8015268: NPG: 2.5% regression in young GC times on CRM Sales Opty
Summary: Split SystemDictionary and ClassLoaderDataGraph root processing to help load balancing.
Reviewed-by: tschatzl, johnc
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.cpp Fri May 24 14:16:41 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.cpp Mon May 27 15:22:59 2013 +0200
@@ -120,6 +120,9 @@
case system_dictionary:
SystemDictionary::always_strong_oops_do(&mark_and_push_closure);
+ break;
+
+ case class_loader_data:
ClassLoaderDataGraph::always_strong_oops_do(&mark_and_push_closure, &follow_klass_closure, true);
break;
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.hpp Fri May 24 14:16:41 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.hpp Mon May 27 15:22:59 2013 +0200
@@ -98,7 +98,8 @@
management = 6,
jvmti = 7,
system_dictionary = 8,
- code_cache = 9
+ class_loader_data = 9,
+ code_cache = 10
};
private:
RootType _root_type;
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp Fri May 24 14:16:41 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp Mon May 27 15:22:59 2013 +0200
@@ -2338,6 +2338,7 @@
q->enqueue(new MarkFromRootsTask(MarkFromRootsTask::flat_profiler));
q->enqueue(new MarkFromRootsTask(MarkFromRootsTask::management));
q->enqueue(new MarkFromRootsTask(MarkFromRootsTask::system_dictionary));
+ q->enqueue(new MarkFromRootsTask(MarkFromRootsTask::class_loader_data));
q->enqueue(new MarkFromRootsTask(MarkFromRootsTask::jvmti));
q->enqueue(new MarkFromRootsTask(MarkFromRootsTask::code_cache));
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Fri May 24 14:16:41 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Mon May 27 15:22:59 2013 +0200
@@ -408,6 +408,7 @@
q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::flat_profiler));
q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::management));
q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::system_dictionary));
+ q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::class_loader_data));
q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::jvmti));
q->enqueue(new ScavengeRootsTask(ScavengeRootsTask::code_cache));
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psTasks.cpp Fri May 24 14:16:41 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psTasks.cpp Mon May 27 15:22:59 2013 +0200
@@ -79,14 +79,15 @@
break;
case system_dictionary:
- {
SystemDictionary::oops_do(&roots_closure);
+ break;
- // Move this to another root_type?
- PSScavengeKlassClosure klass_closure(pm);
- ClassLoaderDataGraph::oops_do(&roots_closure, &klass_closure, false);
- }
- break;
+ case class_loader_data:
+ {
+ PSScavengeKlassClosure klass_closure(pm);
+ ClassLoaderDataGraph::oops_do(&roots_closure, &klass_closure, false);
+ }
+ break;
case management:
Management::oops_do(&roots_closure);
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psTasks.hpp Fri May 24 14:16:41 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psTasks.hpp Mon May 27 15:22:59 2013 +0200
@@ -59,9 +59,10 @@
object_synchronizer = 4,
flat_profiler = 5,
system_dictionary = 6,
- management = 7,
- jvmti = 8,
- code_cache = 9
+ class_loader_data = 7,
+ management = 8,
+ jvmti = 9,
+ code_cache = 10
};
private:
RootType _root_type;
--- a/hotspot/src/share/vm/memory/sharedHeap.cpp Fri May 24 14:16:41 2013 +0200
+++ b/hotspot/src/share/vm/memory/sharedHeap.cpp Mon May 27 15:22:59 2013 +0200
@@ -45,6 +45,7 @@
SH_PS_FlatProfiler_oops_do,
SH_PS_Management_oops_do,
SH_PS_SystemDictionary_oops_do,
+ SH_PS_ClassLoaderDataGraph_oops_do,
SH_PS_jvmti_oops_do,
SH_PS_StringTable_oops_do,
SH_PS_CodeCache_oops_do,
@@ -173,15 +174,21 @@
if (!_process_strong_tasks->is_task_claimed(SH_PS_SystemDictionary_oops_do)) {
if (so & SO_AllClasses) {
SystemDictionary::oops_do(roots);
- ClassLoaderDataGraph::oops_do(roots, klass_closure, !is_scavenging);
} else if (so & SO_SystemClasses) {
SystemDictionary::always_strong_oops_do(roots);
- ClassLoaderDataGraph::always_strong_oops_do(roots, klass_closure, !is_scavenging);
} else {
fatal("We should always have selected either SO_AllClasses or SO_SystemClasses");
}
}
+ if (!_process_strong_tasks->is_task_claimed(SH_PS_ClassLoaderDataGraph_oops_do)) {
+ if (so & SO_AllClasses) {
+ ClassLoaderDataGraph::oops_do(roots, klass_closure, !is_scavenging);
+ } else if (so & SO_SystemClasses) {
+ ClassLoaderDataGraph::always_strong_oops_do(roots, klass_closure, !is_scavenging);
+ }
+ }
+
if (!_process_strong_tasks->is_task_claimed(SH_PS_StringTable_oops_do)) {
if (so & SO_Strings) {
StringTable::oops_do(roots);