jdk-24/hotspot/src/share/vm/memory/tenuredGeneration.hpp

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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#ifndef SHARE_VM_MEMORY_TENUREDGENERATION_HPP
#define SHARE_VM_MEMORY_TENUREDGENERATION_HPP

#include "gc_implementation/shared/cSpaceCounters.hpp"
#include "gc_implementation/shared/gcStats.hpp"
#include "gc_implementation/shared/generationCounters.hpp"
#include "memory/generation.hpp"
#include "utilities/macros.hpp"

// TenuredGeneration models the heap containing old (promoted/tenured) objects.

class TenuredGeneration: public OneContigSpaceCardGeneration {
  friend class VMStructs;
 protected:
  GenerationCounters*   _gen_counters;
  CSpaceCounters*       _space_counters;

 public:
  TenuredGeneration(ReservedSpace rs, size_t initial_byte_size, int level,
                    GenRemSet* remset);

  Generation::Name kind() { return Generation::MarkSweepCompact; }

  // Printing
  const char* name() const { return "tenured generation"; }
  const char* short_name() const { return "Tenured"; }

  // Does a "full" (forced) collection invoked on this generation collect
  // all younger generations as well? Note that this is a
  // hack to allow the collection of the younger gen first if the flag is
  // set.
  virtual bool full_collects_younger_generations() const {
    return !ScavengeBeforeFullGC;
  }

  virtual void gc_prologue(bool full);
  bool should_collect(bool   full,
                      size_t word_size,
                      bool   is_tlab);

  virtual void compute_new_size();

  // Performance Counter support
  void update_counters();

  // Statistics

  virtual void update_gc_stats(int level, bool full);

  virtual bool promotion_attempt_is_safe(size_t max_promoted_in_bytes) const;
};

#endif // SHARE_VM_MEMORY_TENUREDGENERATION_HPP