142   friend class G1CheckCSetFastTableClosure;
 143 
 144 private:
 145   WorkGang* _workers;
 146   G1CollectorPolicy* _collector_policy;
 147 
 148   static size_t _humongous_object_threshold_in_words;
 149 
 150   // The secondary free list which contains regions that have been
 151   // freed up during the cleanup process. This will be appended to
 152   // the master free list when appropriate.
 153   FreeRegionList _secondary_free_list;
 154 
 155   // It keeps track of the old regions.
 156   HeapRegionSet _old_set;
 157 
 158   // It keeps track of the humongous regions.
 159   HeapRegionSet _humongous_set;
 160 
 161   void eagerly_reclaim_humongous_regions();


 162 
 163   // The number of regions we could create by expansion.
 164   uint _expansion_regions;
 165 
 166   // The block offset table for the G1 heap.
 167   G1BlockOffsetTable* _bot;
 168 
 169   // Tears down the region sets / lists so that they are empty and the
 170   // regions on the heap do not belong to a region set / list. The
 171   // only exception is the humongous set which we leave unaltered. If
 172   // free_list_only is true, it will only tear down the master free
 173   // list. It is called before a Full GC (free_list_only == false) or
 174   // before heap shrinking (free_list_only == true).
 175   void tear_down_region_sets(bool free_list_only);
 176 
 177   // Rebuilds the region sets / lists so that they are repopulated to
 178   // reflect the contents of the heap. The only exception is the
 179   // humongous set which was not torn down in the first place. If
 180   // free_list_only is true, it will only rebuild the master free
 181   // list. It is called after a Full GC (free_list_only == false) or

 142   friend class G1CheckCSetFastTableClosure;
 143 
 144 private:
 145   WorkGang* _workers;
 146   G1CollectorPolicy* _collector_policy;
 147 
 148   static size_t _humongous_object_threshold_in_words;
 149 
 150   // The secondary free list which contains regions that have been
 151   // freed up during the cleanup process. This will be appended to
 152   // the master free list when appropriate.
 153   FreeRegionList _secondary_free_list;
 154 
 155   // It keeps track of the old regions.
 156   HeapRegionSet _old_set;
 157 
 158   // It keeps track of the humongous regions.
 159   HeapRegionSet _humongous_set;
 160 
 161   void eagerly_reclaim_humongous_regions();
 162   // Start a new incremental collection set for the next pause.
 163   void start_new_collection_set();
 164 
 165   // The number of regions we could create by expansion.
 166   uint _expansion_regions;
 167 
 168   // The block offset table for the G1 heap.
 169   G1BlockOffsetTable* _bot;
 170 
 171   // Tears down the region sets / lists so that they are empty and the
 172   // regions on the heap do not belong to a region set / list. The
 173   // only exception is the humongous set which we leave unaltered. If
 174   // free_list_only is true, it will only tear down the master free
 175   // list. It is called before a Full GC (free_list_only == false) or
 176   // before heap shrinking (free_list_only == true).
 177   void tear_down_region_sets(bool free_list_only);
 178 
 179   // Rebuilds the region sets / lists so that they are repopulated to
 180   // reflect the contents of the heap. The only exception is the
 181   // humongous set which was not torn down in the first place. If
 182   // free_list_only is true, it will only rebuild the master free
 183   // list. It is called after a Full GC (free_list_only == false) or