1/*
2 * Copyright (c) 2013, 2018, Red Hat, Inc. All rights reserved.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24#include "precompiled.hpp"
25#include "gc/shenandoah/shenandoahMemoryPool.hpp"
26
27ShenandoahMemoryPool::ShenandoahMemoryPool(ShenandoahHeap* heap) :
28 CollectedMemoryPool("Shenandoah",
29 heap->initial_capacity(),
30 heap->max_capacity(),
31 true /* support_usage_threshold */),
32 _heap(heap) {}
33
34MemoryUsage ShenandoahMemoryPool::get_memory_usage() {
35 size_t initial = initial_size();
36 size_t max = max_size();
37 size_t used = used_in_bytes();
38 size_t committed = _heap->committed();
39
40 // These asserts can never fail: max is stable, and all updates to other values never overflow max.
41 assert(initial <= max, "initial: " SIZE_FORMAT ", max: " SIZE_FORMAT, initial, max);
42 assert(used <= max, "used: " SIZE_FORMAT ", max: " SIZE_FORMAT, used, max);
43 assert(committed <= max, "committed: " SIZE_FORMAT ", max: " SIZE_FORMAT, committed, max);
44
45 // Committed and used are updated concurrently and independently. They can momentarily break
46 // the assert below, which would also fail in downstream code. To avoid that, adjust values
47 // to make sense under the race. See JDK-8207200.
48 committed = MAX2(used, committed);
49 assert(used <= committed, "used: " SIZE_FORMAT ", committed: " SIZE_FORMAT, used, committed);
50
51 return MemoryUsage(initial, used, committed, max);
52}
53