src/share/vm/gc_implementation/parallelScavenge/adjoiningGenerations.hpp

changeset 0
f90c822e73f8
child 6876
710a3c8b516e
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/share/vm/gc_implementation/parallelScavenge/adjoiningGenerations.hpp	Wed Apr 27 01:25:04 2016 +0800
     1.3 @@ -0,0 +1,80 @@
     1.4 +/*
     1.5 + * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
     1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     1.7 + *
     1.8 + * This code is free software; you can redistribute it and/or modify it
     1.9 + * under the terms of the GNU General Public License version 2 only, as
    1.10 + * published by the Free Software Foundation.
    1.11 + *
    1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
    1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    1.14 + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    1.15 + * version 2 for more details (a copy is included in the LICENSE file that
    1.16 + * accompanied this code).
    1.17 + *
    1.18 + * You should have received a copy of the GNU General Public License version
    1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
    1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    1.21 + *
    1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    1.23 + * or visit www.oracle.com if you need additional information or have any
    1.24 + * questions.
    1.25 + *
    1.26 + */
    1.27 +
    1.28 +#ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_ADJOININGGENERATIONS_HPP
    1.29 +#define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_ADJOININGGENERATIONS_HPP
    1.30 +
    1.31 +#include "gc_implementation/parallelScavenge/adjoiningVirtualSpaces.hpp"
    1.32 +#include "gc_implementation/parallelScavenge/asPSOldGen.hpp"
    1.33 +#include "gc_implementation/parallelScavenge/asPSYoungGen.hpp"
    1.34 +#include "gc_implementation/parallelScavenge/generationSizer.hpp"
    1.35 +
    1.36 +
    1.37 +// Contains two generations that both use an AdjoiningVirtualSpaces.
    1.38 +// The two generations are adjacent in the reserved space for the
    1.39 +// heap.  Each generation has a virtual space and shrinking and
    1.40 +// expanding of the generations can still be down with that
    1.41 +// virtual space as was previously done.  If expanding of reserved
    1.42 +// size of a generation is required, the adjacent generation
    1.43 +// must be shrunk.  Adjusting the boundary between the generations
    1.44 +// is called for in this class.
    1.45 +
    1.46 +class AdjoiningGenerations : public CHeapObj<mtGC> {
    1.47 +  friend class VMStructs;
    1.48 + private:
    1.49 +  // The young generation and old generation, respectively
    1.50 +  PSYoungGen* _young_gen;
    1.51 +  PSOldGen* _old_gen;
    1.52 +
    1.53 +  // The spaces used by the two generations.
    1.54 +  AdjoiningVirtualSpaces _virtual_spaces;
    1.55 +
    1.56 +  // Move boundary up to expand old gen.  Checks are made to
    1.57 +  // determine if the move can be done with specified limits.
    1.58 +  void request_old_gen_expansion(size_t desired_change_in_bytes);
    1.59 +  // Move boundary down to expand young gen.
    1.60 +  bool request_young_gen_expansion(size_t desired_change_in_bytes);
    1.61 +
    1.62 + public:
    1.63 +  AdjoiningGenerations(ReservedSpace rs, GenerationSizer* policy, size_t alignment);
    1.64 +
    1.65 +  // Accessors
    1.66 +  PSYoungGen* young_gen() { return _young_gen; }
    1.67 +  PSOldGen* old_gen() { return _old_gen; }
    1.68 +
    1.69 +  AdjoiningVirtualSpaces* virtual_spaces() { return &_virtual_spaces; }
    1.70 +
    1.71 +  // Additional space is needed in the old generation.  Check
    1.72 +  // the available space and attempt to move the boundary if more space
    1.73 +  // is needed.  The growth is not guaranteed to occur.
    1.74 +  void adjust_boundary_for_old_gen_needs(size_t desired_change_in_bytes);
    1.75 +  // Similary for a growth of the young generation.
    1.76 +  void adjust_boundary_for_young_gen_needs(size_t eden_size, size_t survivor_size);
    1.77 +
    1.78 +  // Return the total byte size of the reserved space
    1.79 +  // for the adjoining generations.
    1.80 +  size_t reserved_byte_size();
    1.81 +};
    1.82 +
    1.83 +#endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_ADJOININGGENERATIONS_HPP

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