src/hotspot/share/gc/g1/heapRegionBounds.hpp
author tschatzl
Wed, 18 Apr 2018 11:36:48 +0200
changeset 49803 14518ac8df87
parent 47216 71c04702a3d5
child 53244 9807daeb47c4
permissions -rw-r--r--
8178105: Switch mark bitmaps during Remark Reviewed-by: sjohanss, sangheki

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef SHARE_VM_GC_G1_HEAPREGIONBOUNDS_HPP
#define SHARE_VM_GC_G1_HEAPREGIONBOUNDS_HPP

#include "memory/allocation.hpp"

class HeapRegionBounds : public AllStatic {
private:
  // Minimum region size; we won't go lower than that.
  // We might want to decrease this in the future, to deal with small
  // heaps a bit more efficiently.
  static const size_t MIN_REGION_SIZE = 1024 * 1024;

  // Maximum region size; we don't go higher than that. There's a good
  // reason for having an upper bound. We don't want regions to get too
  // large, otherwise cleanup's effectiveness would decrease as there
  // will be fewer opportunities to find totally empty regions after
  // marking.
  static const size_t MAX_REGION_SIZE = 32 * 1024 * 1024;

  // The automatic region size calculation will try to have around this
  // many regions in the heap (based on the min heap size).
  static const size_t TARGET_REGION_NUMBER = 2048;

public:
  static inline size_t min_size();
  static inline size_t max_size();
  static inline size_t target_number();
};

#endif // SHARE_VM_GC_G1_HEAPREGIONBOUNDS_HPP