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

*** 51,102 ****
        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> {
  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 _last_cycle_end;
  
    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:
--- 51,99 ----
        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;
  
    bool _update_refs_early;
    bool _update_refs_adaptive;
  
    RegionData* _region_data;
    size_t _region_data_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);
  
    RegionData* get_region_data_cache(size_t num);
  
    virtual void choose_collection_set_from_regiondata(ShenandoahCollectionSet* set,
                                                       RegionData* data, size_t data_size,
                                                       size_t free) = 0;
  
  public:
*** 112,129 ****
  
    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_update_refs();
  
-   virtual bool update_refs() const;
- 
    virtual bool should_degenerate_cycle();
  
    virtual void record_success_concurrent();
  
    virtual void record_success_degenerated();
--- 109,122 ----
  
    virtual void record_cycle_end();
  
    virtual void record_phase_time(ShenandoahPhaseTimings::Phase phase, double secs);
  
!   virtual bool should_start_normal_gc() const;
  
    virtual bool should_start_update_refs();
  
    virtual bool should_degenerate_cycle();
  
    virtual void record_success_concurrent();
  
    virtual void record_success_degenerated();
*** 132,143 ****
  
    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() {
    }
  
--- 125,134 ----