1 /*
 2  * Copyright Amazon.com Inc. 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
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24 
25 #ifndef SHARE_GC_SHENANDOAH_HEURISTICS_SHENANDOAHGENERATIONALHEURISTICS_HPP
26 #define SHARE_GC_SHENANDOAH_HEURISTICS_SHENANDOAHGENERATIONALHEURISTICS_HPP
27 
28 
29 #include "gc/shenandoah/heuristics/shenandoahAdaptiveHeuristics.hpp"
30 
31 class ShenandoahGeneration;
32 
33 /*
34  * This class serves as the base class for heuristics used to trigger and
35  * choose the collection sets for young and global collections. It leans
36  * heavily on the existing functionality of ShenandoahAdaptiveHeuristics.
37  *
38  * It differs from the base class primarily in that choosing the collection
39  * set is responsible for mixed collections and in-place promotions of tenured
40  * regions.
41  */
42 class ShenandoahGenerationalHeuristics : public ShenandoahAdaptiveHeuristics {
43 
44 public:
45   explicit ShenandoahGenerationalHeuristics(ShenandoahGeneration* generation);
46 
47   void choose_collection_set(ShenandoahCollectionSet* collection_set) override;
48 protected:
49   ShenandoahGeneration* _generation;
50 
51   size_t add_preselected_regions_to_collection_set(ShenandoahCollectionSet* cset,
52                                                    const RegionData* data,
53                                                    size_t size) const;
54 
55   void log_cset_composition(ShenandoahCollectionSet* cset) const;
56 };
57 
58 
59 #endif //SHARE_GC_SHENANDOAH_HEURISTICS_SHENANDOAHGENERATIONALHEURISTICS_HPP