src/share/vm/gc_implementation/shenandoah/shenandoahHeuristics.hpp

rev 10533 : [backport] Replace risky SBS::need_update_refs_barrier with straightforward check
rev 10584 : [backport] Move periodic GC decision making to GC heuristics base class
rev 10606 : [backport] Adaptive/Traversal heuristics rewrite for allocation rate
rev 10607 : [backport] Remove ShHeuristics::print_threshold
rev 10637 : [backport] Purge partial heuristics and connection matrix infrastructure

@@ -51,52 +51,49 @@
       log_info(gc)("Heuristics ergonomically sets -XX:" #name "=" #value);  \
       FLAG_SET_DEFAULT(name, value);                                        \
     }                                                                       \
   } while (0)
 
-
 class ShenandoahCollectionSet;
 class ShenandoahHeapRegion;
 
 class ShenandoahHeuristics : public CHeapObj<mtGC> {
+  static const intx Concurrent_Adjust   =  1; // recover from penalties
+  static const intx Degenerated_Penalty = 10; // how much to penalize average GC duration history on Degenerated GC
+  static const intx Full_Penalty        = 20; // how much to penalize average GC duration history on Full GC
+
 protected:
   typedef struct {
     ShenandoahHeapRegion* _region;
     size_t _garbage;
     uint64_t _seqnum_last_alloc;
   } RegionData;
 
-  typedef struct {
-    ShenandoahHeapRegion* _region;
-    size_t _connections;
-  } RegionConnections;
-
   bool _update_refs_early;
   bool _update_refs_adaptive;
 
   RegionData* _region_data;
   size_t _region_data_size;
 
-  RegionConnections* _region_connects;
-  size_t _region_connects_size;
-
   uint _degenerated_cycles_in_a_row;
   uint _successful_cycles_in_a_row;
 
   size_t _bytes_in_cset;
 
+  double _cycle_start;
   double _last_cycle_end;
 
+  size_t _gc_times_learned;
+  size_t _gc_time_penalties;
+  TruncatedSeq* _gc_time_history;
+
   static int compare_by_garbage(RegionData a, RegionData b);
   static int compare_by_alloc_seq_ascending(RegionData a, RegionData b);
   static int compare_by_alloc_seq_descending(RegionData a, RegionData b);
-  static int compare_by_connects(RegionConnections a, RegionConnections b);
 
   RegionData* get_region_data_cache(size_t num);
 
-  RegionConnections* get_region_connects_cache(size_t num);
-
   virtual void choose_collection_set_from_regiondata(ShenandoahCollectionSet* set,
                                                      RegionData* data, size_t data_size,
                                                      size_t free) = 0;
 
 public:

@@ -112,18 +109,14 @@
 
   virtual void record_cycle_end();
 
   virtual void record_phase_time(ShenandoahPhaseTimings::Phase phase, double secs);
 
-  virtual void print_thresholds();
-
-  virtual bool should_start_normal_gc() const = 0;
+  virtual bool should_start_normal_gc() const;
 
   virtual bool should_start_update_refs();
 
-  virtual bool update_refs() const;
-
   virtual bool should_degenerate_cycle();
 
   virtual void record_success_concurrent();
 
   virtual void record_success_degenerated();

@@ -132,12 +125,10 @@
 
   virtual void record_allocation_failure_gc();
 
   virtual void record_explicit_gc();
 
-  virtual void record_peak_occupancy();
-
   virtual void start_choose_collection_set() {
   }
   virtual void end_choose_collection_set() {
   }