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/*
* Copyright (c) 2018, 2020, Red Hat, Inc. All rights reserved.
+ * Copyright Amazon.com Inc. 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.
*
*/
#include "precompiled.hpp"
#include "gc/shared/gcCause.hpp"
- #include "gc/shenandoah/shenandoahCollectionSet.inline.hpp"
#include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
- #include "gc/shenandoah/shenandoahHeap.inline.hpp"
#include "gc/shenandoah/shenandoahHeapRegion.inline.hpp"
#include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
#include "gc/shenandoah/heuristics/shenandoahHeuristics.hpp"
#include "logging/log.hpp"
#include "logging/logTag.hpp"
#include "runtime/globals_extension.hpp"
int ShenandoahHeuristics::compare_by_garbage(RegionData a, RegionData b) {
! if (a._garbage > b._garbage)
return -1;
! else if (a._garbage < b._garbage)
return 1;
else return 0;
}
ShenandoahHeuristics::ShenandoahHeuristics(ShenandoahSpaceInfo* space_info) :
_space_info(space_info),
_region_data(nullptr),
_degenerated_cycles_in_a_row(0),
_successful_cycles_in_a_row(0),
_cycle_start(os::elapsedTime()),
_last_cycle_end(0),
_gc_times_learned(0),
_gc_time_penalties(0),
! _gc_time_history(new TruncatedSeq(10, ShenandoahAdaptiveDecayFactor)),
_metaspace_oom()
{
// No unloading during concurrent mark? Communicate that to heuristics
if (!ClassUnloadingWithConcurrentMark) {
FLAG_SET_DEFAULT(ShenandoahUnloadClassesFrequency, 0);
*
*/
#include "precompiled.hpp"
#include "gc/shared/gcCause.hpp"
#include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
#include "gc/shenandoah/shenandoahHeapRegion.inline.hpp"
#include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
#include "gc/shenandoah/heuristics/shenandoahHeuristics.hpp"
#include "logging/log.hpp"
#include "logging/logTag.hpp"
#include "runtime/globals_extension.hpp"
+ #include "utilities/quickSort.hpp"
+ // sort by decreasing garbage (so most garbage comes first)
int ShenandoahHeuristics::compare_by_garbage(RegionData a, RegionData b) {
! if (a._u._garbage > b._u._garbage)
return -1;
! else if (a._u._garbage < b._u._garbage)
return 1;
else return 0;
}
ShenandoahHeuristics::ShenandoahHeuristics(ShenandoahSpaceInfo* space_info) :
_space_info(space_info),
_region_data(nullptr),
_degenerated_cycles_in_a_row(0),
_successful_cycles_in_a_row(0),
+ _guaranteed_gc_interval(0),
_cycle_start(os::elapsedTime()),
_last_cycle_end(0),
_gc_times_learned(0),
_gc_time_penalties(0),
! _gc_cycle_time_history(new TruncatedSeq(Moving_Average_Samples, ShenandoahAdaptiveDecayFactor)),
_metaspace_oom()
{
// No unloading during concurrent mark? Communicate that to heuristics
if (!ClassUnloadingWithConcurrentMark) {
FLAG_SET_DEFAULT(ShenandoahUnloadClassesFrequency, 0);
ShenandoahHeuristics::~ShenandoahHeuristics() {
FREE_C_HEAP_ARRAY(RegionGarbage, _region_data);
}
void ShenandoahHeuristics::choose_collection_set(ShenandoahCollectionSet* collection_set) {
! assert(collection_set->count() == 0, "Must be empty");
ShenandoahHeap* heap = ShenandoahHeap::heap();
// Check all pinned regions have updated status before choosing the collection set.
heap->assert_pinned_region_status();
ShenandoahHeuristics::~ShenandoahHeuristics() {
FREE_C_HEAP_ARRAY(RegionGarbage, _region_data);
}
void ShenandoahHeuristics::choose_collection_set(ShenandoahCollectionSet* collection_set) {
! assert(collection_set->is_empty(), "Must be empty");
ShenandoahHeap* heap = ShenandoahHeap::heap();
// Check all pinned regions have updated status before choosing the collection set.
heap->assert_pinned_region_status();
immediate_garbage += garbage;
region->make_trash_immediate();
} else {
// This is our candidate for later consideration.
candidates[cand_idx]._region = region;
! candidates[cand_idx]._garbage = garbage;
cand_idx++;
}
} else if (region->is_humongous_start()) {
// Reclaim humongous regions here, and count them as the immediate garbage
#ifdef ASSERT
immediate_garbage += garbage;
region->make_trash_immediate();
} else {
// This is our candidate for later consideration.
candidates[cand_idx]._region = region;
! candidates[cand_idx]._u._garbage = garbage;
cand_idx++;
}
} else if (region->is_humongous_start()) {
// Reclaim humongous regions here, and count them as the immediate garbage
#ifdef ASSERT
size_t immediate_percent = (total_garbage == 0) ? 0 : (immediate_garbage * 100 / total_garbage);
if (immediate_percent <= ShenandoahImmediateThreshold) {
choose_collection_set_from_regiondata(collection_set, candidates, cand_idx, immediate_garbage + free);
}
size_t cset_percent = (total_garbage == 0) ? 0 : (collection_set->garbage() * 100 / total_garbage);
-
size_t collectable_garbage = collection_set->garbage() + immediate_garbage;
size_t collectable_garbage_percent = (total_garbage == 0) ? 0 : (collectable_garbage * 100 / total_garbage);
log_info(gc, ergo)("Collectable Garbage: " SIZE_FORMAT "%s (" SIZE_FORMAT "%%), "
! "Immediate: " SIZE_FORMAT "%s (" SIZE_FORMAT "%%), "
! "CSet: " SIZE_FORMAT "%s (" SIZE_FORMAT "%%)",
byte_size_in_proper_unit(collectable_garbage),
proper_unit_for_byte_size(collectable_garbage),
collectable_garbage_percent,
byte_size_in_proper_unit(immediate_garbage),
proper_unit_for_byte_size(immediate_garbage),
immediate_percent,
byte_size_in_proper_unit(collection_set->garbage()),
proper_unit_for_byte_size(collection_set->garbage()),
! cset_percent);
}
void ShenandoahHeuristics::record_cycle_start() {
_cycle_start = os::elapsedTime();
}
size_t immediate_percent = (total_garbage == 0) ? 0 : (immediate_garbage * 100 / total_garbage);
if (immediate_percent <= ShenandoahImmediateThreshold) {
choose_collection_set_from_regiondata(collection_set, candidates, cand_idx, immediate_garbage + free);
+ } else {
+ // We are going to skip evacuation and update refs because we reclaimed
+ // sufficient amounts of immediate garbage.
+ heap->shenandoah_policy()->record_abbreviated_cycle();
}
size_t cset_percent = (total_garbage == 0) ? 0 : (collection_set->garbage() * 100 / total_garbage);
size_t collectable_garbage = collection_set->garbage() + immediate_garbage;
size_t collectable_garbage_percent = (total_garbage == 0) ? 0 : (collectable_garbage * 100 / total_garbage);
log_info(gc, ergo)("Collectable Garbage: " SIZE_FORMAT "%s (" SIZE_FORMAT "%%), "
! "Immediate: " SIZE_FORMAT "%s (" SIZE_FORMAT "%%), " SIZE_FORMAT " regions, "
! "CSet: " SIZE_FORMAT "%s (" SIZE_FORMAT "%%), " SIZE_FORMAT " regions",
byte_size_in_proper_unit(collectable_garbage),
proper_unit_for_byte_size(collectable_garbage),
collectable_garbage_percent,
byte_size_in_proper_unit(immediate_garbage),
proper_unit_for_byte_size(immediate_garbage),
immediate_percent,
+ immediate_regions,
byte_size_in_proper_unit(collection_set->garbage()),
proper_unit_for_byte_size(collection_set->garbage()),
! cset_percent,
+ collection_set->count());
}
void ShenandoahHeuristics::record_cycle_start() {
_cycle_start = os::elapsedTime();
}
// Some of vmTestbase/metaspace tests depend on following line to count GC cycles
log_info(gc)("Trigger: %s", GCCause::to_string(GCCause::_metadata_GC_threshold));
return true;
}
! if (ShenandoahGuaranteedGCInterval > 0) {
double last_time_ms = (os::elapsedTime() - _last_cycle_end) * 1000;
! if (last_time_ms > ShenandoahGuaranteedGCInterval) {
! log_info(gc)("Trigger: Time since last GC (%.0f ms) is larger than guaranteed interval (" UINTX_FORMAT " ms)",
! last_time_ms, ShenandoahGuaranteedGCInterval);
return true;
}
}
return false;
// Some of vmTestbase/metaspace tests depend on following line to count GC cycles
log_info(gc)("Trigger: %s", GCCause::to_string(GCCause::_metadata_GC_threshold));
return true;
}
! if (_guaranteed_gc_interval > 0) {
double last_time_ms = (os::elapsedTime() - _last_cycle_end) * 1000;
! if (last_time_ms > _guaranteed_gc_interval) {
! log_info(gc)("Trigger (%s): Time since last GC (%.0f ms) is larger than guaranteed interval (" UINTX_FORMAT " ms)",
! _space_info->name(), last_time_ms, _guaranteed_gc_interval);
return true;
}
}
return false;
return _degenerated_cycles_in_a_row <= ShenandoahFullGCThreshold;
}
void ShenandoahHeuristics::adjust_penalty(intx step) {
assert(0 <= _gc_time_penalties && _gc_time_penalties <= 100,
! "In range before adjustment: " INTX_FORMAT, _gc_time_penalties);
intx new_val = _gc_time_penalties + step;
if (new_val < 0) {
new_val = 0;
}
return _degenerated_cycles_in_a_row <= ShenandoahFullGCThreshold;
}
void ShenandoahHeuristics::adjust_penalty(intx step) {
assert(0 <= _gc_time_penalties && _gc_time_penalties <= 100,
! "In range before adjustment: " INTX_FORMAT, _gc_time_penalties);
intx new_val = _gc_time_penalties + step;
if (new_val < 0) {
new_val = 0;
}
new_val = 100;
}
_gc_time_penalties = new_val;
assert(0 <= _gc_time_penalties && _gc_time_penalties <= 100,
! "In range after adjustment: " INTX_FORMAT, _gc_time_penalties);
}
! void ShenandoahHeuristics::record_success_concurrent() {
_degenerated_cycles_in_a_row = 0;
_successful_cycles_in_a_row++;
-
- _gc_time_history->add(time_since_last_gc());
_gc_times_learned++;
adjust_penalty(Concurrent_Adjust);
}
void ShenandoahHeuristics::record_success_degenerated() {
_degenerated_cycles_in_a_row++;
_successful_cycles_in_a_row = 0;
new_val = 100;
}
_gc_time_penalties = new_val;
assert(0 <= _gc_time_penalties && _gc_time_penalties <= 100,
! "In range after adjustment: " INTX_FORMAT, _gc_time_penalties);
}
! void ShenandoahHeuristics::record_success_concurrent(bool abbreviated) {
_degenerated_cycles_in_a_row = 0;
_successful_cycles_in_a_row++;
_gc_times_learned++;
adjust_penalty(Concurrent_Adjust);
+
+ if (_gc_times_learned <= ShenandoahLearningSteps || !(abbreviated && ShenandoahAdaptiveIgnoreShortCycles)) {
+ _gc_cycle_time_history->add(elapsed_cycle_time());
+ }
}
void ShenandoahHeuristics::record_success_degenerated() {
_degenerated_cycles_in_a_row++;
_successful_cycles_in_a_row = 0;
void ShenandoahHeuristics::initialize() {
// Nothing to do by default.
}
! double ShenandoahHeuristics::time_since_last_gc() const {
return os::elapsedTime() - _cycle_start;
}
void ShenandoahHeuristics::initialize() {
// Nothing to do by default.
}
! double ShenandoahHeuristics::elapsed_cycle_time() const {
return os::elapsedTime() - _cycle_start;
}
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