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_COLLECTIONSETCHOOSER_HPP
26 #define SHARE_GC_G1_COLLECTIONSETCHOOSER_HPP
27
28 #include "gc/g1/heapRegion.hpp"
29 #include "memory/allocation.hpp"
30 #include "runtime/globals.hpp"
31
32 class G1CollectionSetCandidates;
33 class WorkGang;
34
35 // Helper class to calculate collection set candidates, and containing some related
36 // methods.
37 class CollectionSetChooser : public AllStatic {
38 static uint calculate_work_chunk_size(uint num_workers, uint num_regions);
39 public:
40 CollectionSetChooser();
41
42 static size_t mixed_gc_live_threshold_bytes() {
43 return HeapRegion::GrainBytes * (size_t) G1MixedGCLiveThresholdPercent / 100;
44 }
45
46 static bool region_occupancy_low_enough_for_evac(size_t live_bytes) {
47 return live_bytes < mixed_gc_live_threshold_bytes();
48 }
49
50 // Determine whether to add the given region to the collection set candidates or
51 // not. Currently, we skip pinned regions and regions whose live
52 // bytes are over the threshold. Humongous regions may be reclaimed during cleanup.
53 // Regions also need a complete remembered set to be a candidate.
54 static bool should_add(HeapRegion* hr);
55
56 // Build and return set of collection set candidates sorted by decreasing gc
57 // efficiency.
58 static G1CollectionSetCandidates* build(WorkGang* workers, uint max_num_regions);
59 };
60
61 #endif // SHARE_GC_G1_COLLECTIONSETCHOOSER_HPP
|
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_G1COLLECTIONSETCHOOSER_HPP
26 #define SHARE_GC_G1_G1COLLECTIONSETCHOOSER_HPP
27
28 #include "gc/g1/heapRegion.hpp"
29 #include "memory/allocation.hpp"
30 #include "runtime/globals.hpp"
31
32 class G1CollectionSetCandidates;
33 class WorkGang;
34
35 // Helper class to calculate collection set candidates, and containing some related
36 // methods.
37 class G1CollectionSetChooser : public AllStatic {
38 static uint calculate_work_chunk_size(uint num_workers, uint num_regions);
39 public:
40 G1CollectionSetChooser();
41
42 static size_t mixed_gc_live_threshold_bytes() {
43 return HeapRegion::GrainBytes * (size_t) G1MixedGCLiveThresholdPercent / 100;
44 }
45
46 static bool region_occupancy_low_enough_for_evac(size_t live_bytes) {
47 return live_bytes < mixed_gc_live_threshold_bytes();
48 }
49
50 // Determine whether to add the given region to the collection set candidates or
51 // not. Currently, we skip pinned regions and regions whose live
52 // bytes are over the threshold. Humongous regions may be reclaimed during cleanup.
53 // Regions also need a complete remembered set to be a candidate.
54 static bool should_add(HeapRegion* hr);
55
56 // Build and return set of collection set candidates sorted by decreasing gc
57 // efficiency.
58 static G1CollectionSetCandidates* build(WorkGang* workers, uint max_num_regions);
59 };
60
61 #endif // SHARE_GC_G1_G1COLLECTIONSETCHOOSER_HPP
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