1 /*
2 * Copyright (c) 2014, 2018, 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 import java.lang.management.ManagementFactory;
25 import java.lang.management.MemoryPoolMXBean;
26 import java.util.Objects;
27 import java.util.Optional;
28 import java.util.regex.Matcher;
29 import java.util.regex.Pattern;
30
31 import jdk.test.lib.Asserts;
32 import com.sun.management.ThreadMXBean;
33 import sun.hotspot.WhiteBox;
34 import jdk.internal.misc.Unsafe;
35
36 /**
37 * Main class for tests on {@code SurvivorAlignmentInBytes} option.
38 *
39 * Typical usage is to obtain instance using fromArgs method, allocate objects
40 * and verify that actual memory usage in tested heap space is close to
41 * expected.
42 */
43 public class SurvivorAlignmentTestMain {
44 enum HeapSpace {
45 EDEN,
46 SURVIVOR,
47 TENURED
48 }
49
50 public static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();
51
52 public static final long MAX_TENURING_THRESHOLD = Optional.ofNullable(
53 SurvivorAlignmentTestMain.WHITE_BOX.getIntxVMFlag(
54 "MaxTenuringThreshold")).orElse(15L);
55
56 /**
57 * Regexp used to parse memory size params, like 2G, 34m or 15k.
58 */
59 private static final Pattern SIZE_REGEX
60 = Pattern.compile("(?<size>[0-9]+)(?<multiplier>[GMKgmk])?");
61
62 // Names of different heap spaces.
63 private static final String DEF_NEW_EDEN = "Eden Space";
64 private static final String DEF_NEW_SURVIVOR = "Survivor Space";
65 private static final String PAR_NEW_EDEN = "Par Eden Space";
66 private static final String PAR_NEW_SURVIVOR = "Par Survivor Space";
67 private static final String PS_EDEN = "PS Eden Space";
68 private static final String PS_SURVIVOR = "PS Survivor Space";
69 private static final String G1_EDEN = "G1 Eden Space";
70 private static final String G1_SURVIVOR = "G1 Survivor Space";
71 private static final String SERIAL_TENURED = "Tenured Gen";
72 private static final String CMS_TENURED = "CMS Old Gen";
73 private static final String PS_TENURED = "PS Old Gen";
74 private static final String G1_TENURED_LEGACY = "G1 Old Gen";
75 private static final String G1_TENURED = "G1 Old Space";
76
77 private static final long G1_HEAP_REGION_SIZE = Optional.ofNullable(
78 SurvivorAlignmentTestMain.WHITE_BOX.getUintxVMFlag(
79 "G1HeapRegionSize")).orElse(-1L);
80
81 /**
82 * Min size of free chunk in CMS generation.
83 * An object allocated in CMS generation will at least occupy this amount
84 * of bytes.
85 */
86 private static final long CMS_MIN_FREE_CHUNK_SIZE
87 = 3L * Unsafe.ADDRESS_SIZE;
88
89 private static final AlignmentHelper EDEN_SPACE_HELPER;
90 private static final AlignmentHelper SURVIVOR_SPACE_HELPER;
91 private static final AlignmentHelper TENURED_SPACE_HELPER;
92 /**
93 * Amount of memory that should be filled during a test run.
94 */
95 private final long memoryToFill;
96 /**
97 * The size of an objects that will be allocated during a test run.
98 */
99 private final long objectSize;
100 /**
101 * Amount of memory that will be actually occupied by an object in eden
102 * space.
103 */
104 private final long actualObjectSize;
105 /**
106 * Storage for allocated objects.
107 */
108 private final Object[] garbage;
109 /**
110 * Heap space whose memory usage is a subject of assertions during the test
111 * run.
112 */
113 private final HeapSpace testedSpace;
114
115 private long[] baselinedThreadMemoryUsage = null;
116 private long[] threadIds = null;
117
118 /**
119 * Initialize {@code EDEN_SPACE_HELPER}, {@code SURVIVOR_SPACE_HELPER} and
120 * {@code TENURED_SPACE_HELPER} to represent heap spaces in use.
121 *
122 * Note that regardless to GC object's alignment in survivor space is
123 * expected to be equal to {@code SurvivorAlignmentInBytes} value and
124 * alignment in other spaces is expected to be equal to
125 * {@code ObjectAlignmentInBytes} value.
126 *
127 * In CMS generation we can't allocate less then {@code MinFreeChunk} value,
128 * for other CGs we expect that object of size {@code MIN_OBJECT_SIZE}
129 * could be allocated as it is (of course, its size could be aligned
130 * according to alignment value used in a particular space).
131 *
132 * For G1 GC MXBeans could report memory usage only with region size
133 * precision (if an object allocated in some G1 heap region, then all region
134 * will claimed as used), so for G1's spaces precision is equal to
135 * {@code G1HeapRegionSize} value.
136 */
137 static {
138 AlignmentHelper edenHelper = null;
139 AlignmentHelper survivorHelper = null;
140 AlignmentHelper tenuredHelper = null;
141 for (MemoryPoolMXBean pool : ManagementFactory.getMemoryPoolMXBeans()) {
142 switch (pool.getName()) {
143 case SurvivorAlignmentTestMain.DEF_NEW_EDEN:
144 case SurvivorAlignmentTestMain.PAR_NEW_EDEN:
145 case SurvivorAlignmentTestMain.PS_EDEN:
146 Asserts.assertNull(edenHelper,
147 "Only one bean for eden space is expected.");
148 edenHelper = new AlignmentHelper(
149 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
150 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
151 AlignmentHelper.MIN_OBJECT_SIZE, pool);
152 break;
153 case SurvivorAlignmentTestMain.G1_EDEN:
154 Asserts.assertNull(edenHelper,
155 "Only one bean for eden space is expected.");
156 edenHelper = new AlignmentHelper(
157 SurvivorAlignmentTestMain.G1_HEAP_REGION_SIZE,
158 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
159 AlignmentHelper.MIN_OBJECT_SIZE, pool);
160 break;
161 case SurvivorAlignmentTestMain.DEF_NEW_SURVIVOR:
162 case SurvivorAlignmentTestMain.PAR_NEW_SURVIVOR:
163 case SurvivorAlignmentTestMain.PS_SURVIVOR:
164 Asserts.assertNull(survivorHelper,
165 "Only one bean for survivor space is expected.");
166 survivorHelper = new AlignmentHelper(
167 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
168 AlignmentHelper.SURVIVOR_ALIGNMENT_IN_BYTES,
169 AlignmentHelper.MIN_OBJECT_SIZE, pool);
170 break;
171 case SurvivorAlignmentTestMain.G1_SURVIVOR:
172 Asserts.assertNull(survivorHelper,
173 "Only one bean for survivor space is expected.");
174 survivorHelper = new AlignmentHelper(
175 SurvivorAlignmentTestMain.G1_HEAP_REGION_SIZE,
176 AlignmentHelper.SURVIVOR_ALIGNMENT_IN_BYTES,
177 AlignmentHelper.MIN_OBJECT_SIZE, pool);
178 break;
179 case SurvivorAlignmentTestMain.SERIAL_TENURED:
180 case SurvivorAlignmentTestMain.PS_TENURED:
181 case SurvivorAlignmentTestMain.G1_TENURED_LEGACY:
182 case SurvivorAlignmentTestMain.G1_TENURED:
183 Asserts.assertNull(tenuredHelper,
184 "Only one bean for tenured space is expected.");
185 tenuredHelper = new AlignmentHelper(
186 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
187 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
188 AlignmentHelper.MIN_OBJECT_SIZE, pool);
189 break;
190 case SurvivorAlignmentTestMain.CMS_TENURED:
191 Asserts.assertNull(tenuredHelper,
192 "Only one bean for tenured space is expected.");
193 tenuredHelper = new AlignmentHelper(
194 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
195 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
196 SurvivorAlignmentTestMain.CMS_MIN_FREE_CHUNK_SIZE,
197 pool);
198 break;
199 }
200 }
201 EDEN_SPACE_HELPER = Objects.requireNonNull(edenHelper,
202 "AlignmentHelper for eden space should be initialized.");
203 SURVIVOR_SPACE_HELPER = Objects.requireNonNull(survivorHelper,
204 "AlignmentHelper for survivor space should be initialized.");
205 TENURED_SPACE_HELPER = Objects.requireNonNull(tenuredHelper,
206 "AlignmentHelper for tenured space should be initialized.");
207 }
208 /**
209 * Returns an SurvivorAlignmentTestMain instance constructed using CLI
210 * options.
211 *
212 * Following options are expected:
213 * <ul>
214 * <li>memoryToFill</li>
215 * <li>objectSize</li>
216 * </ul>
217 *
218 * Both argument may contain multiplier suffix k, m or g.
219 */
220 public static SurvivorAlignmentTestMain fromArgs(String[] args) {
221 Asserts.assertEQ(args.length, 3, "Expected three arguments: "
222 + "memory size, object size and tested heap space name.");
223
224 long memoryToFill = parseSize(args[0]);
225 long objectSize = Math.max(parseSize(args[1]),
226 AlignmentHelper.MIN_ARRAY_SIZE);
227 HeapSpace testedSpace = HeapSpace.valueOf(args[2]);
228
229 return new SurvivorAlignmentTestMain(memoryToFill, objectSize,
230 testedSpace);
231 }
232
233 /**
234 * Returns a value parsed from a string with format
235 * <integer><multiplier>.
236 */
237 private static long parseSize(String sizeString) {
238 Matcher matcher = SIZE_REGEX.matcher(sizeString);
239 Asserts.assertTrue(matcher.matches(),
240 "sizeString should have following format \"[0-9]+([MBK])?\"");
241 long size = Long.valueOf(matcher.group("size"));
242
243 if (matcher.group("multiplier") != null) {
244 long K = 1024L;
245 // fall through multipliers
246 switch (matcher.group("multiplier").toLowerCase()) {
247 case "g":
248 size *= K;
249 case "m":
250 size *= K;
251 case "k":
252 size *= K;
253 }
254 }
255 return size;
256 }
257
258 private SurvivorAlignmentTestMain(long memoryToFill, long objectSize,
259 HeapSpace testedSpace) {
260 this.objectSize = objectSize;
261 this.memoryToFill = memoryToFill;
262 this.testedSpace = testedSpace;
263
264 AlignmentHelper helper = SurvivorAlignmentTestMain.EDEN_SPACE_HELPER;
265
266 this.actualObjectSize = helper.getObjectSizeInThisSpace(
267 this.objectSize);
268 int arrayLength = helper.getObjectsCount(memoryToFill, this.objectSize);
269 garbage = new Object[arrayLength];
270 }
271
272 /**
273 * Allocate byte arrays to fill {@code memoryToFill} memory.
274 */
275 public void allocate() {
276 int byteArrayLength = Math.max((int) (objectSize
277 - Unsafe.ARRAY_BYTE_BASE_OFFSET), 0);
278
279 for (int i = 0; i < garbage.length; i++) {
280 garbage[i] = new byte[byteArrayLength];
281 }
282 }
283
284 /**
285 * Release memory occupied after {@code allocate} call.
286 */
287 public void release() {
288 for (int i = 0; i < garbage.length; i++) {
289 garbage[i] = null;
290 }
291 }
292
293 /**
294 * Returns expected amount of memory occupied in a {@code heapSpace} by
295 * objects referenced from {@code garbage} array.
296 */
297 public long getExpectedMemoryUsage() {
298 AlignmentHelper alignmentHelper = getAlignmentHelper(testedSpace);
299 return alignmentHelper.getExpectedMemoryUsage(objectSize,
300 garbage.length);
301 }
302
303 /**
304 * Verifies that memory usage in a {@code heapSpace} deviates from
305 * {@code expectedUsage} for no more than {@code MAX_RELATIVE_DEVIATION}.
306 */
307 public void verifyMemoryUsage(long expectedUsage) {
308 AlignmentHelper alignmentHelper = getAlignmentHelper(testedSpace);
309
310 long actualMemoryUsage = alignmentHelper.getActualMemoryUsage();
311 boolean otherThreadsAllocatedMemory = areOtherThreadsAllocatedMemory();
312
313 long memoryUsageDiff = Math.abs(actualMemoryUsage - expectedUsage);
314 long maxAllowedUsageDiff
315 = alignmentHelper.getAllowedMemoryUsageDeviation(expectedUsage);
316
317 System.out.println("Verifying memory usage in space: " + testedSpace);
318 System.out.println("Allocated objects count: " + garbage.length);
319 System.out.println("Desired object size: " + objectSize);
320 System.out.println("Actual object size: " + actualObjectSize);
321 System.out.println("Expected object size in space: "
322 + alignmentHelper.getObjectSizeInThisSpace(objectSize));
323 System.out.println("Expected memory usage: " + expectedUsage);
324 System.out.println("Actual memory usage: " + actualMemoryUsage);
325 System.out.println("Memory usage diff: " + memoryUsageDiff);
326 System.out.println("Max allowed usage diff: " + maxAllowedUsageDiff);
327
328 if (memoryUsageDiff > maxAllowedUsageDiff
329 && otherThreadsAllocatedMemory) {
330 System.out.println("Memory usage diff is incorrect, but it seems "
331 + "like someone else allocated objects");
332 return;
333 }
334
335 Asserts.assertLTE(memoryUsageDiff, maxAllowedUsageDiff,
336 "Actual memory usage should not deviate from expected for " +
337 "more then " + maxAllowedUsageDiff);
338 }
339
340 /**
341 * Baselines amount of memory allocated by each thread.
342 */
343 public void baselineMemoryAllocation() {
344 ThreadMXBean bean = (ThreadMXBean) ManagementFactory.getThreadMXBean();
345 threadIds = bean.getAllThreadIds();
346 baselinedThreadMemoryUsage = bean.getThreadAllocatedBytes(threadIds);
347 }
348
349 /**
350 * Checks if threads other then the current thread were allocating objects
351 * after baselinedThreadMemoryUsage call.
352 *
353 * If baselinedThreadMemoryUsage was not called, then this method will return
354 * {@code false}.
355 */
356 public boolean areOtherThreadsAllocatedMemory() {
357 if (baselinedThreadMemoryUsage == null) {
358 return false;
359 }
360
361 ThreadMXBean bean = (ThreadMXBean) ManagementFactory.getThreadMXBean();
362 long currentMemoryAllocation[]
363 = bean.getThreadAllocatedBytes(threadIds);
364 boolean otherThreadsAllocatedMemory = false;
365
366 System.out.println("Verifying amount of memory allocated by threads:");
367 for (int i = 0; i < threadIds.length; i++) {
368 System.out.format("Thread %d%nbaseline allocation: %d"
369 + "%ncurrent allocation:%d%n", threadIds[i],
370 baselinedThreadMemoryUsage[i], currentMemoryAllocation[i]);
371 System.out.println(bean.getThreadInfo(threadIds[i]));
372
373 long bytesAllocated = Math.abs(currentMemoryAllocation[i]
374 - baselinedThreadMemoryUsage[i]);
375 if (bytesAllocated > 0
376 && threadIds[i] != Thread.currentThread().getId()) {
377 otherThreadsAllocatedMemory = true;
378 }
379 }
380
381 return otherThreadsAllocatedMemory;
382 }
383
384 @Override
385 public String toString() {
386 StringBuilder builder = new StringBuilder();
387
388 builder.append(String.format("SurvivorAlignmentTestMain info:%n"));
389 builder.append(String.format("Desired object size: %d%n", objectSize));
390 builder.append(String.format("Memory to fill: %d%n", memoryToFill));
391 builder.append(String.format("Objects to be allocated: %d%n",
392 garbage.length));
393
394 builder.append(String.format("Alignment helpers to be used: %n"));
395 for (HeapSpace heapSpace: HeapSpace.values()) {
396 builder.append(String.format("For space %s:%n%s%n", heapSpace,
397 getAlignmentHelper(heapSpace)));
398 }
399
400 return builder.toString();
401 }
402
403 /**
404 * Returns {@code AlignmentHelper} for a space {@code heapSpace}.
405 */
406 public static AlignmentHelper getAlignmentHelper(HeapSpace heapSpace) {
407 switch (heapSpace) {
408 case EDEN:
409 return SurvivorAlignmentTestMain.EDEN_SPACE_HELPER;
410 case SURVIVOR:
411 return SurvivorAlignmentTestMain.SURVIVOR_SPACE_HELPER;
412 case TENURED:
413 return SurvivorAlignmentTestMain.TENURED_SPACE_HELPER;
414 default:
415 throw new Error("Unexpected heap space: " + heapSpace);
416 }
417 }
418 }