--- old/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp	2013-05-09 12:17:37.328431287 +0200
+++ new/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp	2013-05-09 12:17:37.252431288 +0200
@@ -62,7 +62,8 @@
 
 // statics
 CMSCollector* ConcurrentMarkSweepGeneration::_collector = NULL;
-bool          CMSCollector::_full_gc_requested          = false;
+bool CMSCollector::_full_gc_requested = false;
+GCCause::Cause CMSCollector::_full_gc_cause = GCCause::_no_gc;
 
 //////////////////////////////////////////////////////////////////
 // In support of CMS/VM thread synchronization
@@ -1683,12 +1684,13 @@
 
 }
 
-void CMSCollector::request_full_gc(unsigned int full_gc_count) {
+void CMSCollector::request_full_gc(unsigned int full_gc_count, GCCause::Cause cause) {
   GenCollectedHeap* gch = GenCollectedHeap::heap();
   unsigned int gc_count = gch->total_full_collections();
   if (gc_count == full_gc_count) {
     MutexLockerEx y(CGC_lock, Mutex::_no_safepoint_check_flag);
     _full_gc_requested = true;
+    _full_gc_cause = cause;
     CGC_lock->notify();   // nudge CMS thread
   } else {
     assert(gc_count > full_gc_count, "Error: causal loop");
@@ -2205,7 +2207,9 @@
     } else {
       assert(_collectorState == Idling, "Should be idling before start.");
       _collectorState = InitialMarking;
-      register_gc_start(GCCause::_cms_concurrent_mark);
+      GCCause::Cause cause =
+        _full_gc_requested ? _full_gc_cause : GCCause::_cms_concurrent_mark;
+      register_gc_start(cause);
       // Reset the expansion cause, now that we are about to begin
       // a new cycle.
       clear_expansion_cause();
@@ -2214,6 +2218,7 @@
     // ensuing concurrent GC cycle.
     update_should_unload_classes();
     _full_gc_requested = false;           // acks all outstanding full gc requests
+    _full_gc_cause = GCCause::_no_gc;
     // Signal that we are about to start a collection
     gch->increment_total_full_collections();  // ... starting a collection cycle
     _collection_count_start = gch->total_full_collections();
--- old/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp	2013-05-09 12:17:37.816431282 +0200
+++ new/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp	2013-05-09 12:17:37.744431284 +0200
@@ -573,8 +573,9 @@
   bool _completed_initialization;
 
   // In support of ExplicitGCInvokesConcurrent
-  static   bool _full_gc_requested;
-  unsigned int  _collection_count_start;
+  static bool _full_gc_requested;
+  static GCCause::Cause _full_gc_cause;
+  unsigned int _collection_count_start;
 
   // Should we unload classes this concurrent cycle?
   bool _should_unload_classes;
@@ -909,7 +910,7 @@
   void collect_in_foreground(bool clear_all_soft_refs);
 
   // In support of ExplicitGCInvokesConcurrent
-  static void request_full_gc(unsigned int full_gc_count);
+  static void request_full_gc(unsigned int full_gc_count, GCCause::Cause cause);
   // Should we unload classes in a particular concurrent cycle?
   bool should_unload_classes() const {
     return _should_unload_classes;
--- old/src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.cpp	2013-05-09 12:17:38.228431277 +0200
+++ new/src/share/vm/gc_implementation/concurrentMarkSweep/vmCMSOperations.cpp	2013-05-09 12:17:38.152431278 +0200
@@ -241,7 +241,7 @@
     // In case CMS thread was in icms_wait(), wake it up.
     CMSCollector::start_icms();
     // Nudge the CMS thread to start a concurrent collection.
-    CMSCollector::request_full_gc(_full_gc_count_before);
+    CMSCollector::request_full_gc(_full_gc_count_before, _gc_cause);
   } else {
     assert(_full_gc_count_before < gch->total_full_collections(), "Error");
     FullGCCount_lock->notify_all();  // Inform the Java thread its work is done