1 /*
2 * Copyright (c) 1997, 2017, 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 #include "precompiled.hpp"
26 #include "jvm.h"
27 #include "gc/shared/ageTable.inline.hpp"
28 #include "gc/shared/ageTableTracer.hpp"
29 #include "gc/shared/collectedHeap.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "logging/log.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "utilities/copy.hpp"
34
35 /* Copyright (c) 1992, 2016, Oracle and/or its affiliates, and Stanford University.
36 See the LICENSE file for license information. */
37
AgeTable(bool global)38 AgeTable::AgeTable(bool global) {
39
40 clear();
41
42 if (UsePerfData && global) {
43
44 ResourceMark rm;
45 EXCEPTION_MARK;
46
47 const char* agetable_ns = "generation.0.agetable";
48 const char* bytes_ns = PerfDataManager::name_space(agetable_ns, "bytes");
49
50 for(int age = 0; age < table_size; age ++) {
51 char age_name[10];
52 jio_snprintf(age_name, sizeof(age_name), "%2.2d", age);
53 const char* cname = PerfDataManager::counter_name(bytes_ns, age_name);
54 _perf_sizes[age] = PerfDataManager::create_variable(SUN_GC, cname,
55 PerfData::U_Bytes,
56 CHECK);
57 }
58
59 const char* cname = PerfDataManager::counter_name(agetable_ns, "size");
60 PerfDataManager::create_constant(SUN_GC, cname, PerfData::U_None,
61 table_size, CHECK);
62 }
63 }
64
clear()65 void AgeTable::clear() {
66 for (size_t* p = sizes; p < sizes + table_size; ++p) {
67 *p = 0;
68 }
69 }
70
merge(AgeTable * subTable)71 void AgeTable::merge(AgeTable* subTable) {
72 for (int i = 0; i < table_size; i++) {
73 sizes[i]+= subTable->sizes[i];
74 }
75 }
76
compute_tenuring_threshold(size_t desired_survivor_size)77 uint AgeTable::compute_tenuring_threshold(size_t desired_survivor_size) {
78 uint result;
79
80 if (AlwaysTenure || NeverTenure) {
81 assert(MaxTenuringThreshold == 0 || MaxTenuringThreshold == markWord::max_age + 1,
82 "MaxTenuringThreshold should be 0 or markWord::max_age + 1, but is " UINTX_FORMAT, MaxTenuringThreshold);
83 result = MaxTenuringThreshold;
84 } else {
85 size_t total = 0;
86 uint age = 1;
87 assert(sizes[0] == 0, "no objects with age zero should be recorded");
88 while (age < table_size) {
89 total += sizes[age];
90 // check if including objects of age 'age' made us pass the desired
91 // size, if so 'age' is the new threshold
92 if (total > desired_survivor_size) break;
93 age++;
94 }
95 result = age < MaxTenuringThreshold ? age : MaxTenuringThreshold;
96 }
97
98
99 log_debug(gc, age)("Desired survivor size " SIZE_FORMAT " bytes, new threshold " UINTX_FORMAT " (max threshold " UINTX_FORMAT ")",
100 desired_survivor_size * oopSize, (uintx) result, MaxTenuringThreshold);
101
102 return result;
103 }
104
print_age_table(uint tenuring_threshold)105 void AgeTable::print_age_table(uint tenuring_threshold) {
106 if (log_is_enabled(Trace, gc, age) || UsePerfData || AgeTableTracer::is_tenuring_distribution_event_enabled()) {
107 log_trace(gc, age)("Age table with threshold %u (max threshold " UINTX_FORMAT ")",
108 tenuring_threshold, MaxTenuringThreshold);
109
110 size_t total = 0;
111 uint age = 1;
112 while (age < table_size) {
113 size_t wordSize = sizes[age];
114 total += wordSize;
115 if (wordSize > 0) {
116 log_trace(gc, age)("- age %3u: " SIZE_FORMAT_W(10) " bytes, " SIZE_FORMAT_W(10) " total",
117 age, wordSize * oopSize, total * oopSize);
118 }
119 AgeTableTracer::send_tenuring_distribution_event(age, wordSize * oopSize);
120 if (UsePerfData) {
121 _perf_sizes[age]->set_value(wordSize * oopSize);
122 }
123 age++;
124 }
125 }
126 }
127
128