1 /*
2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2018, SAP.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 #include "precompiled.hpp"
26 #include "memory/allocation.inline.hpp"
27 #include "memory/metaspace.hpp"
28 #include "runtime/mutex.hpp"
29 #include "runtime/os.hpp"
30 #include "utilities/align.hpp"
31 #include "utilities/debug.hpp"
32 #include "utilities/globalDefinitions.hpp"
33 #include "utilities/ostream.hpp"
34 #include "unittest.hpp"
35
36 #define NUM_PARALLEL_METASPACES 50
37 #define MAX_PER_METASPACE_ALLOCATION_WORDSIZE (512 * K)
38
39 //#define DEBUG_VERBOSE true
40
41 #ifdef DEBUG_VERBOSE
42
43 struct chunkmanager_statistics_t {
44 int num_specialized_chunks;
45 int num_small_chunks;
46 int num_medium_chunks;
47 int num_humongous_chunks;
48 };
49
50 extern void test_metaspace_retrieve_chunkmanager_statistics(Metaspace::MetadataType mdType, chunkmanager_statistics_t* out);
51
52 static void print_chunkmanager_statistics(outputStream* st, Metaspace::MetadataType mdType) {
53 chunkmanager_statistics_t stat;
54 test_metaspace_retrieve_chunkmanager_statistics(mdType, &stat);
55 st->print_cr("free chunks: %d / %d / %d / %d", stat.num_specialized_chunks, stat.num_small_chunks,
56 stat.num_medium_chunks, stat.num_humongous_chunks);
57 }
58
59 #endif
60
61 struct chunk_geometry_t {
62 size_t specialized_chunk_word_size;
63 size_t small_chunk_word_size;
64 size_t medium_chunk_word_size;
65 };
66
67 extern void test_metaspace_retrieve_chunk_geometry(Metaspace::MetadataType mdType, chunk_geometry_t* out);
68
69
70 class MetaspaceAllocationTest : public ::testing::Test {
71 protected:
72
73 struct {
74 size_t allocated;
75 Mutex* lock;
76 ClassLoaderMetaspace* space;
77 bool is_empty() const { return allocated == 0; }
78 bool is_full() const { return allocated >= MAX_PER_METASPACE_ALLOCATION_WORDSIZE; }
79 } _spaces[NUM_PARALLEL_METASPACES];
80
81 chunk_geometry_t _chunk_geometry;
82
83 virtual void SetUp() {
84 ::memset(_spaces, 0, sizeof(_spaces));
85 test_metaspace_retrieve_chunk_geometry(Metaspace::NonClassType, &_chunk_geometry);
86 }
87
88 virtual void TearDown() {
89 for (int i = 0; i < NUM_PARALLEL_METASPACES; i ++) {
90 if (_spaces[i].space != NULL) {
91 delete _spaces[i].space;
92 delete _spaces[i].lock;
93 }
94 }
95 }
96
97 void create_space(int i) {
98 assert(i >= 0 && i < NUM_PARALLEL_METASPACES, "Sanity");
99 assert(_spaces[i].space == NULL && _spaces[i].allocated == 0, "Sanity");
100 if (_spaces[i].lock == NULL) {
101 _spaces[i].lock = new Mutex(Monitor::native, "gtest-MetaspaceAllocationTest-lock", false, Monitor::_safepoint_check_never);
102 ASSERT_TRUE(_spaces[i].lock != NULL);
103 }
104 // Let every ~10th space be an anonymous one to test different allocation patterns.
105 const Metaspace::MetaspaceType msType = (os::random() % 100 < 10) ?
106 Metaspace::AnonymousMetaspaceType : Metaspace::StandardMetaspaceType;
107 _spaces[i].space = new ClassLoaderMetaspace(_spaces[i].lock, msType);
108 _spaces[i].allocated = 0;
109 ASSERT_TRUE(_spaces[i].space != NULL);
110 }
111
112 // Returns the index of a random space where index is [0..metaspaces) and which is
113 // empty, non-empty or full.
114 // Returns -1 if no matching space exists.
115 enum fillgrade { fg_empty, fg_non_empty, fg_full };
116 int get_random_matching_space(int metaspaces, fillgrade fg) {
117 const int start_index = os::random() % metaspaces;
118 int i = start_index;
119 do {
120 if (fg == fg_empty && _spaces[i].is_empty()) {
121 return i;
122 } else if ((fg == fg_full && _spaces[i].is_full()) ||
123 (fg == fg_non_empty && !_spaces[i].is_full() && !_spaces[i].is_empty())) {
124 return i;
125 }
126 i ++;
127 if (i == metaspaces) {
128 i = 0;
129 }
130 } while (i != start_index);
131 return -1;
132 }
133
134 int get_random_emtpy_space(int metaspaces) { return get_random_matching_space(metaspaces, fg_empty); }
135 int get_random_non_emtpy_space(int metaspaces) { return get_random_matching_space(metaspaces, fg_non_empty); }
136 int get_random_full_space(int metaspaces) { return get_random_matching_space(metaspaces, fg_full); }
137
138 void do_test(Metaspace::MetadataType mdType, int metaspaces, int phases, int allocs_per_phase,
139 float probability_for_large_allocations // 0.0-1.0
140 ) {
141 // Alternate between breathing in (allocating n blocks for a random Metaspace) and
142 // breathing out (deleting a random Metaspace). The intent is to stress the coalescation
143 // and splitting of free chunks.
144 int phases_done = 0;
145 bool allocating = true;
146 while (phases_done < phases) {
147 bool force_switch = false;
148 if (allocating) {
149 // Allocate space from metaspace, with a preference for completely empty spaces. This
150 // should provide a good mixture of metaspaces in the virtual space.
151 int index = get_random_emtpy_space(metaspaces);
152 if (index == -1) {
153 index = get_random_non_emtpy_space(metaspaces);
154 }
155 if (index == -1) {
156 // All spaces are full, switch to freeing.
157 force_switch = true;
158 } else {
159 // create space if it does not yet exist.
160 if (_spaces[index].space == NULL) {
161 create_space(index);
162 }
163 // Allocate a bunch of blocks from it. Mostly small stuff but mix in large allocations
164 // to force humongous chunk allocations.
165 int allocs_done = 0;
166 while (allocs_done < allocs_per_phase && !_spaces[index].is_full()) {
167 size_t size = 0;
168 int r = os::random() % 1000;
169 if ((float)r < probability_for_large_allocations * 1000.0) {
170 size = (os::random() % _chunk_geometry.medium_chunk_word_size) + _chunk_geometry.medium_chunk_word_size;
171 } else {
172 size = os::random() % 64;
173 }
174 MetaWord* const p = _spaces[index].space->allocate(size, mdType);
175 if (p == NULL) {
176 // We very probably did hit the metaspace "until-gc" limit.
177 #ifdef DEBUG_VERBOSE
178 tty->print_cr("OOM for " SIZE_FORMAT " words. ", size);
179 #endif
180 // Just switch to deallocation and resume tests.
181 force_switch = true;
182 break;
183 } else {
184 _spaces[index].allocated += size;
185 allocs_done ++;
186 }
187 }
188 }
189 } else {
190 // freeing: find a metaspace and delete it, with preference for completely filled spaces.
191 int index = get_random_full_space(metaspaces);
192 if (index == -1) {
193 index = get_random_non_emtpy_space(metaspaces);
194 }
195 if (index == -1) {
196 force_switch = true;
197 } else {
198 assert(_spaces[index].space != NULL && _spaces[index].allocated > 0, "Sanity");
199 delete _spaces[index].space;
200 _spaces[index].space = NULL;
201 _spaces[index].allocated = 0;
202 }
203 }
204
205 if (force_switch) {
206 allocating = !allocating;
207 } else {
208 // periodically switch between allocating and freeing, but prefer allocation because
209 // we want to intermingle allocations of multiple metaspaces.
210 allocating = os::random() % 5 < 4;
211 }
212 phases_done ++;
213 #ifdef DEBUG_VERBOSE
214 int metaspaces_in_use = 0;
215 size_t total_allocated = 0;
216 for (int i = 0; i < metaspaces; i ++) {
217 if (_spaces[i].allocated > 0) {
218 total_allocated += _spaces[i].allocated;
219 metaspaces_in_use ++;
220 }
221 }
222 tty->print("%u:\tspaces: %d total words: " SIZE_FORMAT "\t\t\t", phases_done, metaspaces_in_use, total_allocated);
223 print_chunkmanager_statistics(tty, mdType);
224 #endif
225 }
226 #ifdef DEBUG_VERBOSE
227 tty->print_cr("Test finished. ");
228 MetaspaceUtils::print_metaspace_map(tty, mdType);
229 print_chunkmanager_statistics(tty, mdType);
230 #endif
231 }
232 };
233
234
235
236 TEST_F(MetaspaceAllocationTest, chunk_geometry) {
237 ASSERT_GT(_chunk_geometry.specialized_chunk_word_size, (size_t) 0);
238 ASSERT_GT(_chunk_geometry.small_chunk_word_size, _chunk_geometry.specialized_chunk_word_size);
239 ASSERT_EQ(_chunk_geometry.small_chunk_word_size % _chunk_geometry.specialized_chunk_word_size, (size_t)0);
240 ASSERT_GT(_chunk_geometry.medium_chunk_word_size, _chunk_geometry.small_chunk_word_size);
241 ASSERT_EQ(_chunk_geometry.medium_chunk_word_size % _chunk_geometry.small_chunk_word_size, (size_t)0);
242 }
243
244
245 TEST_VM_F(MetaspaceAllocationTest, single_space_nonclass) {
246 do_test(Metaspace::NonClassType, 1, 1000, 100, 0);
247 }
248
249 TEST_VM_F(MetaspaceAllocationTest, single_space_class) {
250 do_test(Metaspace::ClassType, 1, 1000, 100, 0);
251 }
252
253 TEST_VM_F(MetaspaceAllocationTest, multi_space_nonclass) {
254 do_test(Metaspace::NonClassType, NUM_PARALLEL_METASPACES, 100, 1000, 0.0);
255 }
256
257 TEST_VM_F(MetaspaceAllocationTest, multi_space_class) {
258 do_test(Metaspace::ClassType, NUM_PARALLEL_METASPACES, 100, 1000, 0.0);
259 }
260
261 TEST_VM_F(MetaspaceAllocationTest, multi_space_nonclass_2) {
262 // many metaspaces, with humongous chunks mixed in.
263 do_test(Metaspace::NonClassType, NUM_PARALLEL_METASPACES, 100, 1000, .006f);
264 }
265