src/hotspot/share/memory/metaspaceStats.hpp

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#ifndef SHARE_MEMORY_METASPACESTATS_HPP
#define SHARE_MEMORY_METASPACESTATS_HPP

#include "utilities/globalDefinitions.hpp"

// Data holder classes for metaspace statistics.
//
// - MetaspaceStats: keeps reserved, committed and used byte counters;
//                   retrieve with MetaspaceUtils::get_statistics(MetadataType) for either class space
//                   or non-class space
//
// - MetaspaceCombinedStats: keeps reserved, committed and used byte counters, separately for both class- and non-class-space;
//                      retrieve with MetaspaceUtils::get_combined_statistics()

// (Note: just for NMT these objects need to be mutable)

class MetaspaceStats {
  size_t _reserved;
  size_t _committed;
  size_t _used;
public:
  MetaspaceStats() : _reserved(0), _committed(0), _used(0) {}
  MetaspaceStats(size_t r, size_t c, size_t u) : _reserved(r), _committed(c), _used(u) {}
  size_t used() const       { return _used; }
  size_t committed() const  { return _committed; }
  size_t reserved() const   { return _reserved; }
};

// Class holds combined statistics for both non-class and class space.
class MetaspaceCombinedStats : public MetaspaceStats {
  MetaspaceStats _cstats;  // class space stats
  MetaspaceStats _ncstats; // non-class space stats
public:
  MetaspaceCombinedStats() {}
  MetaspaceCombinedStats(const MetaspaceStats& cstats, const MetaspaceStats& ncstats) :
    MetaspaceStats(cstats.reserved() + ncstats.reserved(),
                   cstats.committed() + ncstats.committed(),
                   cstats.used() + ncstats.used()),
    _cstats(cstats), _ncstats(ncstats)
  {}

  const MetaspaceStats& class_space_stats() const { return _cstats; }
  const MetaspaceStats& non_class_space_stats() const { return _ncstats; }
  size_t class_used() const       { return _cstats.used(); }
  size_t class_committed() const  { return _cstats.committed(); }
  size_t class_reserved() const   { return _cstats.reserved(); }
  size_t non_class_used() const       { return _ncstats.used(); }
  size_t non_class_committed() const  { return _ncstats.committed(); }
  size_t non_class_reserved() const   { return _ncstats.reserved(); }
};

#endif // SHARE_MEMORY_METASPACESTATS_HPP