42   int64_t _previous_start_nanos;

    42   int64_t _previous_start_nanos;

    43   int64_t _last_update_nanos;

    43   int64_t _last_update_nanos;

    44   int64_t _last_checkpoint_offset;

    44   int64_t _last_checkpoint_offset;

    45   int64_t _last_metadata_offset;

    45   int64_t _last_metadata_offset;

    46   mutable u1 _generation;

    46   mutable u1 _generation;

    47 

    48 

    48   JfrChunk();

    49   JfrChunk();

    49   ~JfrChunk();

    50   ~JfrChunk();

    50   void reset();

    51   void reset();

    51 

    52 

    52   const char* magic() const;

    53   const char* magic() const;

    53   u2 major_version() const;

    54   u2 major_version() const;

    54   u2 minor_version() const;

    55   u2 minor_version() const;

    55   int64_t cpu_frequency() const;

    56   int64_t cpu_frequency() const;

    57 

    60 

    58   void update_start_ticks();

    61   void update_start_ticks();

    59   void update_start_nanos();

    62   void update_start_nanos();

    60   void save_current_and_update_start_ticks();

    63   void save_current_and_update_start_ticks();

    61   void save_current_and_update_start_nanos();

    64   void save_current_and_update_start_nanos();