1/*
2 * Copyright (c) 2007, 2019, 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.
22 *
23 */
24
25#ifndef SHARE_GC_G1_G1MEMORYPOOL_HPP
26#define SHARE_GC_G1_G1MEMORYPOOL_HPP
27
28#include "gc/g1/g1MonitoringSupport.hpp"
29#include "services/memoryPool.hpp"
30#include "services/memoryUsage.hpp"
31
32// This file contains the three classes that represent the memory
33// pools of the G1 spaces: G1EdenPool, G1SurvivorPool, and
34// G1OldGenPool. In G1, unlike our other GCs, we do not have a
35// physical space for each of those spaces. Instead, we allocate
36// regions for all three spaces out of a single pool of regions (that
37// pool basically covers the entire heap). As a result, the eden,
38// survivor, and old gen are considered logical spaces in G1, as each
39// is a set of non-contiguous regions. This is also reflected in the
40// way we map them to memory pools here. The easiest way to have done
41// this would have been to map the entire G1 heap to a single memory
42// pool. However, it's helpful to show how large the eden and survivor
43// get, as this does affect the performance and behavior of G1. Which
44// is why we introduce the three memory pools implemented here.
45//
46// See comments in g1MonitoringSupport.hpp for additional details
47// on this model.
48//
49
50class G1CollectedHeap;
51
52// This class is shared by the three G1 memory pool classes
53// (G1EdenPool, G1SurvivorPool, G1OldGenPool).
54class G1MemoryPoolSuper : public CollectedMemoryPool {
55protected:
56 G1MonitoringSupport* _g1mm;
57
58 // Would only be called from subclasses.
59 G1MemoryPoolSuper(G1CollectedHeap* g1h,
60 const char* name,
61 size_t init_size,
62 size_t max_size,
63 bool support_usage_threshold);
64};
65
66// Memory pool that represents the G1 eden.
67class G1EdenPool : public G1MemoryPoolSuper {
68public:
69 G1EdenPool(G1CollectedHeap* g1h, size_t initial_size);
70
71 size_t used_in_bytes() { return _g1mm->eden_space_used(); }
72
73 MemoryUsage get_memory_usage();
74};
75
76// Memory pool that represents the G1 survivor.
77class G1SurvivorPool : public G1MemoryPoolSuper {
78public:
79 G1SurvivorPool(G1CollectedHeap* g1h, size_t initial_size);
80
81 size_t used_in_bytes() { return _g1mm->survivor_space_used(); }
82
83 MemoryUsage get_memory_usage();
84};
85
86// Memory pool that represents the G1 old gen.
87class G1OldGenPool : public G1MemoryPoolSuper {
88public:
89 G1OldGenPool(G1CollectedHeap* g1h, size_t initial_size, size_t max_size);
90
91 size_t used_in_bytes() { return _g1mm->old_gen_used(); }
92
93 MemoryUsage get_memory_usage();
94};
95
96#endif // SHARE_GC_G1_G1MEMORYPOOL_HPP
97