src/hotspot/share/memory/metaspace/metaspaceStatistics.hpp

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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * accompanied this code).
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#ifndef SHARE_MEMORY_METASPACE_METASPACESTATISTICS_HPP
#define SHARE_MEMORY_METASPACE_METASPACESTATISTICS_HPP

#include "memory/metaspace.hpp"             // for MetadataType enum
#include "memory/metaspace/chunklevel.hpp"
#include "utilities/globalDefinitions.hpp"

class outputStream;

namespace metaspace {

// Contains a number of data output structures:
//
// - cm_stats_t
// - clms_stats_t -> arena_stats_t -> in_use_chunk_stats_t
//
// used for the various XXXX::add_to_statistic() methods in MetaspaceArena, ClassLoaderMetaspace
//  and ChunkManager, respectively.

struct ChunkManagerStats {

  // How many chunks per level are checked in.
  int _num_chunks[chunklevel::NUM_CHUNK_LEVELS];

  // Size, in words, of the sum of all committed areas in this chunk manager, per level.
  size_t _committed_word_size[chunklevel::NUM_CHUNK_LEVELS];

  ChunkManagerStats() : _num_chunks(), _committed_word_size() {}

  void add(const ChunkManagerStats& other);

  // Returns total word size of all chunks in this manager.
  size_t total_word_size() const;

  // Returns total committed word size of all chunks in this manager.
  size_t total_committed_word_size() const;

  void print_on(outputStream* st, size_t scale) const;

  DEBUG_ONLY(void verify() const;)

};

// Contains statistics for one or multiple chunks in use.
struct InUseChunkStats {

  // Number of chunks
  int _num;

  // Note:
  // capacity = committed + uncommitted
  //            committed = used + free + waste

  // Capacity (total sum of all chunk sizes) in words.
  // May contain committed and uncommitted space.
  size_t _word_size;

  // Total committed area, in words.
  size_t _committed_words;

  // Total used area, in words.
  size_t _used_words;

  // Total free committed area, in words.
  size_t _free_words;

  // Total waste committed area, in words.
  size_t _waste_words;

  InUseChunkStats() :
    _num(0),
    _word_size(0),
    _committed_words(0),
    _used_words(0),
    _free_words(0),
    _waste_words(0)
  {}

  void add(const InUseChunkStats& other) {
    _num += other._num;
    _word_size += other._word_size;
    _committed_words += other._committed_words;
    _used_words += other._used_words;
    _free_words += other._free_words;
    _waste_words += other._waste_words;

  }

  void print_on(outputStream* st, size_t scale) const;

  DEBUG_ONLY(void verify() const;)

};

// Class containing statistics for one or more MetaspaceArena objects.
struct  ArenaStats {

  // chunk statistics by chunk level
  InUseChunkStats _stats[chunklevel::NUM_CHUNK_LEVELS];
  uintx _free_blocks_num;
  size_t _free_blocks_word_size;

  ArenaStats() :
    _stats(),
    _free_blocks_num(0),
    _free_blocks_word_size(0)
  {}

  void add(const ArenaStats& other);

  void print_on(outputStream* st, size_t scale = K,  bool detailed = true) const;

  InUseChunkStats totals() const;

  DEBUG_ONLY(void verify() const;)

};

// Statistics for one or multiple ClassLoaderMetaspace objects
struct ClmsStats {

  ArenaStats _arena_stats_nonclass;
  ArenaStats _arena_stats_class;

  ClmsStats() : _arena_stats_nonclass(), _arena_stats_class() {}

  void add(const ClmsStats& other) {
    _arena_stats_nonclass.add(other._arena_stats_nonclass);
    _arena_stats_class.add(other._arena_stats_class);
  }

  void print_on(outputStream* st, size_t scale, bool detailed) const;

  // Returns total statistics for both class and non-class metaspace
  ArenaStats totals() const;

  DEBUG_ONLY(void verify() const;)

};

} // namespace metaspace

#endif // SHARE_MEMORY_METASPACE_METASPACESTATISTICS_HPP