1 /*
2 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARNEW_ASPARNEWGENERATION_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_PARNEW_ASPARNEWGENERATION_HPP
27
28 #include "gc_implementation/parNew/parNewGeneration.hpp"
29 #include "gc_implementation/shared/adaptiveSizePolicy.hpp"
30
31 // A Generation that does parallel young-gen collection extended
32 // for adaptive size policy.
33
34 // Division of generation into spaces
35 // done by DefNewGeneration::compute_space_boundaries()
36 // +---------------+
37 // | uncommitted |
38 // |---------------|
39 // | ss0 |
40 // |---------------|
41 // | ss1 |
42 // |---------------|
43 // | |
44 // | eden |
45 // | |
46 // +---------------+ <-- low end of VirtualSpace
47 //
48 class ASParNewGeneration: public ParNewGeneration {
49
50 size_t _min_gen_size;
51
52 // Resize the generation based on the desired sizes of
53 // the constituent spaces.
54 bool resize_generation(size_t eden_size, size_t survivor_size);
55 // Resize the spaces based on their desired sizes but
56 // respecting the maximum size of the generation.
57 void resize_spaces(size_t eden_size, size_t survivor_size);
58 // Return the byte size remaining to the minimum generation size.
59 size_t available_to_min_gen();
60 // Return the byte size remaining to the live data in the generation.
61 size_t available_to_live() const;
62 // Return the byte size that the generation is allowed to shrink.
63 size_t limit_gen_shrink(size_t bytes);
64 // Reset the size of the spaces after a shrink of the generation.
65 void reset_survivors_after_shrink();
66
67 // Accessor
68 VirtualSpace* virtual_space() { return &_virtual_space; }
69
70 virtual void adjust_desired_tenuring_threshold();
71
72 public:
73
74 ASParNewGeneration(ReservedSpace rs,
75 size_t initial_byte_size,
76 size_t min_byte_size,
77 int level);
78
79 virtual const char* short_name() const { return "ASParNew"; }
80 virtual const char* name() const;
81 virtual Generation::Name kind() { return ASParNew; }
82
83 // Change the sizes of eden and the survivor spaces in
84 // the generation. The parameters are desired sizes
85 // and are not guaranteed to be met. For example, if
86 // the total is larger than the generation.
87 void resize(size_t eden_size, size_t survivor_size);
88
89 virtual void compute_new_size();
90
91 size_t max_gen_size() { return _reserved.byte_size(); }
92 size_t min_gen_size() const { return _min_gen_size; }
93
94 // Space boundary invariant checker
95 void space_invariants() PRODUCT_RETURN;
96 };
97
98 #endif // SHARE_VM_GC_IMPLEMENTATION_PARNEW_ASPARNEWGENERATION_HPP