1 /*
2 * Copyright (c) 2018, 2019, 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/mutexLocker.hpp"
30 #include "runtime/os.hpp"
31 #include "utilities/align.hpp"
32 #include "utilities/debug.hpp"
33 #include "utilities/globalDefinitions.hpp"
34 #include "utilities/ostream.hpp"
35 #include "unittest.hpp"
36
37 #if 0
38
39 #define NUM_PARALLEL_METASPACES 50
40 #define MAX_PER_METASPACE_ALLOCATION_WORDSIZE (512 * K)
41
42 //#define DEBUG_VERBOSE true
43
44 #ifdef DEBUG_VERBOSE
45
46 struct chunkmanager_statistics_t {
47 int num_specialized_chunks;
48 int num_small_chunks;
49 int num_medium_chunks;
50 int num_humongous_chunks;
51 };
52
53 extern void test_metaspace_retrieve_chunkmanager_statistics(Metaspace::MetadataType mdType, chunkmanager_statistics_t* out);
54
55 static void print_chunkmanager_statistics(outputStream* st, Metaspace::MetadataType mdType) {
56 chunkmanager_statistics_t stat;
57 test_metaspace_retrieve_chunkmanager_statistics(mdType, &stat);
58 st->print_cr("free chunks: %d / %d / %d / %d", stat.num_specialized_chunks, stat.num_small_chunks,
59 stat.num_medium_chunks, stat.num_humongous_chunks);
60 }
61
62 #endif
63
64 struct chunk_geometry_t {
65 size_t specialized_chunk_word_size;
66 size_t small_chunk_word_size;
67 size_t medium_chunk_word_size;
68 };
69
70 extern void test_metaspace_retrieve_chunk_geometry(Metaspace::MetadataType mdType, chunk_geometry_t* out);
71
72
73 class MetaspaceAllocationTest : public ::testing::Test {
74 protected:
75
76 struct {
77 size_t allocated;
78 Mutex* lock;
79 ClassLoaderMetaspace* space;
80 bool is_empty() const { return allocated == 0; }
81 bool is_full() const { return allocated >= MAX_PER_METASPACE_ALLOCATION_WORDSIZE; }
82 } _spaces[NUM_PARALLEL_METASPACES];
83
84 chunk_geometry_t _chunk_geometry;
85
86 virtual void SetUp() {
87 ::memset(_spaces, 0, sizeof(_spaces));
88 test_metaspace_retrieve_chunk_geometry(Metaspace::NonClassType, &_chunk_geometry);
89 }
90
91 virtual void TearDown() {
92 for (int i = 0; i < NUM_PARALLEL_METASPACES; i ++) {
93 if (_spaces[i].space != NULL) {
94 delete _spaces[i].space;
95 delete _spaces[i].lock;
96 }
97 }
98 }
99
100 void create_space(int i) {
101 assert(i >= 0 && i < NUM_PARALLEL_METASPACES, "Sanity");
102 assert(_spaces[i].space == NULL && _spaces[i].allocated == 0, "Sanity");
103 if (_spaces[i].lock == NULL) {
104 _spaces[i].lock = new Mutex(Monitor::native, "gtest-MetaspaceAllocationTest-lock", false, Monitor::_safepoint_check_never);
105 ASSERT_TRUE(_spaces[i].lock != NULL);
106 }
107 // Let every ~10th space be an unsafe anonymous one to test different allocation patterns.
108 const Metaspace::MetaspaceType msType = (os::random() % 100 < 10) ?
109 Metaspace::UnsafeAnonymousMetaspaceType : Metaspace::StandardMetaspaceType;
110 {
111 // Pull lock during space creation, since this is what happens in the VM too
112 // (see ClassLoaderData::metaspace_non_null(), which we mimick here).
113 MutexLocker ml(_spaces[i].lock, Mutex::_no_safepoint_check_flag);
114 _spaces[i].space = new ClassLoaderMetaspace(_spaces[i].lock, msType);
115 }
116 _spaces[i].allocated = 0;
117 ASSERT_TRUE(_spaces[i].space != NULL);
118 }
119
120 // Returns the index of a random space where index is [0..metaspaces) and which is
121 // empty, non-empty or full.
122 // Returns -1 if no matching space exists.
123 enum fillgrade { fg_empty, fg_non_empty, fg_full };
124 int get_random_matching_space(int metaspaces, fillgrade fg) {
125 const int start_index = os::random() % metaspaces;
126 int i = start_index;
127 do {
128 if (fg == fg_empty && _spaces[i].is_empty()) {
129 return i;
130 } else if ((fg == fg_full && _spaces[i].is_full()) ||
131 (fg == fg_non_empty && !_spaces[i].is_full() && !_spaces[i].is_empty())) {
132 return i;
133 }
134 i ++;
135 if (i == metaspaces) {
136 i = 0;
137 }
138 } while (i != start_index);
139 return -1;
140 }
141
142 int get_random_emtpy_space(int metaspaces) { return get_random_matching_space(metaspaces, fg_empty); }
143 int get_random_non_emtpy_space(int metaspaces) { return get_random_matching_space(metaspaces, fg_non_empty); }
144 int get_random_full_space(int metaspaces) { return get_random_matching_space(metaspaces, fg_full); }
145
146 void do_test(Metaspace::MetadataType mdType, int metaspaces, int phases, int allocs_per_phase,
147 float probability_for_large_allocations // 0.0-1.0
148 ) {
149 // Alternate between breathing in (allocating n blocks for a random Metaspace) and
150 // breathing out (deleting a random Metaspace). The intent is to stress the coalescation
151 // and splitting of free chunks.
152 int phases_done = 0;
153 bool allocating = true;
154 while (phases_done < phases) {
155 bool force_switch = false;
156 if (allocating) {
157 // Allocate space from metaspace, with a preference for completely empty spaces. This
158 // should provide a good mixture of metaspaces in the virtual space.
159 int index = get_random_emtpy_space(metaspaces);
160 if (index == -1) {
161 index = get_random_non_emtpy_space(metaspaces);
162 }
163 if (index == -1) {
164 // All spaces are full, switch to freeing.
165 force_switch = true;
166 } else {
167 // create space if it does not yet exist.
168 if (_spaces[index].space == NULL) {
169 create_space(index);
170 }
171 // Allocate a bunch of blocks from it. Mostly small stuff but mix in large allocations
172 // to force humongous chunk allocations.
173 int allocs_done = 0;
174 while (allocs_done < allocs_per_phase && !_spaces[index].is_full()) {
175 size_t size = 0;
176 int r = os::random() % 1000;
177 if ((float)r < probability_for_large_allocations * 1000.0) {
178 size = (os::random() % _chunk_geometry.medium_chunk_word_size) + _chunk_geometry.medium_chunk_word_size;
179 } else {
180 size = os::random() % 64;
181 }
182 // Note: In contrast to space creation, no need to lock here. ClassLoaderMetaspace::allocate() will lock itself.
183 MetaWord* const p = _spaces[index].space->allocate(size, mdType);
184 if (p == NULL) {
185 // We very probably did hit the metaspace "until-gc" limit.
186 #ifdef DEBUG_VERBOSE
187 tty->print_cr("OOM for " SIZE_FORMAT " words. ", size);
188 #endif
189 // Just switch to deallocation and resume tests.
190 force_switch = true;
191 break;
192 } else {
193 _spaces[index].allocated += size;
194 allocs_done ++;
195 }
196 }
197 }
198 } else {
199 // freeing: find a metaspace and delete it, with preference for completely filled spaces.
200 int index = get_random_full_space(metaspaces);
201 if (index == -1) {
202 index = get_random_non_emtpy_space(metaspaces);
203 }
204 if (index == -1) {
205 force_switch = true;
206 } else {
207 assert(_spaces[index].space != NULL && _spaces[index].allocated > 0, "Sanity");
208 // Note: do not lock here. In the "wild" (the VM), we do not so either (see ~ClassLoaderData()).
209 delete _spaces[index].space;
210 _spaces[index].space = NULL;
211 _spaces[index].allocated = 0;
212 }
213 }
214
215 if (force_switch) {
216 allocating = !allocating;
217 } else {
218 // periodically switch between allocating and freeing, but prefer allocation because
219 // we want to intermingle allocations of multiple metaspaces.
220 allocating = os::random() % 5 < 4;
221 }
222 phases_done ++;
223 #ifdef DEBUG_VERBOSE
224 int metaspaces_in_use = 0;
225 size_t total_allocated = 0;
226 for (int i = 0; i < metaspaces; i ++) {
227 if (_spaces[i].allocated > 0) {
228 total_allocated += _spaces[i].allocated;
229 metaspaces_in_use ++;
230 }
231 }
232 tty->print("%u:\tspaces: %d total words: " SIZE_FORMAT "\t\t\t", phases_done, metaspaces_in_use, total_allocated);
233 print_chunkmanager_statistics(tty, mdType);
234 #endif
235 }
236 #ifdef DEBUG_VERBOSE
237 tty->print_cr("Test finished. ");
238 MetaspaceUtils::print_metaspace_map(tty, mdType);
239 print_chunkmanager_statistics(tty, mdType);
240 #endif
241 }
242 };
243
244
245
246 TEST_F(MetaspaceAllocationTest, chunk_geometry) {
247 ASSERT_GT(_chunk_geometry.specialized_chunk_word_size, (size_t) 0);
248 ASSERT_GT(_chunk_geometry.small_chunk_word_size, _chunk_geometry.specialized_chunk_word_size);
249 ASSERT_EQ(_chunk_geometry.small_chunk_word_size % _chunk_geometry.specialized_chunk_word_size, (size_t)0);
250 ASSERT_GT(_chunk_geometry.medium_chunk_word_size, _chunk_geometry.small_chunk_word_size);
251 ASSERT_EQ(_chunk_geometry.medium_chunk_word_size % _chunk_geometry.small_chunk_word_size, (size_t)0);
252 }
253
254
255 TEST_VM_F(MetaspaceAllocationTest, single_space_nonclass) {
256 do_test(Metaspace::NonClassType, 1, 1000, 100, 0);
257 }
258
259 TEST_VM_F(MetaspaceAllocationTest, single_space_class) {
260 do_test(Metaspace::ClassType, 1, 1000, 100, 0);
261 }
262
263 TEST_VM_F(MetaspaceAllocationTest, multi_space_nonclass) {
264 do_test(Metaspace::NonClassType, NUM_PARALLEL_METASPACES, 100, 1000, 0.0);
265 }
266
267 TEST_VM_F(MetaspaceAllocationTest, multi_space_class) {
268 do_test(Metaspace::ClassType, NUM_PARALLEL_METASPACES, 100, 1000, 0.0);
269 }
270
271 TEST_VM_F(MetaspaceAllocationTest, multi_space_nonclass_2) {
272 // many metaspaces, with humongous chunks mixed in.
273 do_test(Metaspace::NonClassType, NUM_PARALLEL_METASPACES, 100, 1000, .006f);
274 }
275
276 #endif