22  * questions.
  23  *
  24  */
  25 
  26 #ifndef RUNTIME_THREADHEAPSAMPLER_HPP
  27 #define RUNTIME_THREADHEAPSAMPLER_HPP
  28 
  29 #include "memory/allocation.hpp"
  30 
  31 class ThreadHeapSampler {
  32  private:
  33   size_t _bytes_until_sample;
  34   // Cheap random number generator
  35   static uint64_t _rnd;
  36 
  37   void pick_next_geometric_sample();
  38   void pick_next_sample(size_t overflowed_bytes = 0);
  39   static int _enabled;
  40   static int _sampling_interval;
  41 
  42   // Used for assertion mode to determine if there is a path to a TLAB slow path
  43   // without a collector present.
  44   size_t _collectors_present;
  45 
  46   static void init_log_table();
  47 
  48  public:
  49   ThreadHeapSampler() : _bytes_until_sample(0) {
  50     _rnd = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(this));
  51     if (_rnd == 0) {
  52       _rnd = 1;
  53     }
  54 
  55     _collectors_present = 0;
  56   }
  57 
  58   size_t bytes_until_sample()                    { return _bytes_until_sample;   }
  59   void set_bytes_until_sample(size_t bytes)      { _bytes_until_sample = bytes;  }
  60 
  61   void check_for_sampling(oop obj, size_t size_in_bytes, size_t bytes_allocated_before);
  62 
  63   static int enabled();
  64   static void enable();
  65   static void disable();
  66 
  67   static void set_sampling_interval(int sampling_interval);
  68   static int get_sampling_interval();
  69 };
  70 
  71 #endif // SHARE_RUNTIME_THREADHEAPSAMPLER_HPP

  22  * questions.
  23  *
  24  */
  25 
  26 #ifndef RUNTIME_THREADHEAPSAMPLER_HPP
  27 #define RUNTIME_THREADHEAPSAMPLER_HPP
  28 
  29 #include "memory/allocation.hpp"
  30 
  31 class ThreadHeapSampler {
  32  private:
  33   size_t _bytes_until_sample;
  34   // Cheap random number generator
  35   static uint64_t _rnd;
  36 
  37   void pick_next_geometric_sample();
  38   void pick_next_sample(size_t overflowed_bytes = 0);
  39   static int _enabled;
  40   static int _sampling_interval;
  41 




  42   static void init_log_table();
  43 
  44  public:
  45   ThreadHeapSampler() : _bytes_until_sample(0) {
  46     _rnd = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(this));
  47     if (_rnd == 0) {
  48       _rnd = 1;
  49     }


  50   }
  51 
  52   size_t bytes_until_sample()                    { return _bytes_until_sample;   }
  53   void set_bytes_until_sample(size_t bytes)      { _bytes_until_sample = bytes;  }
  54 
  55   void check_for_sampling(oop obj, size_t size_in_bytes, size_t bytes_allocated_before);
  56 
  57   static int enabled();
  58   static void enable();
  59   static void disable();
  60 
  61   static void set_sampling_interval(int sampling_interval);
  62   static int get_sampling_interval();
  63 };
  64 
  65 #endif // SHARE_RUNTIME_THREADHEAPSAMPLER_HPP