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 *

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 * published by the Free Software Foundation.

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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * accompanied this code).

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 * 2 along with this work; if not, write to the Free Software Foundation,

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// A Generation that does parallel young-gen collection extended

// for adaptive size policy.

// Division of generation into spaces

// done by DefNewGeneration::compute_space_boundaries()

//      +---------------+

//      | uncommitted   |

//      |---------------|

//      | ss0           |

//      |---------------|

//      | ss1           |

//      |---------------|

//      |               |

//      | eden          |

//      |               |

//      +---------------+       <-- low end of VirtualSpace

//

class ASParNewGeneration: public ParNewGeneration {

  size_t _min_gen_size;

  // Resize the generation based on the desired sizes of

  // the constituent spaces.

  bool resize_generation(size_t eden_size, size_t survivor_size);

  // Resize the spaces based on their desired sizes but

  // respecting the maximum size of the generation.

  void resize_spaces(size_t eden_size, size_t survivor_size);

  // Return the byte size remaining to the minimum generation size.

  size_t available_to_min_gen();

  // Return the byte size remaining to the live data in the generation.

  size_t available_to_live() const;

  // Return the byte size that the generation is allowed to shrink.

  size_t limit_gen_shrink(size_t bytes);

  // Reset the size of the spaces after a shrink of the generation.

  void reset_survivors_after_shrink();

  // Accessor

  VirtualSpace* virtual_space() { return &_virtual_space; }

  virtual void adjust_desired_tenuring_threshold();

 public:

  ASParNewGeneration(ReservedSpace rs,

                     size_t initial_byte_size,

                     size_t min_byte_size,

                     int level);

  virtual const char* short_name() const { return "ASParNew"; }

  virtual const char* name() const;

  virtual Generation::Name kind() { return ASParNew; }

  // Change the sizes of eden and the survivor spaces in

  // the generation.  The parameters are desired sizes

  // and are not guaranteed to be met.  For example, if

  // the total is larger than the generation.

  void resize(size_t eden_size, size_t survivor_size);

  virtual void compute_new_size();

  size_t max_gen_size()                 { return _reserved.byte_size(); }

  size_t min_gen_size() const           { return _min_gen_size; }

  // Space boundary invariant checker

  void space_invariants() PRODUCT_RETURN;

};