--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp	Tue Nov 18 11:10:02 2014 +0000
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp	Tue Nov 18 12:33:47 2014 +0000
@@ -192,7 +192,6 @@
      FreeBlockDictionary<FreeChunk>::DictionaryChoice dictionaryChoice) :
   CardGeneration(rs, initial_byte_size, level, ct),
   _dilatation_factor(((double)MinChunkSize)/((double)(CollectedHeap::min_fill_size()))),
-  _debug_concurrent_cycle(true),
   _did_compact(false)
 {
   HeapWord* bottom = (HeapWord*) _virtual_space.low();
@@ -1245,14 +1244,6 @@
     return true;
   }
 
-  // For debugging purposes, change the type of collection.
-  // Rotate between concurrent and stop-the-world full GCs.
-  NOT_PRODUCT(
-    if (RotateCMSCollectionTypes) {
-      return _cmsGen->debug_concurrent_cycle();
-    }
-  )
-
   FreelistLocker x(this);
   // ------------------------------------------------------------------
   // Print out lots of information which affects the initiation of
@@ -5830,17 +5821,6 @@
   }
 }
 
-void ConcurrentMarkSweepGeneration::rotate_debug_collection_type() {
-  if (PrintGCDetails && Verbose) {
-    if (_debug_concurrent_cycle) {
-      gclog_or_tty->print_cr("Rotate from concurrent to STW collections");
-    } else {
-      gclog_or_tty->print_cr("Rotate from STW to concurrent collections");
-    }
-  }
-  _debug_concurrent_cycle = !_debug_concurrent_cycle;
-}
-
 void CMSCollector::sweepWork(ConcurrentMarkSweepGeneration* gen) {
   // We iterate over the space(s) underlying this generation,
   // checking the mark bit map to see if the bits corresponding
@@ -5961,12 +5941,6 @@
     _collectorState = Idling;
   }
 
-  NOT_PRODUCT(
-    if (RotateCMSCollectionTypes) {
-      _cmsGen->rotate_debug_collection_type();
-    }
-  )
-
   register_gc_end();
 }
 

--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp	Tue Nov 18 11:10:02 2014 +0000
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp	Tue Nov 18 12:33:47 2014 +0000
@@ -1040,8 +1040,6 @@
   // In support of MinChunkSize being larger than min object size
   const double _dilatation_factor;
 
-  bool _debug_concurrent_cycle;
-
   // True if a compacting collection was done.
   bool _did_compact;
   bool did_compact() { return _did_compact; }
@@ -1268,9 +1266,6 @@
   // Resize the generation after a non-compacting
   // collection.
   void compute_new_size_free_list();
-
-  bool debug_concurrent_cycle() { return _debug_concurrent_cycle; }
-  void rotate_debug_collection_type();
 };
 
 //

--- a/hotspot/src/share/vm/runtime/globals.hpp	Tue Nov 18 11:10:02 2014 +0000
+++ b/hotspot/src/share/vm/runtime/globals.hpp	Tue Nov 18 12:33:47 2014 +0000
@@ -1523,9 +1523,6 @@
   develop(bool, UseAsyncConcMarkSweepGC, true,                              \
           "Use Asynchronous Concurrent Mark-Sweep GC in the old generation")\
                                                                             \
-  develop(bool, RotateCMSCollectionTypes, false,                            \
-          "Rotate the CMS collections among concurrent and STW")            \
-                                                                            \
   product(bool, UseCMSBestFit, true,                                        \
           "Use CMS best fit allocation strategy")                           \
                                                                             \