diff --git a/src/hotspot/share/gc/g1/g1CollectionSetCandidates.cpp b/src/hotspot/share/gc/g1/g1CollectionSetCandidates.cpp
index b4649414b10e6..36a194bdfb0ec 100644
--- a/src/hotspot/share/gc/g1/g1CollectionSetCandidates.cpp
+++ b/src/hotspot/share/gc/g1/g1CollectionSetCandidates.cpp
@@ -23,7 +23,7 @@
*/
#include "precompiled.hpp"
-#include "gc/g1/g1CollectionSetCandidates.hpp"
+#include "gc/g1/g1CollectionSetCandidates.inline.hpp"
#include "gc/g1/g1CollectionSetChooser.hpp"
#include "gc/g1/g1HeapRegion.inline.hpp"
#include "utilities/bitMap.inline.hpp"
@@ -44,7 +44,7 @@ void G1CollectionCandidateList::append_unsorted(HeapRegion* r) {
}
void G1CollectionCandidateList::sort_by_efficiency() {
- _candidates.sort(compare);
+ _candidates.sort(compare_gc_efficiency);
}
void G1CollectionCandidateList::remove(G1CollectionCandidateRegionList* other) {
@@ -94,7 +94,22 @@ void G1CollectionCandidateList::verify() {
}
#endif
-int G1CollectionCandidateList::compare(G1CollectionSetCandidateInfo* ci1, G1CollectionSetCandidateInfo* ci2) {
+int G1CollectionCandidateList::compare_gc_efficiency(G1CollectionSetCandidateInfo* ci1, G1CollectionSetCandidateInfo* ci2) {
+ assert(ci1->_r != nullptr && ci2->_r != nullptr, "Should not be!");
+
+ double gc_eff1 = ci1->_gc_efficiency;
+ double gc_eff2 = ci2->_gc_efficiency;
+
+ if (gc_eff1 > gc_eff2) {
+ return -1;
+ } else if (gc_eff1 < gc_eff2) {
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+int G1CollectionCandidateList::compare_reclaimble_bytes(G1CollectionSetCandidateInfo* ci1, G1CollectionSetCandidateInfo* ci2) {
// Make sure that null entries are moved to the end.
if (ci1->_r == nullptr) {
if (ci2->_r == nullptr) {
@@ -106,12 +121,12 @@ int G1CollectionCandidateList::compare(G1CollectionSetCandidateInfo* ci1, G1Coll
return -1;
}
- double gc_eff1 = ci1->_gc_efficiency;
- double gc_eff2 = ci2->_gc_efficiency;
+ size_t reclaimable1 = ci1->_r->reclaimable_bytes();
+ size_t reclaimable2 = ci2->_r->reclaimable_bytes();
- if (gc_eff1 > gc_eff2) {
+ if (reclaimable1 > reclaimable2) {
return -1;
- } if (gc_eff1 < gc_eff2) {
+ } else if (reclaimable1 < reclaimable2) {
return 1;
} else {
return 0;
@@ -182,6 +197,17 @@ void G1CollectionSetCandidates::clear() {
_last_marking_candidates_length = 0;
}
+void G1CollectionSetCandidates::sort_marking_by_efficiency() {
+ G1CollectionCandidateListIterator iter = _marking_regions.begin();
+ for (; iter != _marking_regions.end(); ++iter) {
+ HeapRegion* hr = (*iter)->_r;
+ (*iter)->_gc_efficiency = hr->calc_gc_efficiency();
+ }
+ _marking_regions.sort_by_efficiency();
+
+ _marking_regions.verify();
+}
+
void G1CollectionSetCandidates::set_candidates_from_marking(G1CollectionSetCandidateInfo* candidate_infos,
uint num_infos) {
assert(_marking_regions.length() == 0, "must be empty before adding new ones");
diff --git a/src/hotspot/share/gc/g1/g1CollectionSetCandidates.hpp b/src/hotspot/share/gc/g1/g1CollectionSetCandidates.hpp
index 4eb5523d0399e..dd38d33b5d39e 100644
--- a/src/hotspot/share/gc/g1/g1CollectionSetCandidates.hpp
+++ b/src/hotspot/share/gc/g1/g1CollectionSetCandidates.hpp
@@ -129,7 +129,9 @@ class G1CollectionCandidateList : public CHeapObj<mtGC> {
// Comparison function to order regions in decreasing GC efficiency order. This
// will cause regions with a lot of live objects and large remembered sets to end
// up at the end of the list.
- static int compare(G1CollectionSetCandidateInfo* ci1, G1CollectionSetCandidateInfo* ci2);
+ static int compare_gc_efficiency(G1CollectionSetCandidateInfo* ci1, G1CollectionSetCandidateInfo* ci2);
+
+ static int compare_reclaimble_bytes(G1CollectionSetCandidateInfo* ci1, G1CollectionSetCandidateInfo* ci2);
G1CollectionCandidateListIterator begin() {
return G1CollectionCandidateListIterator(this, 0);
@@ -213,6 +215,8 @@ class G1CollectionSetCandidates : public CHeapObj<mtGC> {
void sort_by_efficiency();
+ void sort_marking_by_efficiency();
+
// Add the given region to the set of retained regions without regards to the
// gc efficiency sorting. The retained regions must be re-sorted manually later.
void add_retained_region_unsorted(HeapRegion* r);
diff --git a/src/hotspot/share/gc/g1/g1CollectionSetChooser.cpp b/src/hotspot/share/gc/g1/g1CollectionSetChooser.cpp
index 92a342ec7579d..df3e72cb22f37 100644
--- a/src/hotspot/share/gc/g1/g1CollectionSetChooser.cpp
+++ b/src/hotspot/share/gc/g1/g1CollectionSetChooser.cpp
@@ -94,17 +94,17 @@ class G1BuildCandidateRegionsTask : public WorkerTask {
void set(uint idx, HeapRegion* hr) {
assert(idx < _max_size, "Index %u out of bounds %u", idx, _max_size);
assert(_data[idx]._r == nullptr, "Value must not have been set.");
- _data[idx] = CandidateInfo(hr, hr->calc_gc_efficiency());
+ _data[idx] = CandidateInfo(hr, 0.0);
}
- void sort_by_efficiency() {
+ void sort_by_reclaimable_bytes() {
if (_cur_claim_idx == 0) {
return;
}
for (uint i = _cur_claim_idx; i < _max_size; i++) {
assert(_data[i]._r == nullptr, "must be");
}
- qsort(_data, _cur_claim_idx, sizeof(_data[0]), (_sort_Fn)G1CollectionCandidateList::compare);
+ qsort(_data, _cur_claim_idx, sizeof(_data[0]), (_sort_Fn)G1CollectionCandidateList::compare_reclaimble_bytes);
for (uint i = _cur_claim_idx; i < _max_size; i++) {
assert(_data[i]._r == nullptr, "must be");
}
@@ -152,8 +152,7 @@ class G1BuildCandidateRegionsTask : public WorkerTask {
}
// Can not add a region without a remembered set to the candidates.
- assert(!r->rem_set()->is_updating(), "must be");
- if (!r->rem_set()->is_complete()) {
+ if (!r->rem_set()->is_tracked()) {
return false;
}
@@ -249,7 +248,7 @@ class G1BuildCandidateRegionsTask : public WorkerTask {
}
void sort_and_prune_into(G1CollectionSetCandidates* candidates) {
- _result.sort_by_efficiency();
+ _result.sort_by_reclaimable_bytes();
prune(_result.array());
candidates->set_candidates_from_marking(_result.array(),
_num_regions_added);
diff --git a/src/hotspot/share/gc/g1/g1ConcurrentMark.cpp b/src/hotspot/share/gc/g1/g1ConcurrentMark.cpp
index fdb380ae99f28..ba21f4025dd26 100644
--- a/src/hotspot/share/gc/g1/g1ConcurrentMark.cpp
+++ b/src/hotspot/share/gc/g1/g1ConcurrentMark.cpp
@@ -1437,7 +1437,14 @@ void G1ConcurrentMark::remark() {
log_debug(gc, remset, tracking)("Remembered Set Tracking update regions total %u, selected %u",
_g1h->num_regions(), cl.total_selected_for_rebuild());
+
_needs_remembered_set_rebuild = (cl.total_selected_for_rebuild() > 0);
+
+ if (_needs_remembered_set_rebuild) {
+ // Prune rebuild candidates based on G1HeapWastePercent.
+ // Improves rebuild time in addition to remembered set memory usage.
+ G1CollectionSetChooser::build(_g1h->workers(), _g1h->num_regions(), _g1h->policy()->candidates());
+ }
}
if (log_is_enabled(Trace, gc, liveness)) {
diff --git a/src/hotspot/share/gc/g1/g1Policy.cpp b/src/hotspot/share/gc/g1/g1Policy.cpp
index dd9d937ad77b5..b27ddd0a9bb0e 100644
--- a/src/hotspot/share/gc/g1/g1Policy.cpp
+++ b/src/hotspot/share/gc/g1/g1Policy.cpp
@@ -1310,7 +1310,7 @@ void G1Policy::decide_on_concurrent_start_pause() {
void G1Policy::record_concurrent_mark_cleanup_end(bool has_rebuilt_remembered_sets) {
bool mixed_gc_pending = false;
if (has_rebuilt_remembered_sets) {
- G1CollectionSetChooser::build(_g1h->workers(), _g1h->num_regions(), candidates());
+ candidates()->sort_marking_by_efficiency();
mixed_gc_pending = next_gc_should_be_mixed();
}
diff --git a/src/hotspot/share/gc/g1/g1Policy.hpp b/src/hotspot/share/gc/g1/g1Policy.hpp
index c951909788c2e..43759dc476778 100644
--- a/src/hotspot/share/gc/g1/g1Policy.hpp
+++ b/src/hotspot/share/gc/g1/g1Policy.hpp
@@ -184,9 +184,10 @@ class G1Policy: public CHeapObj<mtGC> {
return _mmu_tracker->max_gc_time() * 1000.0;
}
+ G1CollectionSetCandidates* candidates() const;
+
private:
G1CollectionSet* _collection_set;
- G1CollectionSetCandidates* candidates() const;
double average_time_ms(G1GCPhaseTimes::GCParPhases phase) const;
double other_time_ms(double pause_time_ms) const;