 0.008, 0.0055, 0.0055, 0.005
|
|
};
|
|
|
|
static double cost_per_byte_ms_defaults[] = {
|
|
0.00006, 0.00003, 0.00003, 0.000015, 0.000015, 0.00001, 0.00001, 0.000009
|
|
};
|
|
|
|
// these should be pretty consistent
|
|
static double constant_other_time_ms_defaults[] = {
|
|
5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0, 5.0
|
|
};
|
|
|
|
|
|
static double young_other_cost_per_region_ms_defaults[] = {
|
|
0.3, 0.2, 0.2, 0.15, 0.15, 0.12, 0.12, 0.1
|
|
};
|
|
|
|
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() :
|
|
_parallel_gc_threads(G1CollectedHeap::use_parallel_gc_threads()
|
|
? ParallelGCThreads : 1),
|
|
|
|
_recent_gc_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
|
|
_stop_world_start(0.0),
|
|
|
|
_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)),
|
|
_young_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)),
|
|
_mixed_cards_per_entry_ratio_seq(new TruncatedSeq(TruncatedSeqLength)),
|
|
_cost_per_entry_ms_seq(new TruncatedSeq(TruncatedSeqLength)),
|
|
_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),
|
|
|
|
_gcs_are_young(true),
|
|
|
|
_during_marking(false),
|
|
_in_marking_window(false),
|
|
_in_marking_window_im(false),
|
|
|
|
_recent_prev_end_times_for_all_gcs_sec(
|
|
new TruncatedSeq(NumPrevPausesForHeuristics)),
|
|
|
|
_recent_avg_pause_time_ratio(0.0),
|
|
|
|
_initiate_conc_mark_if_possible(false),
|
|
_during_initial_mark_pause(false),
|
|
_last_young_gc(false),
|
|
_last_gc_was_young(false),
|
|
|
|
_eden_used_bytes_before_gc(0),
|
|
_survivor_used_bytes_before_gc(0),
|
|
_heap_used_bytes_before_gc(0),
|
|
_metaspace_used_bytes_before_gc(0),
|
|
_eden_capacity_bytes_before_gc(0),
|
|
_heap_capacity_bytes_before_gc(0),
|
|
|
|
_eden_cset_region_length(0),
|
|
_survivor_cset_region_length(0),
|
|
_old_cset_region_length(0),
|
|
|
|
_collection_set(NULL),
|
|
_collection_set_bytes_used_before(0),
|
|
|
|
// Incremental CSet attributes
|
|
_inc_cset_build_state(Inactive),
|
|
_inc_cset_head(NULL),
|
|
_inc_cset_tail(NULL),
|
|
_inc_cset_bytes_used_before(0),
|
|
_inc_cset_max_finger(NULL),
|
|
_inc_cset_recorded_rs_lengths(0),
|
|
_inc_cset_recorded_rs_lengths_diffs(0),
|
|
_inc_cset_predicted_elapsed_time_ms(0.0),
|
|
_inc_cset_predicted_elapsed_time_ms_diffs(0.0),
|
|
|
|
#ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
|
|
#pragma warning( disable:4355 ) // 'this' : used in base member initializer list
|
|
#endif // _MSC_VER
|
|
|
|
_short_lived_surv_rate_group(new SurvRateGroup(this, "Short Lived",
|
|
G1YoungSurvRateNumRegionsSummary)),
|
|
_survivor_surv_rate_group(new SurvRateGroup(this, "Survivor",
|
|
G1YoungSurvRateNumRegionsSummary)),
|
|
// add here any more surv rate groups
|
|
_recorded_survivor_regions(0),
|
|
_recorded_survivor_head(NULL),
|
|
_recorded_survivor_tail(NULL),
|
|
_survivors_age_table(true),
|
|
|
|
_gc_overhead_perc(0.0) {
|
|
|
|
// 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();
|
|
|
|
G1ErgoVerbose::initialize();
|
|
if (PrintAdaptiveSizePolicy) {
|
|
// Currently, we only use a single switch for all the heuristics.
|
|
G1ErgoVerbose::set_enabled(true);
|
|
// Given that we don't currently have a verboseness level
|
|
// parameter, we'll hardcode this to high. This can be easily
|
|
// changed in the future.
|
|
G1ErgoVerbose::set_level(ErgoHigh);
|
|
} else {
|
|
G1ErgoVerbose::set_enabled(false);
|
|
}
|
|
|
|
// Verify PLAB sizes
|
|
const size_t region_size = HeapRegion::GrainWords;
|
|
if (YoungPLABSize > region_size || OldPLABSize > region_size) {
|
|
char buffer[128];
|
|
jio_snprintf(buffer, sizeof(buffer), "%sPLABSize should be at most "SIZE_FORMAT,
|
|
OldPLABSize > region_size ? "Old" : "Young", region_size);
|
|
vm_exit_during_initialization(buffer);
|
|
}
|
|
|
|
_recent_prev_end_times_for_all_gcs_sec->add(os::elapsedTime());
|
|
_prev_collection_pause_end_ms = os::elapsedTime() * 1000.0;
|
|
|
|
_phase_times = new G1GCPhaseTimes(_parallel_gc_threads);
|
|
|
|
int index = MIN2(_parallel_gc_threads - 1, 7);
|
|
|
|
_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(
|
|
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);
|
|
|
|
uintx confidence_perc = G1ConfidencePercent;
|
|
// Put an artificial ceiling on this so that it's not set to a silly value.
|
|
if (confidence_perc > 100) {
|
|
confidence_perc = 100;
|
|
warning("G1ConfidencePercent is set to a value that is too large, "
|
|
"it's been updated to %u", confidence_perc);
|
|
}
|
|
_sigma = (double) confidence_perc / 100.0;
|
|
|
|
// 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;
|
|
// _max_survivor_regions will be calculated by
|
|
// update_young_list_target_length() during initialization.
|
|
_max_survivor_regions = 0;
|
|
|
|
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 %u", 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;
|
|
|
|
initialize_all();
|
|
_collectionSetChooser = new CollectionSetChooser();
|
|
_young_gen_sizer = new G1YoungGenSizer(); // Must be after call to initialize_flags
|
|
}
|
|
|
|
void G1CollectorPolicy::initialize_flags() {
|
|
set_min_alignment(HeapRegion::GrainBytes);
|
|
size_t card_table_alignment = GenRemSet::max_alignment_constraint(rem_set_name());
|
|
size_t page_size = UseLargePages ? os::large_page_size() : os::vm_page_size();
|
|
set_max_alignment(MAX3(card_table_alignment, min_alignment(), page_size));
|
|
if (SurvivorRatio < 1) {
|
|
vm_exit_during_initialization("Invalid survivor ratio specified");
|
|
}
|
|
CollectorPolicy::initialize_flags();
|
|
}
|
|
|
|
G1YoungGenSizer::G1YoungGenSizer() : _sizer_kind(SizerDefaults), _adaptive_size(true) {
|
|
assert(G1NewSizePercent <= G1MaxNewSizePercent, "Min larger than max");
|
|
assert(G1NewSizePercent > 0 && G1NewSizePercent < 100, "Min out of bounds");
|
|
assert(G1MaxNewSizePercent > 0 && G1MaxNewSizePercent < 100, "Max out of bounds");
|
|
|
|
if (FLAG_IS_CMDLINE(NewRatio)) {
|
|
if (FLAG_IS_CMDLINE(NewSize) || FLAG_IS_CMDLINE(MaxNewSize)) {
|
|
warning("-XX:NewSize and -XX:MaxNewSize override -XX:NewRatio");
|
|
} else {
|
|
_sizer_kind = SizerNewRatio;
|
|
_adaptive_size = false;
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (FLAG_IS_CMDLINE(NewSize)) {
|
|
_min_desired_young_length = MAX2((uint) (NewSize / HeapRegion::GrainBytes),
|
|
1U);
|
|
if (FLAG_IS_CMDLINE(MaxNewSize)) {
|
|
_max_desired_young_length =
|
|
MAX2((uint) (MaxNewSize / HeapRegion::GrainBytes),
|
|
1U);
|
|
_sizer_kind = SizerMaxAndNewSize;
|
|
_adaptive_size = _min_desired_young_length == _max_desired_young_length;
|
|
} else {
|
|
_sizer_kind = SizerNewSizeOnly;
|
|
}
|
|
} else if (FLAG_IS_CMDLINE(MaxNewSize)) {
|
|
_max_desired_young_length =
|
|
MAX2((uint) (MaxNewSize / HeapRegion::GrainBytes),
|
|
1U);
|
|
_sizer_kind = SizerMaxNewSizeOnly;
|
|
}
|
|
}
|
|
|
|
uint G1YoungGenSizer::calculate_default_min_length(uint new_number_of_heap_regions) {
|
|
uint default_value = (new_number_of_heap_regions * G1NewSizePercent) / 100;
|
|
return MAX2(1U, default_value);
|
|
}
|
|
|
|
uint G1YoungGenSizer::calculate_default_max_length(uint new_number_of_heap_regions) {
|
|
uint default_value = (new_number_of_heap_regions * G1MaxNewSizePercent) / 100;
|
|
return MAX2(1U, default_value);
|
|
}
|
|
|
|
void G1YoungGenSizer::heap_size_changed(uint new_number_of_heap_regions) {
|
|
assert(new_number_of_heap_regions > 0, "Heap must be initialized");
|
|
|
|
switch (_sizer_kind) {
|
|
case SizerDefaults:
|
|
_min_desired_young_length = calculate_default_min_length(new_number_of_heap_regions);
|
|
_max_desired_young_length = calculate_default_max_length(new_number_of_heap_regions);
|
|
break;
|
|
case SizerNewSizeOnly:
|
|
_max_desired_young_length = calculate_default_max_length(new_number_of_heap_regions);
|
|
_max_desired_young_length = MAX2(_min_desired_young_length, _max_desired_young_length);
|
|
break;
|
|
case SizerMaxNewSizeOnly:
|
|
_min_desired_young_length = calculate_default_min_length(new_number_of_heap_regions);
|
|
_min_desired_young_length = MIN2(_min_desired_young_length, _max_desired_young_length);
|
|
break;
|
|
case SizerMaxAndNewSize:
|
|
// Do nothing. Values set on the command line, don't update them at runtime.
|
|
break;
|
|
case SizerNewRatio:
|
|
_min_desired_young_length = new_number_of_heap_regions / (NewRatio + 1);
|
|
_max_desired_young_length = _min_desired_young_length;
|
|
break;
|
|
default:
|
|
ShouldNotReachHere();
|
|
}
|
|
|
|
assert(_min_desired_young_length <= _max_desired_young_length, "Invalid min/max young gen size values");
|
|
}
|
|
|
|
void G1CollectorPolicy::init() {
|
|
// Set aside an initial future to_space.
|
|
_g1 = G1CollectedHeap::heap();
|
|
|
|
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->free_regions();
|
|
update_young_list_target_length();
|
|
|
|
// We may immediately start allocating regions and placing them on the
|
|
// collection set list. Initialize the per-collection set info
|
|
start_incremental_cset_building();
|
|
}
|
|
|
|
// 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) {
|
|
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;
|
|
if ((2.0 * sigma()) * (double) bytes_to_copy > (double) free_bytes) {
|
|
// end condition 3: out-of-space (conservatively!)
|
|
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);
|
|
}
|
|
|
|
uint G1CollectorPolicy::calculate_young_list_desired_min_length(
|
|
uint base_min_length) {
|
|
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() {
|
|
// 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();
|
|
}
|
|
|
|
void G1CollectorPolicy::update_young_list_target_length(size_t rs_lengths) {
|
|
if (rs_lengths == (size_t) -1) {
|
|
// if it's set to the default value (-1), we should predict it;
|
|
// otherwise, use the given value.
|
|
rs_lengths = (size_t) get_new_prediction(_rs_lengths_seq);
|
|
}
|
|
|
|
// Calculate the absolute and desired min bounds.
|
|
|
|
// This is how many young regions we already have (currently: the survivors).
|
|
uint base_min_length = recorded_survivor_regions();
|
|
// This is the absolute minimum young length, which ensures that we
|
|
// can allocate one eden region in the worst-case.
|
|
uint absolute_min_length = base_min_length + 1;
|
|
uint desired_min_length =
|
|
calculate_young_list_desired_min_length(base_min_length);
|
|
if (desired_min_length < absolute_min_length) {
|
|
desired_min_length = absolute_min_length;
|
|
}
|
|
|
|
// Calculate the absolute and desired max bounds.
|
|
|
|
// 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;
|
|
}
|
|
uint desired_max_length = calculate_young_list_desired_max_length();
|
|
if (desired_max_length > absolute_max_length) {
|
|
desired_max_length = absolute_max_length;
|
|
}
|
|
|
|
uint young_list_target_length = 0;
|
|
if (adaptive_young_list_length()) {
|
|
if (gcs_are_young()) {
|
|
young_list_target_length =
|
|
calculate_young_list_target_length(rs_lengths,
|
|
base_min_length,
|
|
desired_min_length,
|
|
desired_max_length);
|
|
_rs_lengths_prediction = rs_lengths;
|
|
} 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;
|
|
}
|
|
|
|
// 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 > recorded_survivor_regions(),
|
|
"we should be able to allocate at least one eden region");
|
|
assert(young_list_target_length >= absolute_min_length, "post-condition");
|
|
_young_list_target_length = young_list_target_length;
|
|
|
|
update_max_gc_locker_expansion();
|
|
}
|
|
|
|
uint
|
|
G1CollectorPolicy::calculate_young_list_target_length(size_t rs_lengths,
|
|
uint base_min_length,
|
|
uint desired_min_length,
|
|
uint desired_max_length) {
|
|
assert(adaptive_young_list_length(), "pre-condition");
|
|
assert(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 = (size_t) get_new_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() {
|
|
double survivor_regions_evac_time = 0.0;
|
|
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, gcs_are_young());
|
|
}
|
|
return survivor_regions_evac_time;
|
|
}
|
|
|
|
void G1CollectorPolicy::revise_young_list_target_length_if_necessary() {
|
|
guarantee( adaptive_young_list_length(), "should not call this otherwise" );
|
|
|
|
size_t rs_lengths = _g1->young_list()->sampled_rs_lengths();
|
|
if (rs_lengths > _rs_lengths_prediction) {
|
|
// add 10% to avoid having to recalculate often
|
|
size_t rs_lengths_prediction = rs_lengths * 1100 / 1000;
|
|
update_young_list_target_length(rs_lengths_prediction);
|
|
}
|
|
}
|
|
|
|
|
|
|
|
HeapWord* G1CollectorPolicy::mem_allocate_work(size_t size,
|
|
bool is_tlab,
|
|
bool* gc_overhead_limit_was_exceeded) {
|
|
guarantee(false, "Not using this policy feature yet.");
|
|
return NULL;
|
|
}
|
|
|
|
// This method controls how a collector handles one or more
|
|
// of its generations being fully allocated.
|
|
HeapWord* G1CollectorPolicy::satisfy_failed_allocation(size_t size,
|
|
bool is_tlab) {
|
|
guarantee(false, "Not using this policy feature yet.");
|
|
return NULL;
|
|
}
|
|
|
|
|
|
#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()) {
|
|
gclog_or_tty->print_cr("## %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) {
|
|
gclog_or_tty->print_cr("## %s: encountered negative age", name);
|
|
ret = false;
|
|
}
|
|
|
|
if (age <= prev_age) {
|
|
gclog_or_tty->print_cr("## %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();
|
|
record_heap_size_info_at_start(true /* full */);
|
|
// Release the future to-space so that it is available for compaction into.
|
|
_g1->set_full_collection();
|
|
}
|
|
|
|
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;
|
|
|
|
_trace_gen1_time_data.record_full_collection(full_gc_time_ms);
|
|
|
|
update_recent_gc_times(end_sec, full_gc_time_ms);
|
|
|
|
_g1->clear_full_collection();
|
|
|
|
// "Nuke" the heuristics that control the young/mixed GC
|
|
// transitions and make sure we start with young GCs after the Full GC.
|
|
set_gcs_are_young(true);
|
|
_last_young_gc = false;
|
|
clear_initiate_conc_mark_if_possible();
|
|
clear_during_initial_mark_pause();
|
|
_in_marking_window = false;
|
|
_in_marking_window_im = false;
|
|
|
|
_short_lived_surv_rate_group->start_adding_regions();
|
|
// also call this on any additional surv rate groups
|
|
|
|
record_survivor_regions(0, NULL, NULL);
|
|
|
|
_free_regions_at_end_of_collection = _g1->free_regions();
|
|
// Reset survivors SurvRateGroup.
|
|
_survivor_surv_rate_group->reset();
|
|
update_young_list_target_length();
|
|
_collectionSetChooser->clear();
|
|
}
|
|
|
|
void G1CollectorPolicy::record_stop_world_start() {
|
|
_stop_world_start = os::elapsedTime();
|
|
}
|
|
|
|
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(),
|
|
err_msg("sanity, used: "SIZE_FORMAT" recalculate_used: "SIZE_FORMAT,
|
|
_g1->used(), _g1->recalculate_used()));
|
|
|
|
double s_w_t_ms = (start_time_sec - _stop_world_start) * 1000.0;
|
|
_trace_gen0_time_data.record_start_collection(s_w_t_ms);
|
|
_stop_world_start = 0.0;
|
|
|
|
record_heap_size_info_at_start(false /* full */);
|
|
|
|
phase_times()->record_cur_collection_start_sec(start_time_sec);
|
|
_pending_cards = _g1->pending_card_num();
|
|
|
|
_collection_set_bytes_used_before = 0;
|
|
_bytes_copied_during_gc = 0;
|
|
|
|
_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) {
|
|
_during_marking = true;
|
|
assert(!initiate_conc_mark_if_possible(), "we should have cleared it by now");
|
|
clear_during_initial_mark_pause();
|
|
_cur_mark_stop_world_time_ms = mark_init_elapsed_time_ms;
|
|
}
|
|
|
|
void G1CollectorPolicy::record_concurrent_mark_remark_start() {
|
|
_mark_remark_start_sec = os::elapsedTime();
|
|
_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);
|
|
_cur_mark_stop_world_time_ms += elapsed_time_ms;
|
|
_prev_collection_pause_end_ms += elapsed_time_ms;
|
|
|
|
_mmu_tracker->add_pause(_mark_remark_start_sec, end_time_sec, true);
|
|
}
|
|
|
|
void G1CollectorPolicy::record_concurrent_mark_cleanup_start() {
|
|
_mark_cleanup_start_sec = os::elapsedTime();
|
|
}
|
|
|
|
void G1CollectorPolicy::record_concurrent_mark_cleanup_completed() {
|
|
_last_young_gc = true;
|
|
_in_marking_window = false;
|
|
}
|
|
|
|
void G1CollectorPolicy::record_concurrent_pause() {
|
|
if (_stop_world_start > 0.0) {
|
|
double yield_ms = (os::elapsedTime() - _stop_world_start) * 1000.0;
|
|
_trace_gen0_time_data.record_yield_time(yield_ms);
|
|
}
|
|
}
|
|
|
|
bool G1CollectorPolicy::need_to_start_conc_mark(const char* source, size_t alloc_word_size) {
|
|
if (_g1->concurrent_mark()->cmThread()->during_cycle()) {
|
|
return false;
|
|
}
|
|
|
|
size_t marking_initiating_used_threshold =
|
|
(_g1->capacity() / 100) * InitiatingHeapOccupancyPercent;
|
|
size_t cur_used_bytes = _g1->non_young_capacity_bytes();
|
|
size_t alloc_byte_size = alloc_word_size * HeapWordSize;
|
|
|
|
if ((cur_used_bytes + alloc_byte_size) > marking_initiating_used_threshold) {
|
|
if (gcs_are_young() && !_last_young_gc) {
|
|
ergo_verbose5(ErgoConcCycles,
|
|
"request concurrent cycle initiation",
|
|
ergo_format_reason("occupancy higher than threshold")
|
|
ergo_format_byte("occupancy")
|
|
ergo_format_byte("allocation request")
|
|
ergo_format_byte_perc("threshold")
|
|
ergo_format_str("source"),
|
|
cur_used_bytes,
|
|
alloc_byte_size,
|
|
marking_initiating_used_threshold,
|
|
(double) InitiatingHeapOccupancyPercent,
|
|
source);
|
|
return true;
|
|
} else {
|
|
ergo_verbose5(ErgoConcCycles,
|
|
"do not request concurrent cycle initiation",
|
|
ergo_format_reason("still doing mixed collections")
|
|
ergo_format_byte("occupancy")
|
|
ergo_format_byte("allocation request")
|
|
ergo_format_byte_perc("threshold")
|
|
ergo_format_str("source"),
|
|
cur_used_bytes,
|
|
alloc_byte_size,
|
|
marking_initiating_used_threshold,
|
|
(double) InitiatingHeapOccupancyPercent,
|
|
source);
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
// Anything below that is considered to be zero
|
|
#define MIN_TIMER_GRANULARITY 0.0000001
|
|
|
|
void G1CollectorPolicy::record_collection_pause_end(double pause_time_ms, EvacuationInfo& evacuation_info) {
|
|
double end_time_sec = os::elapsedTime();
|
|
assert(_cur_collection_pause_used_regions_at_start >= cset_region_length(),
|
|
"otherwise, the subtraction below does not make sense");
|
|
size_t rs_size =
|
|
_cur_collection_pause_used_regions_at_start - cset_region_length();
|
|
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();
|
|
|
|
#ifndef PRODUCT
|
|
if (G1YoungSurvRateVerbose) {
|
|
gclog_or_tty->print_cr("");
|
|
_short_lived_surv_rate_group->print();
|
|
// do that for any other surv rate groups too
|
|
}
|
|
#endif // PRODUCT
|
|
|
|
last_pause_included_initial_mark = during_initial_mark_pause();
|
|
if (last_pause_included_initial_mark) {
|
|
record_concurrent_mark_init_end(0.0);
|
|
} else 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.
|
|
set_initiate_conc_mark_if_possible();
|
|
}
|
|
|
|
_mmu_tracker->add_pause(end_time_sec - pause_time_ms/1000.0,
|
|
end_time_sec, false);
|
|
|
|
evacuation_info.set_collectionset_used_before(_collection_set_bytes_used_before);
|
|
evacuation_info.set_bytes_copied(_bytes_copied_during_gc);
|
|
|
|
if (update_stats) {
|
|
_trace_gen0_time_data.record_end_collection(pause_time_ms, phase_times());
|
|
// this is where we update the allocation rate of the application
|
|
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;
|
|
}
|
|
// 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 = eden_cset_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)) {
|
|
#ifndef PRODUCT
|
|
// Dump info to allow post-facto debugging
|
|
gclog_or_tty->print_cr("recent_avg_pause_time_ratio() out of bounds");
|
|
gclog_or_tty->print_cr("-------------------------------------------");
|
|
gclog_or_tty->print_cr("Recent GC Times (ms):");
|
|
_recent_gc_times_ms->dump();
|
|
gclog_or_tty->print_cr("(End Time=%3.3f) Recent GC End Times (s):", end_time_sec);
|
|
_recent_prev_end_times_for_all_gcs_sec->dump();
|
|
gclog_or_tty->print_cr("GC = %3.3f, Interval = %3.3f, Ratio = %3.3f",
|
|
_recent_gc_times_ms->sum(), interval_ms, recent_avg_pause_time_ratio());
|
|
// In debug mode, terminate the JVM if the user wants to debug at this point.
|
|
assert(!G1FailOnFPError, "Debugging data for CR 6898948 has been dumped above");
|
|
#endif // !PRODUCT
|
|
// 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 {
|
|
assert(_recent_avg_pause_time_ratio - 1.0 > 0.0, "Ctl-point invariant");
|
|
_recent_avg_pause_time_ratio = 1.0;
|
|
}
|
|
}
|
|
}
|
|
|
|
bool new_in_marking_window = _in_marking_window;
|
|
bool new_in_marking_window_im = false;
|
|
if (during_initial_mark_pause()) {
|
|
new_in_marking_window = true;
|
|
new_in_marking_window_im = true;
|
|
}
|
|
|
|
if (_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.
|
|
|
|
if (!last_pause_included_initial_mark) {
|
|
if (next_gc_should_be_mixed("start mixed GCs",
|
|
"do not start mixed GCs")) {
|
|
set_gcs_are_young(false);
|
|
}
|
|
} else {
|
|
ergo_verbose0(ErgoMixedGCs,
|
|
"do not start mixed GCs",
|
|
ergo_format_reason("concurrent cycle is about to start"));
|
|
}
|
|
_last_young_gc = false;
|
|
}
|
|
|
|
if (!_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")) {
|
|
set_gcs_are_young(true);
|
|
}
|
|
}
|
|
|
|
_short_lived_surv_rate_group->start_adding_regions();
|
|
// do that for any other surv rate groupsx
|
|
|
|
if (update_stats) {
|
|
double cost_per_card_ms = 0.0;
|
|
if (_pending_cards > 0) {
|
|
cost_per_card_ms = phase_times()->average_last_update_rs_time() / (double) _pending_cards;
|
|
_cost_per_card_ms_seq->add(cost_per_card_ms);
|
|
}
|
|
|
|
size_t cards_scanned = _g1->cards_scanned();
|
|
|
|
double cost_per_entry_ms = 0.0;
|
|
if (cards_scanned > 10) {
|
|
cost_per_entry_ms = phase_times()->average_last_scan_rs_time() / (double) cards_scanned;
|
|
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);
|
|
}
|
|
}
|
|
|
|
if (_max_rs_lengths > 0) {
|
|
double cards_per_entry_ratio =
|
|
(double) cards_scanned / (double) _max_rs_lengths;
|
|
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);
|
|
}
|
|
}
|
|
|
|
// 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;
|
|
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 = phase_times()->average_last_obj_copy_time() / (double) copied_bytes;
|
|
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);
|
|
}
|
|
}
|
|
|
|
double all_other_time_ms = pause_time_ms -
|
|
(phase_times()->average_last_update_rs_time() + phase_times()->average_last_scan_rs_time()
|
|
+ phase_times()->average_last_obj_copy_time() + phase_times()->average_last_termination_time());
|
|
|
|
double young_other_time_ms = 0.0;
|
|
if (young_cset_region_length() > 0) {
|
|
young_other_time_ms =
|
|
phase_times()->young_cset_choice_time_ms() +
|
|
phase_times()->young_free_cset_time_ms();
|
|
_young_other_cost_per_region_ms_seq->add(young_other_time_ms /
|
|
(double) young_cset_region_length());
|
|
}
|
|
double non_young_other_time_ms = 0.0;
|
|
if (old_cset_region_length() > 0) {
|
|
non_young_other_time_ms =
|
|
phase_times()->non_young_cset_choice_time_ms() +
|
|
phase_times()->non_young_free_cset_time_ms();
|
|
|
|
_non_young_other_cost_per_region_ms_seq->add(non_young_other_time_ms /
|
|
(double) old_cset_region_length());
|
|
}
|
|
|
|
double constant_other_time_ms = all_other_time_ms -
|
|
(young_other_time_ms + non_young_other_time_ms);
|
|
_constant_other_time_ms_seq->add(constant_other_time_ms);
|
|
|
|
double survival_ratio = 0.0;
|
|
if (_collection_set_bytes_used_before > 0) {
|
|
survival_ratio = (double) _bytes_copied_during_gc /
|
|
(double) _collection_set_bytes_used_before;
|
|
}
|
|
|
|
_pending_cards_seq->add((double) _pending_cards);
|
|
_rs_lengths_seq->add((double) _max_rs_lengths);
|
|
}
|
|
|
|
_in_marking_window = new_in_marking_window;
|
|
_in_marking_window_im = new_in_marking_window_im;
|
|
_free_regions_at_end_of_collection = _g1->free_regions();
|
|
update_young_list_target_length();
|
|
|
|
// 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;
|
|
adjust_concurrent_refinement(phase_times()->average_last_update_rs_time(),
|
|
phase_times()->sum_last_update_rs_processed_buffers(), update_rs_time_goal_ms);
|
|
|
|
_collectionSetChooser->verify();
|
|
}
|
|
|
|
#define EXT_SIZE_FORMAT "%.1f%s"
|
|
#define EXT_SIZE_PARAMS(bytes) \
|
|
byte_size_in_proper_unit((double)(bytes)), \
|
|
proper_unit_for_byte_size((bytes))
|
|
|
|
void G1CollectorPolicy::record_heap_size_info_at_start(bool full) {
|
|
YoungList* young_list = _g1->young_list();
|
|
_eden_used_bytes_before_gc = young_list->eden_used_bytes();
|
|
_survivor_used_bytes_before_gc = young_list->survivor_used_bytes();
|
|
_heap_capacity_bytes_before_gc = _g1->capacity();
|
|
_heap_used_bytes_before_gc = _g1->used();
|
|
_cur_collection_pause_used_regions_at_start = _g1->used_regions();
|
|
|
|
_eden_capacity_bytes_before_gc =
|
|
(_young_list_target_length * HeapRegion::GrainBytes) - _survivor_used_bytes_before_gc;
|
|
|
|
if (full) {
|
|
_metaspace_used_bytes_before_gc = MetaspaceAux::allocated_used_bytes();
|
|
}
|
|
}
|
|
|
|
void G1CollectorPolicy::print_heap_transition() {
|
|
_g1->print_size_transition(gclog_or_tty,
|
|
_heap_used_bytes_before_gc,
|
|
_g1->used(),
|
|
_g1->capacity());
|
|
}
|
|
|
|
void G1CollectorPolicy::print_detailed_heap_transition(bool full) {
|
|
YoungList* young_list = _g1->young_list();
|
|
|
|
size_t eden_used_bytes_after_gc = young_list->eden_used_bytes();
|
|
size_t survivor_used_bytes_after_gc = young_list->survivor_used_bytes();
|
|
size_t heap_used_bytes_after_gc = _g1->used();
|
|
|
|
size_t heap_capacity_bytes_after_gc = _g1->capacity();
|
|
size_t eden_capacity_bytes_after_gc =
|
|
(_young_list_target_length * HeapRegion::GrainBytes) - survivor_used_bytes_after_gc;
|
|
|
|
gclog_or_tty->print(
|
|
" [Eden: "EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")->"EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT") "
|
|
"Survivors: "EXT_SIZE_FORMAT"->"EXT_SIZE_FORMAT" "
|
|
"Heap: "EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")->"
|
|
EXT_SIZE_FORMAT"("EXT_SIZE_FORMAT")]",
|
|
EXT_SIZE_PARAMS(_eden_used_bytes_before_gc),
|
|
EXT_SIZE_PARAMS(_eden_capacity_bytes_before_gc),
|
|
EXT_SIZE_PARAMS(eden_used_bytes_after_gc),
|
|
EXT_SIZE_PARAMS(eden_capacity_bytes_after_gc),
|
|
EXT_SIZE_PARAMS(_survivor_used_bytes_before_gc),
|
|
EXT_SIZE_PARAMS(survivor_used_bytes_after_gc),
|
|
EXT_SIZE_PARAMS(_heap_used_bytes_before_gc),
|
|
EXT_SIZE_PARAMS(_heap_capacity_bytes_before_gc),
|
|
EXT_SIZE_PARAMS(heap_used_bytes_after_gc),
|
|
EXT_SIZE_PARAMS(heap_capacity_bytes_after_gc));
|
|
|
|
if (full) {
|
|
MetaspaceAux::print_metaspace_change(_metaspace_used_bytes_before_gc);
|
|
}
|
|
|
|
gclog_or_tty->cr();
|
|
}
|
|
|
|
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;
|
|
|
|
int g = cg1r->green_zone();
|
|
if (update_rs_time > goal_ms) {
|
|
g = (int)(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 = (int)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();
|
|
|
|
int processing_threshold_delta = MAX2((int)(cg1r->green_zone() * sigma()), 1);
|
|
int processing_threshold = MIN2(cg1r->green_zone() + processing_threshold_delta,
|
|
cg1r->yellow_zone());
|
|
// Change the barrier params
|
|
dcqs.set_process_completed_threshold(processing_threshold);
|
|
dcqs.set_max_completed_queue(cg1r->red_zone());
|
|
}
|
|
|
|
int 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();
|
|
}
|
|
|
|
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();
|
|
size_t card_num;
|
|
if (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) {
|
|
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 for_young_gc) {
|
|
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::init_cset_region_lengths(uint eden_cset_region_length,
|
|
uint survivor_cset_region_length) {
|
|
_eden_cset_region_length = eden_cset_region_length;
|
|
_survivor_cset_region_length = survivor_cset_region_length;
|
|
_old_cset_region_length = 0;
|
|
}
|
|
|
|
void G1CollectorPolicy::set_recorded_rs_lengths(size_t rs_lengths) {
|
|
_recorded_rs_lengths = rs_lengths;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
size_t G1CollectorPolicy::expansion_amount() {
|
|
double recent_gc_overhead = recent_avg_pause_time_ratio() * 100.0;
|
|
double threshold = _gc_overhead_perc;
|
|
if (recent_gc_overhead > threshold) {
|
|
// We will double the existing space, or take
|
|
// G1ExpandByPercentOfAvailable % of the available expansion
|
|
// space, whichever is smaller, bounded below by a minimum
|
|
// expansion (unless that's all that's left.)
|
|
const size_t min_expand_bytes = 1*M;
|
|
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;
|
|
size_t expand_bytes_via_pct =
|
|
uncommitted_bytes * G1ExpandByPercentOfAvailable / 100;
|
|
expand_bytes = MIN2(expand_bytes_via_pct, committed_bytes);
|
|
expand_bytes = MAX2(expand_bytes, min_expand_bytes);
|
|
expand_bytes = MIN2(expand_bytes, uncommitted_bytes);
|
|
|
|
ergo_verbose5(ErgoHeapSizing,
|
|
"attempt heap expansion",
|
|
ergo_format_reason("recent GC overhead higher than "
|
|
"threshold after GC")
|
|
ergo_format_perc("recent GC overhead")
|
|
ergo_format_perc("threshold")
|
|
ergo_format_byte("uncommitted")
|
|
ergo_format_byte_perc("calculated expansion amount"),
|
|
recent_gc_overhead, threshold,
|
|
uncommitted_bytes,
|
|
expand_bytes_via_pct, (double) G1ExpandByPercentOfAvailable);
|
|
|
|
return expand_bytes;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
void G1CollectorPolicy::print_tracing_info() const {
|
|
_trace_gen0_time_data.print();
|
|
_trace_gen1_time_data.print();
|
|
}
|
|
|
|
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
|
|
}
|
|
|
|
uint G1CollectorPolicy::max_regions(int purpose) {
|
|
switch (purpose) {
|
|
case GCAllocForSurvived:
|
|
return _max_survivor_regions;
|
|
case GCAllocForTenured:
|
|
return REGIONS_UNLIMITED;
|
|
default:
|
|
ShouldNotReachHere();
|
|
return REGIONS_UNLIMITED;
|
|
};
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
bool G1CollectorPolicy::force_initial_mark_if_outside_cycle(
|
|
GCCause::Cause gc_cause) {
|
|
bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
|
|
if (!during_cycle) {
|
|
ergo_verbose1(ErgoConcCycles,
|
|
"request concurrent cycle initiation",
|
|
ergo_format_reason("requested by GC cause")
|
|
ergo_format_str("GC cause"),
|
|
GCCause::to_string(gc_cause));
|
|
set_initiate_conc_mark_if_possible();
|
|
return true;
|
|
} else {
|
|
ergo_verbose1(ErgoConcCycles,
|
|
"do not request concurrent cycle initiation",
|
|
ergo_format_reason("concurrent cycle already in progress")
|
|
ergo_format_str("GC cause"),
|
|
GCCause::to_string(gc_cause));
|
|
return false;
|
|
}
|
|
}
|
|
|
|
void
|
|
G1CollectorPolicy::decide_on_conc_mark_initiation() {
|
|
// We are about to decide on whether this pause will be an
|
|
// initial-mark pause.
|
|
|
|
// First, 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(!during_initial_mark_pause(), "pre-condition");
|
|
|
|
if (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.
|
|
|
|
bool during_cycle = _g1->concurrent_mark()->cmThread()->during_cycle();
|
|
if (!during_cycle) {
|
|
// The concurrent marking thread is not "during a cycle", i.e.,
|
|
// it has completed the last one. So we can go ahead and
|
|
// initiate a new cycle.
|
|
|
|
set_during_initial_mark_pause();
|
|
// We do not allow mixed GCs during marking.
|
|
if (!gcs_are_young()) {
|
|
set_gcs_are_young(true);
|
|
ergo_verbose0(ErgoMixedGCs,
|
|
"end mixed GCs",
|
|
ergo_format_reason("concurrent cycle is about to start"));
|
|
}
|
|
|
|
// And we can now clear initiate_conc_mark_if_possible() as
|
|
// we've already acted on it.
|
|
clear_initiate_conc_mark_if_possible();
|
|
|
|
ergo_verbose0(ErgoConcCycles,
|
|
"initiate concurrent cycle",
|
|
ergo_format_reason("concurrent cycle initiation requested"));
|
|
} 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.
|
|
ergo_verbose0(ErgoConcCycles,
|
|
"do not initiate concurrent cycle",
|
|
ergo_format_reason("concurrent cycle already in progress"));
|
|
}
|
|
}
|
|
}
|
|
|
|
class KnownGarbageClosure: public HeapRegionClosure {
|
|
G1CollectedHeap* _g1h;
|
|
CollectionSetChooser* _hrSorted;
|
|
|
|
public:
|
|
KnownGarbageClosure(CollectionSetChooser* hrSorted) :
|
|
_g1h(G1CollectedHeap::heap()), _hrSorted(hrSorted) { }
|
|
|
|
bool doHeapRegion(HeapRegion* r) {
|
|
// We only include humongous regions in collection
|
|
// sets when concurrent mark shows that their contained object is
|
|
// unreachable.
|
|
|
|
// 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 (_hrSorted->should_add(r) && !_g1h->is_old_gc_alloc_region(r)) {
|
|
_hrSorted->add_region(r);
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
};
|
|
|
|
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;
|
|
public:
|
|
ParKnownGarbageTask(CollectionSetChooser* hrSorted, uint chunk_size) :
|
|
AbstractGangTask("ParKnownGarbageTask"),
|
|
_hrSorted(hrSorted), _chunk_size(chunk_size),
|
|
_g1(G1CollectedHeap::heap()) { }
|
|
|
|
void work(uint worker_id) {
|
|
ParKnownGarbageHRClosure parKnownGarbageCl(_hrSorted, _chunk_size);
|
|
|
|
// Back to zero for the claim value.
|
|
_g1->heap_region_par_iterate_chunked(&parKnownGarbageCl, worker_id,
|
|
_g1->workers()->active_workers(),
|
|
HeapRegion::InitialClaimValue);
|
|
}
|
|
};
|
|
|
|
void
|
|
G1CollectorPolicy::record_concurrent_mark_cleanup_end(int no_of_gc_threads) {
|
|
_collectionSetChooser->clear();
|
|
|
|
uint region_num = _g1->n_regions();
|
|
if (G1CollectedHeap::use_parallel_gc_threads()) {
|
|
const uint OverpartitionFactor = 4;
|
|
uint WorkUnit;
|
|
// The use of MinChunkSize = 8 in the original code
|
|
// causes some assertion failures when the total number of
|
|
// region is less than 8. The code here tries to fix that.
|
|
// Should the original code also be fixed?
|
|
if (no_of_gc_threads > 0) {
|
|
const uint MinWorkUnit = MAX2(region_num / no_of_gc_threads, 1U);
|
|
WorkUnit = MAX2(region_num / (no_of_gc_threads * OverpartitionFactor),
|
|
MinWorkUnit);
|
|
} else {
|
|
assert(no_of_gc_threads > 0,
|
|
"The active gc workers should be greater than 0");
|
|
// In a product build do something reasonable to avoid a crash.
|
|
const uint MinWorkUnit = MAX2(region_num / (uint) ParallelGCThreads, 1U);
|
|
WorkUnit =
|
|
MAX2(region_num / (uint) (ParallelGCThreads * OverpartitionFactor),
|
|
MinWorkUnit);
|
|
}
|
|
_collectionSetChooser->prepare_for_par_region_addition(_g1->n_regions(),
|
|
WorkUnit);
|
|
ParKnownGarbageTask parKnownGarbageTask(_collectionSetChooser,
|
|
(int) WorkUnit);
|
|
_g1->workers()->run_task(&parKnownGarbageTask);
|
|
|
|
assert(_g1->check_heap_region_claim_values(HeapRegion::InitialClaimValue),
|
|
"sanity check");
|
|
} else {
|
|
KnownGarbageClosure knownGarbagecl(_collectionSetChooser);
|
|
_g1->heap_region_iterate(&knownGarbagecl);
|
|
}
|
|
|
|
_collectionSetChooser->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);
|
|
_cur_mark_stop_world_time_ms += elapsed_time_ms;
|
|
_prev_collection_pause_end_ms += elapsed_time_ms;
|
|
_mmu_tracker->add_pause(_mark_cleanup_start_sec, end_sec, true);
|
|
}
|
|
|
|
// Add the heap region at the head of the non-incremental collection set
|
|
void G1CollectorPolicy::add_old_region_to_cset(HeapRegion* hr) {
|
|
assert(_inc_cset_build_state == Active, "Precondition");
|
|
assert(!hr->is_young(), "non-incremental add of young region");
|
|
|
|
assert(!hr->in_collection_set(), "should not already be in the CSet");
|
|
hr->set_in_collection_set(true);
|
|
hr->set_next_in_collection_set(_collection_set);
|
|
_collection_set = hr;
|
|
_collection_set_bytes_used_before += hr->used();
|
|
_g1->register_region_with_in_cset_fast_test(hr);
|
|
size_t rs_length = hr->rem_set()->occupied();
|
|
_recorded_rs_lengths += rs_length;
|
|
_old_cset_region_length += 1;
|
|
}
|
|
|
|
// Initialize the per-collection-set information
|
|
void G1CollectorPolicy::start_incremental_cset_building() {
|
|
assert(_inc_cset_build_state == Inactive, "Precondition");
|
|
|
|
_inc_cset_head = NULL;
|
|
_inc_cset_tail = NULL;
|
|
_inc_cset_bytes_used_before = 0;
|
|
|
|
_inc_cset_max_finger = 0;
|
|
_inc_cset_recorded_rs_lengths = 0;
|
|
_inc_cset_recorded_rs_lengths_diffs = 0;
|
|
_inc_cset_predicted_elapsed_time_ms = 0.0;
|
|
_inc_cset_predicted_elapsed_time_ms_diffs = 0.0;
|
|
_inc_cset_build_state = Active;
|
|
}
|
|
|
|
void G1CollectorPolicy::finalize_incremental_cset_building() {
|
|
assert(_inc_cset_build_state == Active, "Precondition");
|
|
assert(SafepointSynchronize::is_at_safepoint(), "should be at a safepoint");
|
|
|
|
// The two "main" fields, _inc_cset_recorded_rs_lengths and
|
|
// _inc_cset_predicted_elapsed_time_ms, are updated by the thread
|
|
// that adds a new region to the CSet. Further updates by the
|
|
// concurrent refinement thread that samples the young RSet lengths
|
|
// are accumulated in the *_diffs fields. Here we add the diffs to
|
|
// the "main" fields.
|
|
|
|
if (_inc_cset_recorded_rs_lengths_diffs >= 0) {
|
|
_inc_cset_recorded_rs_lengths += _inc_cset_recorded_rs_lengths_diffs;
|
|
} else {
|
|
// This is defensive. The diff should in theory be always positive
|
|
// as RSets can only grow between GCs. However, given that we
|
|
// sample their size concurrently with other threads updating them
|
|
// it's possible that we might get the wrong size back, which
|
|
// could make the calculations somewhat inaccurate.
|
|
size_t diffs = (size_t) (-_inc_cset_recorded_rs_lengths_diffs);
|
|
if (_inc_cset_recorded_rs_lengths >= diffs) {
|
|
_inc_cset_recorded_rs_lengths -= diffs;
|
|
} else {
|
|
_inc_cset_recorded_rs_lengths = 0;
|
|
}
|
|
}
|
|
_inc_cset_predicted_elapsed_time_ms +=
|
|
_inc_cset_predicted_elapsed_time_ms_diffs;
|
|
|
|
_inc_cset_recorded_rs_lengths_diffs = 0;
|
|
_inc_cset_predicted_elapsed_time_ms_diffs = 0.0;
|
|
}
|
|
|
|
void G1CollectorPolicy::add_to_incremental_cset_info(HeapRegion* hr, size_t rs_length) {
|
|
// This routine is used when:
|
|
// * adding survivor regions to the incremental cset at the end of an
|
|
// evacuation pause,
|
|
// * adding the current allocation region to the incremental cset
|
|
// when it is retired, and
|
|
// * updating existing policy information for a region in the
|
|
// incremental cset via young list RSet sampling.
|
|
// Therefore this routine may be called at a safepoint by the
|
|
// VM thread, or in-between safepoints by mutator threads (when
|
|
// retiring the current allocation region) or a concurrent
|
|
// refine thread (RSet sampling).
|
|
|
|
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;
|
|
_inc_cset_bytes_used_before += used_bytes;
|
|
|
|
// Cache the values we have added to the aggregated informtion
|
|
// in the heap region in case we have to remove this region from
|
|
// the incremental collection set, or it is updated by the
|
|
// rset sampling code
|
|
hr->set_recorded_rs_length(rs_length);
|
|
hr->set_predicted_elapsed_time_ms(region_elapsed_time_ms);
|
|
}
|
|
|
|
void G1CollectorPolicy::update_incremental_cset_info(HeapRegion* hr,
|
|
size_t new_rs_length) {
|
|
// Update the CSet information that is dependent on the new RS length
|
|
assert(hr->is_young(), "Precondition");
|
|
assert(!SafepointSynchronize::is_at_safepoint(),
|
|
"should not be at a safepoint");
|
|
|
|
// We could have updated _inc_cset_recorded_rs_lengths and
|
|
// _inc_cset_predicted_elapsed_time_ms directly but we'd need to do
|
|
// that atomically, as this code is executed by a concurrent
|
|
// refinement thread, potentially concurrently with a mutator thread
|
|
// allocating a new region and also updating the same fields. To
|
|
// avoid the atomic operations we accumulate these updates on two
|
|
// separate fields (*_diffs) and we'll just add them to the "main"
|
|
// fields at the start of a GC.
|
|
|
|
ssize_t old_rs_length = (ssize_t) hr->recorded_rs_length();
|
|
ssize_t rs_lengths_diff = (ssize_t) new_rs_length - old_rs_length;
|
|
_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, 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;
|
|
|
|
hr->set_recorded_rs_length(new_rs_length);
|
|
hr->set_predicted_elapsed_time_ms(new_region_elapsed_time_ms);
|
|
}
|
|
|
|
void G1CollectorPolicy::add_region_to_incremental_cset_common(HeapRegion* hr) {
|
|
assert(hr->is_young(), "invariant");
|
|
assert(hr->young_index_in_cset() > -1, "should have already been set");
|
|
assert(_inc_cset_build_state == Active, "Precondition");
|
|
|
|
// We need to clear and set the cached recorded/cached collection set
|
|
// information in the heap region here (before the region gets added
|
|
// to the collection set). An individual heap region's cached values
|
|
// are calculated, aggregated with the policy collection set info,
|
|
// and cached in the heap region here (initially) and (subsequently)
|
|
// by the Young List sampling code.
|
|
|
|
size_t rs_length = hr->rem_set()->occupied();
|
|
add_to_incremental_cset_info(hr, rs_length);
|
|
|
|
HeapWord* hr_end = hr->end();
|
|
_inc_cset_max_finger = MAX2(_inc_cset_max_finger, hr_end);
|
|
|
|
assert(!hr->in_collection_set(), "invariant");
|
|
hr->set_in_collection_set(true);
|
|
assert( hr->next_in_collection_set() == NULL, "invariant");
|
|
|
|
_g1->register_region_with_in_cset_fast_test(hr);
|
|
}
|
|
|
|
// Add the region at the RHS of the incremental cset
|
|
void G1CollectorPolicy::add_region_to_incremental_cset_rhs(HeapRegion* hr) {
|
|
// We should only ever be appending survivors at the end of a pause
|
|
assert( hr->is_survivor(), "Logic");
|
|
|
|
// Do the 'common' stuff
|
|
add_region_to_incremental_cset_common(hr);
|
|
|
|
// Now add the region at the right hand side
|
|
if (_inc_cset_tail == NULL) {
|
|
assert(_inc_cset_head == NULL, "invariant");
|
|
_inc_cset_head = hr;
|
|
} else {
|
|
_inc_cset_tail->set_next_in_collection_set(hr);
|
|
}
|
|
_inc_cset_tail = hr;
|
|
}
|
|
|
|
// Add the region to the LHS of the incremental cset
|
|
void G1CollectorPolicy::add_region_to_incremental_cset_lhs(HeapRegion* hr) {
|
|
// Survivors should be added to the RHS at the end of a pause
|
|
assert(!hr->is_survivor(), "Logic");
|
|
|
|
// Do the 'common' stuff
|
|
add_region_to_incremental_cset_common(hr);
|
|
|
|
// Add the region at the left hand side
|
|
hr->set_next_in_collection_set(_inc_cset_head);
|
|
if (_inc_cset_head == NULL) {
|
|
assert(_inc_cset_tail == NULL, "Invariant");
|
|
_inc_cset_tail = hr;
|
|
}
|
|
_inc_cset_head = hr;
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
void G1CollectorPolicy::print_collection_set(HeapRegion* list_head, outputStream* st) {
|
|
assert(list_head == inc_cset_head() || list_head == collection_set(), "must be");
|
|
|
|
st->print_cr("\nCollection_set:");
|
|
HeapRegion* csr = list_head;
|
|
while (csr != NULL) {
|
|
HeapRegion* next = csr->next_in_collection_set();
|
|
assert(csr->in_collection_set(), "bad CS");
|
|
st->print_cr(" "HR_FORMAT", P: "PTR_FORMAT "N: "PTR_FORMAT", age: %4d",
|
|
HR_FORMAT_PARAMS(csr),
|
|
csr->prev_top_at_mark_start(), csr->next_top_at_mark_start(),
|
|
csr->age_in_surv_rate_group_cond());
|
|
csr = next;
|
|
}
|
|
}
|
|
#endif // !PRODUCT
|
|
|
|
double G1CollectorPolicy::reclaimable_bytes_perc(size_t reclaimable_bytes) {
|
|
// 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;
|
|
}
|
|
|
|
bool G1CollectorPolicy::next_gc_should_be_mixed(const char* true_action_str,
|
|
const char* false_action_str) {
|
|
CollectionSetChooser* cset_chooser = _collectionSetChooser;
|
|
if (cset_chooser->is_empty()) {
|
|
ergo_verbose0(ErgoMixedGCs,
|
|
false_action_str,
|
|
ergo_format_reason("candidate old regions not available"));
|
|
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) {
|
|
ergo_verbose4(ErgoMixedGCs,
|
|
false_action_str,
|
|
ergo_format_reason("reclaimable percentage not over threshold")
|
|
ergo_format_region("candidate old regions")
|
|
ergo_format_byte_perc("reclaimable")
|
|
ergo_format_perc("threshold"),
|
|
cset_chooser->remaining_regions(),
|
|
reclaimable_bytes,
|
|
reclaimable_perc, threshold);
|
|
return false;
|
|
}
|
|
|
|
ergo_verbose4(ErgoMixedGCs,
|
|
true_action_str,
|
|
ergo_format_reason("candidate old regions available")
|
|
ergo_format_region("candidate old regions")
|
|
ergo_format_byte_perc("reclaimable")
|
|
ergo_format_perc("threshold"),
|
|
cset_chooser->remaining_regions(),
|
|
reclaimable_bytes,
|
|
reclaimable_perc, threshold);
|
|
return true;
|
|
}
|
|
|
|
uint G1CollectorPolicy::calc_min_old_cset_length() {
|
|
// 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) _collectionSetChooser->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() {
|
|
// 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.
|
|
|
|
G1CollectedHeap* g1h = G1CollectedHeap::heap();
|
|
const size_t region_num = g1h->n_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_cset(double target_pause_time_ms, EvacuationInfo& evacuation_info) {
|
|
double young_start_time_sec = os::elapsedTime();
|
|
|
|
YoungList* young_list = _g1->young_list();
|
|
finalize_incremental_cset_building();
|
|
|
|
guarantee(target_pause_time_ms > 0.0,
|
|
err_msg("target_pause_time_ms = %1.6lf should be positive",
|
|
target_pause_time_ms));
|
|
guarantee(_collection_set == NULL, "Precondition");
|
|
|
|
double base_time_ms = predict_base_elapsed_time_ms(_pending_cards);
|
|
double predicted_pause_time_ms = base_time_ms;
|
|
double time_remaining_ms = MAX2(target_pause_time_ms - base_time_ms, 0.0);
|
|
|
|
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"),
|
|
_pending_cards, base_time_ms, time_remaining_ms, target_pause_time_ms);
|
|
|
|
_last_gc_was_young = gcs_are_young() ? true : false;
|
|
|
|
if (_last_gc_was_young) {
|
|
_trace_gen0_time_data.increment_young_collection_count();
|
|
} else {
|
|
_trace_gen0_time_data.increment_mixed_collection_count();
|
|
}
|
|
|
|
// The young list is laid with the survivor regions from the previous
|
|
// pause are appended to the RHS of the young list, i.e.
|
|
// [Newly Young Regions ++ Survivors from last pause].
|
|
|
|
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);
|
|
|
|
HeapRegion* hr = young_list->first_survivor_region();
|
|
while (hr != NULL) {
|
|
assert(hr->is_survivor(), "badly formed young list");
|
|
hr->set_young();
|
|
hr = hr->get_next_young_region();
|
|
}
|
|
|
|
// Clear the fields that point to the survivor list - they are all young now.
|
|
young_list->clear_survivors();
|
|
|
|
_collection_set = _inc_cset_head;
|
|
_collection_set_bytes_used_before = _inc_cset_bytes_used_before;
|
|
time_remaining_ms = MAX2(time_remaining_ms - _inc_cset_predicted_elapsed_time_ms, 0.0);
|
|
predicted_pause_time_ms += _inc_cset_predicted_elapsed_time_ms;
|
|
|
|
ergo_verbose3(ErgoCSetConstruction | ErgoHigh,
|
|
"add young regions to CSet",
|
|
ergo_format_region("eden")
|
|
ergo_format_region("survivors")
|
|
ergo_format_ms("predicted young region time"),
|
|
eden_region_length, survivor_region_length,
|
|
_inc_cset_predicted_elapsed_time_ms);
|
|
|
|
// The number of recorded young regions is the incremental
|
|
// collection set's current size
|
|
set_recorded_rs_lengths(_inc_cset_recorded_rs_lengths);
|
|
|
|
double young_end_time_sec = os::elapsedTime();
|
|
phase_times()->record_young_cset_choice_time_ms((young_end_time_sec - young_start_time_sec) * 1000.0);
|
|
|
|
// 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;
|
|
cset_chooser->verify();
|
|
const uint min_old_cset_length = calc_min_old_cset_length();
|
|
const uint max_old_cset_length = calc_max_old_cset_length();
|
|
|
|
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) {
|
|
// Added maximum number of old regions to the CSet.
|
|
ergo_verbose2(ErgoCSetConstruction,
|
|
"finish adding old regions to CSet",
|
|
ergo_format_reason("old CSet region num reached max")
|
|
ergo_format_region("old")
|
|
ergo_format_region("max"),
|
|
old_cset_region_length(), max_old_cset_length);
|
|
break;
|
|
}
|
|
|
|
|
|
// Stop adding regions if the remaining reclaimable space is
|
|
// not 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) {
|
|
// We've added enough old regions that the amount of uncollected
|
|
// reclaimable space is at or below the waste threshold. Stop
|
|
// adding old regions to the CSet.
|
|
ergo_verbose5(ErgoCSetConstruction,
|
|
"finish adding old regions to CSet",
|
|
ergo_format_reason("reclaimable percentage not over threshold")
|
|
ergo_format_region("old")
|
|
ergo_format_region("max")
|
|
ergo_format_byte_perc("reclaimable")
|
|
ergo_format_perc("threshold"),
|
|
old_cset_region_length(),
|
|
max_old_cset_length,
|
|
reclaimable_bytes,
|
|
reclaimable_perc, threshold);
|
|
break;
|
|
}
|
|
|
|
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.
|
|
|
|
if (old_cset_region_length() >= min_old_cset_length) {
|
|
// We have added the minimum number of old regions to the CSet,
|
|
// we are done with this CSet.
|
|
ergo_verbose4(ErgoCSetConstruction,
|
|
"finish adding old regions to CSet",
|
|
ergo_format_reason("predicted time is too high")
|
|
ergo_format_ms("predicted time")
|
|
ergo_format_ms("remaining time")
|
|
ergo_format_region("old")
|
|
ergo_format_region("min"),
|
|
predicted_time_ms, time_remaining_ms,
|
|
old_cset_region_length(), min_old_cset_length);
|
|
break;
|
|
}
|
|
|
|
// We'll add it anyway given that we haven't reached the
|
|
// minimum number of old regions.
|
|
expensive_region_num += 1;
|
|
}
|
|
} else {
|
|
if (old_cset_region_length() >= min_old_cset_length) {
|
|
// In the non-auto-tuning case, we'll finish adding regions
|
|
// to the CSet if we reach the minimum.
|
|
ergo_verbose2(ErgoCSetConstruction,
|
|
"finish adding old regions to CSet",
|
|
ergo_format_reason("old CSet region num reached min")
|
|
ergo_format_region("old")
|
|
ergo_format_region("min"),
|
|
old_cset_region_length(), min_old_cset_length);
|
|
break;
|
|
}
|
|
}
|
|
|
|
// We will add this region to the CSet.
|
|
time_remaining_ms = MAX2(time_remaining_ms - predicted_time_ms, 0.0);
|
|
predicted_pause_time_ms += predicted_time_ms;
|
|
cset_chooser->remove_and_move_to_next(hr);
|
|
_g1->old_set_remove(hr);
|
|
add_old_region_to_cset(hr);
|
|
|
|
hr = cset_chooser->peek();
|
|
}
|
|
if (hr == NULL) {
|
|
ergo_verbose0(ErgoCSetConstruction,
|
|
"finish adding old regions to CSet",
|
|
ergo_format_reason("candidate old regions not available"));
|
|
}
|
|
|
|
if (expensive_region_num > 0) {
|
|
// We print the information once here at the end, predicated on
|
|
// whether we added any apparently expensive regions or not, to
|
|
// avoid generating output per region.
|
|
ergo_verbose4(ErgoCSetConstruction,
|
|
"added expensive regions to CSet",
|
|
ergo_format_reason("old CSet region num not reached min")
|
|
ergo_format_region("old")
|
|
ergo_format_region("expensive")
|
|
ergo_format_region("min")
|
|
ergo_format_ms("remaining time"),
|
|
old_cset_region_length(),
|
|
expensive_region_num,
|
|
min_old_cset_length,
|
|
time_remaining_ms);
|
|
}
|
|
|
|
cset_chooser->verify();
|
|
}
|
|
|
|
stop_incremental_cset_building();
|
|
|
|
ergo_verbose5(ErgoCSetConstruction,
|
|
"finish choosing CSet",
|
|
ergo_format_region("eden")
|
|
ergo_format_region("survivors")
|
|
ergo_format_region("old")
|
|
ergo_format_ms("predicted pause time")
|
|
ergo_format_ms("target pause time"),
|
|
eden_region_length, survivor_region_length,
|
|
old_cset_region_length(),
|
|
predicted_pause_time_ms, target_pause_time_ms);
|
|
|
|
double non_young_end_time_sec = os::elapsedTime();
|
|
phase_times()->record_non_young_cset_choice_time_ms((non_young_end_time_sec - non_young_start_time_sec) * 1000.0);
|
|
evacuation_info.set_collectionset_regions(cset_region_length());
|
|
}
|
|
|
|
void TraceGen0TimeData::record_start_collection(double time_to_stop_the_world_ms) {
|
|
if(TraceGen0Time) {
|
|
_all_stop_world_times_ms.add(time_to_stop_the_world_ms);
|
|
}
|
|
}
|
|
|
|
void TraceGen0TimeData::record_yield_time(double yield_time_ms) {
|
|
if(TraceGen0Time) {
|
|
_all_yield_times_ms.add(yield_time_ms);
|
|
}
|
|
}
|
|
|
|
void TraceGen0TimeData::record_end_collection(double pause_time_ms, G1GCPhaseTimes* phase_times) {
|
|
if(TraceGen0Time) {
|
|
_total.add(pause_time_ms);
|
|
_other.add(pause_time_ms - phase_times->accounted_time_ms());
|
|
_root_region_scan_wait.add(phase_times->root_region_scan_wait_time_ms());
|
|
_parallel.add(phase_times->cur_collection_par_time_ms());
|
|
_ext_root_scan.add(phase_times->average_last_ext_root_scan_time());
|
|
_satb_filtering.add(phase_times->average_last_satb_filtering_times_ms());
|
|
_update_rs.add(phase_times->average_last_update_rs_time());
|
|
_scan_rs.add(phase_times->average_last_scan_rs_time());
|
|
_obj_copy.add(phase_times->average_last_obj_copy_time());
|
|
_termination.add(phase_times->average_last_termination_time());
|
|
|
|
double parallel_known_time = phase_times->average_last_ext_root_scan_time() +
|
|
phase_times->average_last_satb_filtering_times_ms() +
|
|
phase_times->average_last_update_rs_time() +
|
|
phase_times->average_last_scan_rs_time() +
|
|
phase_times->average_last_obj_copy_time() +
|
|
+ phase_times->average_last_termination_time();
|
|
|
|
double parallel_other_time = phase_times->cur_collection_par_time_ms() - parallel_known_time;
|
|
_parallel_other.add(parallel_other_time);
|
|
_clear_ct.add(phase_times->cur_clear_ct_time_ms());
|
|
}
|
|
}
|
|
|
|
void TraceGen0TimeData::increment_young_collection_count() {
|
|
if(TraceGen0Time) {
|
|
++_young_pause_num;
|
|
}
|
|
}
|
|
|
|
void TraceGen0TimeData::increment_mixed_collection_count() {
|
|
if(TraceGen0Time) {
|
|
++_mixed_pause_num;
|
|
}
|
|
}
|
|
|
|
void TraceGen0TimeData::print_summary(const char* str,
|
|
const NumberSeq* seq) const {
|
|
double sum = seq->sum();
|
|
gclog_or_tty->print_cr("%-27s = %8.2lf s (avg = %8.2lf ms)",
|
|
str, sum / 1000.0, seq->avg());
|
|
}
|
|
|
|
void TraceGen0TimeData::print_summary_sd(const char* str,
|
|
const NumberSeq* seq) const {
|
|
print_summary(str, seq);
|
|
gclog_or_tty->print_cr("%+45s = %5d, std dev = %8.2lf ms, max = %8.2lf ms)",
|
|
"(num", seq->num(), seq->sd(), seq->maximum());
|
|
}
|
|
|
|
void TraceGen0TimeData::print() const {
|
|
if (!TraceGen0Time) {
|
|
return;
|
|
}
|
|
|
|
gclog_or_tty->print_cr("ALL PAUSES");
|
|
print_summary_sd(" Total", &_total);
|
|
gclog_or_tty->print_cr("");
|
|
gclog_or_tty->print_cr("");
|
|
gclog_or_tty->print_cr(" Young GC Pauses: %8d", _young_pause_num);
|
|
gclog_or_tty->print_cr(" Mixed GC Pauses: %8d", _mixed_pause_num);
|
|
gclog_or_tty->print_cr("");
|
|
|
|
gclog_or_tty->print_cr("EVACUATION PAUSES");
|
|
|
|
if (_young_pause_num == 0 && _mixed_pause_num == 0) {
|
|
gclog_or_tty->print_cr("none");
|
|
} else {
|
|
print_summary_sd(" Evacuation Pauses", &_total);
|
|
print_summary(" Root Region Scan Wait", &_root_region_scan_wait);
|
|
print_summary(" Parallel Time", &_parallel);
|
|
print_summary(" Ext Root Scanning", &_ext_root_scan);
|
|
print_summary(" SATB Filtering", &_satb_filtering);
|
|
print_summary(" Update RS", &_update_rs);
|
|
print_summary(" Scan RS", &_scan_rs);
|
|
print_summary(" Object Copy", &_obj_copy);
|
|
print_summary(" Termination", &_termination);
|
|
print_summary(" Parallel Other", &_parallel_other);
|
|
print_summary(" Clear CT", &_clear_ct);
|
|
print_summary(" Other", &_other);
|
|
}
|
|
gclog_or_tty->print_cr("");
|
|
|
|
gclog_or_tty->print_cr("MISC");
|
|
print_summary_sd(" Stop World", &_all_stop_world_times_ms);
|
|
print_summary_sd(" Yields", &_all_yield_times_ms);
|
|
}
|
|
|
|
void TraceGen1TimeData::record_full_collection(double full_gc_time_ms) {
|
|
if (TraceGen1Time) {
|
|
_all_full_gc_times.add(full_gc_time_ms);
|
|
}
|
|
}
|
|
|
|
void TraceGen1TimeData::print() const {
|
|
if (!TraceGen1Time) {
|
|
return;
|
|
}
|
|
|
|
if (_all_full_gc_times.num() > 0) {
|
|
gclog_or_tty->print("\n%4d full_gcs: total time = %8.2f s",
|
|
_all_full_gc_times.num(),
|
|
_all_full_gc_times.sum() / 1000.0);
|
|
gclog_or_tty->print_cr(" (avg = %8.2fms).", _all_full_gc_times.avg());
|
|
gclog_or_tty->print_cr(" [std. dev = %8.2f ms, max = %8.2f ms]",
|
|
_all_full_gc_times.sd(),
|
|
_all_full_gc_times.maximum());
|
|
}
|
|
}
|