tenuring-patch

wtf-tenuring.patch

diff -r b4bdf3484720 src/share/vm/gc_implementation/g1/g1ParScanThreadState.cpp
--- a/src/share/vm/gc_implementation/g1/g1ParScanThreadState.cpp	Thu Jan 05 01:40:00 2017 +0000
+++ b/src/share/vm/gc_implementation/g1/g1ParScanThreadState.cpp	Wed Jan 18 13:35:05 2017 +0100
@@ -40,7 +40,7 @@
     _term_attempts(0),
     _tenuring_threshold(g1h->g1_policy()->tenuring_threshold()),
     _age_table(false), _scanner(g1h, rp),
-    _strong_roots_time(0), _term_time(0) {
+  _strong_roots_time(0), _term_time(0), survivorAges() {
   _scanner.set_par_scan_thread_state(this);
   // we allocate G1YoungSurvRateNumRegions plus one entries, since
   // we "sacrifice" entry 0 to keep track of surviving bytes for
@@ -104,6 +104,17 @@
                (alloc_buffer_waste + undo_waste) * HeapWordSize / K,
                alloc_buffer_waste * HeapWordSize / K,
                undo_waste * HeapWordSize / K);
+
+  std::map<KlassAndAge,int>::const_iterator it = survivorAges.begin();
+  st->print_cr("IKDEBUG >> printing ages");
+  while (it != survivorAges.end()) {
+    const char* name = InstanceKlass::cast(it->first.getKlass())->external_name();
+    if (name != NULL) {
+      st->print_cr("IKDEBUG %s - age %d - count %d", name, it->first.getAge(), it->second);
+    }
+    it++;
+  }
+  st->print_cr("IKDEBUG << printing ages");
 }
 
 #ifdef ASSERT
@@ -265,6 +276,17 @@
       obj->set_mark(old_mark);
     }
 
+    Klass* k = obj->klass_or_null();
+    if (k != NULL) {
+      const KlassAndAge key(k, age);
+      std::map<KlassAndAge,int>::iterator it = survivorAges.find(key);
+      if (it != survivorAges.end()) {
+	it->second = it->second + 1;
+      } else {
+	survivorAges.insert(std::make_pair(key, 1));
+      }
+    }
+
     if (G1StringDedup::is_enabled()) {
       const bool is_from_young = state.is_young();
       const bool is_to_young = dest_state.is_young();
diff -r b4bdf3484720 src/share/vm/gc_implementation/g1/g1ParScanThreadState.hpp
--- a/src/share/vm/gc_implementation/g1/g1ParScanThreadState.hpp	Thu Jan 05 01:40:00 2017 +0000
+++ b/src/share/vm/gc_implementation/g1/g1ParScanThreadState.hpp	Wed Jan 18 13:35:05 2017 +0100
@@ -35,9 +35,32 @@
 #include "memory/allocation.hpp"
 #include "oops/oop.hpp"
 
+#include <map>
+#include <string>
+#include <functional>
+
 class HeapRegion;
 class outputStream;
 
+class KlassAndAge {
+private:
+  Klass* klass;
+  int age;
+
+public:
+
+  KlassAndAge(Klass* _klass, int _age) : klass(_klass), age(_age) {}
+
+  bool operator<(KlassAndAge const& right) const {
+    return (this->klass < right.klass)
+      || (this->klass == right.klass && this->age < right.age);
+  }
+
+  Klass* getKlass() const { return klass; }
+  int getAge() const { return age; }
+};
+
+
 class G1ParScanThreadState : public StackObj {
  private:
   G1CollectedHeap* _g1h;
@@ -93,6 +116,8 @@
   }
 
  public:
+  std::map<KlassAndAge,int> survivorAges;
+
   G1ParScanThreadState(G1CollectedHeap* g1h, uint queue_num, ReferenceProcessor* rp);
   ~G1ParScanThreadState();