1 /*
2 * Copyright (c) 2014, 2015, 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 = "G1 Old Gen";
75
76 private static final long G1_HEAP_REGION_SIZE = Optional.ofNullable(
77 SurvivorAlignmentTestMain.WHITE_BOX.getUintxVMFlag(
78 "G1HeapRegionSize")).orElse(-1L);
79
80 /**
81 * Min size of free chunk in CMS generation.
82 * An object allocated in CMS generation will at least occupy this amount
83 * of bytes.
84 */
85 private static final long CMS_MIN_FREE_CHUNK_SIZE
86 = 3L * Unsafe.ADDRESS_SIZE;
87
88 private static final AlignmentHelper EDEN_SPACE_HELPER;
89 private static final AlignmentHelper SURVIVOR_SPACE_HELPER;
90 private static final AlignmentHelper TENURED_SPACE_HELPER;
91 /**
92 * Amount of memory that should be filled during a test run.
93 */
94 private final long memoryToFill;
95 /**
96 * The size of an objects that will be allocated during a test run.
97 */
98 private final long objectSize;
99 /**
100 * Amount of memory that will be actually occupied by an object in eden
101 * space.
102 */
103 private final long actualObjectSize;
104 /**
105 * Storage for allocated objects.
106 */
107 private final Object[] garbage;
108 /**
109 * Heap space whose memory usage is a subject of assertions during the test
110 * run.
111 */
112 private final HeapSpace testedSpace;
113
114 private long[] baselinedThreadMemoryUsage = null;
115 private long[] threadIds = null;
116
117 /**
118 * Initialize {@code EDEN_SPACE_HELPER}, {@code SURVIVOR_SPACE_HELPER} and
119 * {@code TENURED_SPACE_HELPER} to represent heap spaces in use.
120 *
121 * Note that regardless to GC object's alignment in survivor space is
122 * expected to be equal to {@code SurvivorAlignmentInBytes} value and
123 * alignment in other spaces is expected to be equal to
124 * {@code ObjectAlignmentInBytes} value.
125 *
126 * In CMS generation we can't allocate less then {@code MinFreeChunk} value,
127 * for other CGs we expect that object of size {@code MIN_OBJECT_SIZE}
128 * could be allocated as it is (of course, its size could be aligned
129 * according to alignment value used in a particular space).
130 *
131 * For G1 GC MXBeans could report memory usage only with region size
132 * precision (if an object allocated in some G1 heap region, then all region
133 * will claimed as used), so for G1's spaces precision is equal to
134 * {@code G1HeapRegionSize} value.
135 */
136 static {
137 AlignmentHelper edenHelper = null;
138 AlignmentHelper survivorHelper = null;
139 AlignmentHelper tenuredHelper = null;
140 for (MemoryPoolMXBean pool : ManagementFactory.getMemoryPoolMXBeans()) {
141 switch (pool.getName()) {
142 case SurvivorAlignmentTestMain.DEF_NEW_EDEN:
143 case SurvivorAlignmentTestMain.PAR_NEW_EDEN:
144 case SurvivorAlignmentTestMain.PS_EDEN:
145 Asserts.assertNull(edenHelper,
146 "Only one bean for eden space is expected.");
147 edenHelper = new AlignmentHelper(
148 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
149 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
150 AlignmentHelper.MIN_OBJECT_SIZE, pool);
151 break;
152 case SurvivorAlignmentTestMain.G1_EDEN:
153 Asserts.assertNull(edenHelper,
154 "Only one bean for eden space is expected.");
155 edenHelper = new AlignmentHelper(
156 SurvivorAlignmentTestMain.G1_HEAP_REGION_SIZE,
157 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
158 AlignmentHelper.MIN_OBJECT_SIZE, pool);
159 break;
160 case SurvivorAlignmentTestMain.DEF_NEW_SURVIVOR:
161 case SurvivorAlignmentTestMain.PAR_NEW_SURVIVOR:
162 case SurvivorAlignmentTestMain.PS_SURVIVOR:
163 Asserts.assertNull(survivorHelper,
164 "Only one bean for survivor space is expected.");
165 survivorHelper = new AlignmentHelper(
166 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
167 AlignmentHelper.SURVIVOR_ALIGNMENT_IN_BYTES,
168 AlignmentHelper.MIN_OBJECT_SIZE, pool);
169 break;
170 case SurvivorAlignmentTestMain.G1_SURVIVOR:
171 Asserts.assertNull(survivorHelper,
172 "Only one bean for survivor space is expected.");
173 survivorHelper = new AlignmentHelper(
174 SurvivorAlignmentTestMain.G1_HEAP_REGION_SIZE,
175 AlignmentHelper.SURVIVOR_ALIGNMENT_IN_BYTES,
176 AlignmentHelper.MIN_OBJECT_SIZE, pool);
177 break;
178 case SurvivorAlignmentTestMain.SERIAL_TENURED:
179 case SurvivorAlignmentTestMain.PS_TENURED:
180 case SurvivorAlignmentTestMain.G1_TENURED:
181 Asserts.assertNull(tenuredHelper,
182 "Only one bean for tenured space is expected.");
183 tenuredHelper = new AlignmentHelper(
184 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
185 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
186 AlignmentHelper.MIN_OBJECT_SIZE, pool);
187 break;
188 case SurvivorAlignmentTestMain.CMS_TENURED:
189 Asserts.assertNull(tenuredHelper,
190 "Only one bean for tenured space is expected.");
191 tenuredHelper = new AlignmentHelper(
192 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
193 AlignmentHelper.OBJECT_ALIGNMENT_IN_BYTES,
194 SurvivorAlignmentTestMain.CMS_MIN_FREE_CHUNK_SIZE,
195 pool);
196 break;
197 }
198 }
199 EDEN_SPACE_HELPER = Objects.requireNonNull(edenHelper,
200 "AlignmentHelper for eden space should be initialized.");
201 SURVIVOR_SPACE_HELPER = Objects.requireNonNull(survivorHelper,
202 "AlignmentHelper for survivor space should be initialized.");
203 TENURED_SPACE_HELPER = Objects.requireNonNull(tenuredHelper,
204 "AlignmentHelper for tenured space should be initialized.");
205 }
206 /**
207 * Returns an SurvivorAlignmentTestMain instance constructed using CLI
208 * options.
209 *
210 * Following options are expected:
211 * <ul>
212 * <li>memoryToFill</li>
213 * <li>objectSize</li>
214 * </ul>
215 *
216 * Both argument may contain multiplier suffix k, m or g.
217 */
218 public static SurvivorAlignmentTestMain fromArgs(String[] args) {
219 Asserts.assertEQ(args.length, 3, "Expected three arguments: "
220 + "memory size, object size and tested heap space name.");
221
222 long memoryToFill = parseSize(args[0]);
223 long objectSize = Math.max(parseSize(args[1]),
224 AlignmentHelper.MIN_ARRAY_SIZE);
225 HeapSpace testedSpace = HeapSpace.valueOf(args[2]);
226
227 return new SurvivorAlignmentTestMain(memoryToFill, objectSize,
228 testedSpace);
229 }
230
231 /**
232 * Returns a value parsed from a string with format
233 * <integer><multiplier>.
234 */
235 private static long parseSize(String sizeString) {
236 Matcher matcher = SIZE_REGEX.matcher(sizeString);
237 Asserts.assertTrue(matcher.matches(),
238 "sizeString should have following format \"[0-9]+([MBK])?\"");
239 long size = Long.valueOf(matcher.group("size"));
240
241 if (matcher.group("multiplier") != null) {
242 long K = 1024L;
243 // fall through multipliers
244 switch (matcher.group("multiplier").toLowerCase()) {
245 case "g":
246 size *= K;
247 case "m":
248 size *= K;
249 case "k":
250 size *= K;
251 }
252 }
253 return size;
254 }
255
256 private SurvivorAlignmentTestMain(long memoryToFill, long objectSize,
257 HeapSpace testedSpace) {
258 this.objectSize = objectSize;
259 this.memoryToFill = memoryToFill;
260 this.testedSpace = testedSpace;
261
262 AlignmentHelper helper = SurvivorAlignmentTestMain.EDEN_SPACE_HELPER;
263
264 this.actualObjectSize = helper.getObjectSizeInThisSpace(
265 this.objectSize);
266 int arrayLength = helper.getObjectsCount(memoryToFill, this.objectSize);
267 garbage = new Object[arrayLength];
268 }
269
270 /**
271 * Allocate byte arrays to fill {@code memoryToFill} memory.
272 */
273 public void allocate() {
274 int byteArrayLength = Math.max((int) (objectSize
275 - Unsafe.ARRAY_BYTE_BASE_OFFSET), 0);
276
277 for (int i = 0; i < garbage.length; i++) {
278 garbage[i] = new byte[byteArrayLength];
279 }
280 }
281
282 /**
283 * Release memory occupied after {@code allocate} call.
284 */
285 public void release() {
286 for (int i = 0; i < garbage.length; i++) {
287 garbage[i] = null;
288 }
289 }
290
291 /**
292 * Returns expected amount of memory occupied in a {@code heapSpace} by
293 * objects referenced from {@code garbage} array.
294 */
295 public long getExpectedMemoryUsage() {
296 AlignmentHelper alignmentHelper = getAlignmentHelper(testedSpace);
297 return alignmentHelper.getExpectedMemoryUsage(objectSize,
298 garbage.length);
299 }
300
301 /**
302 * Verifies that memory usage in a {@code heapSpace} deviates from
303 * {@code expectedUsage} for no more than {@code MAX_RELATIVE_DEVIATION}.
304 */
305 public void verifyMemoryUsage(long expectedUsage) {
306 AlignmentHelper alignmentHelper = getAlignmentHelper(testedSpace);
307
308 long actualMemoryUsage = alignmentHelper.getActualMemoryUsage();
309 boolean otherThreadsAllocatedMemory = areOtherThreadsAllocatedMemory();
310
311 long memoryUsageDiff = Math.abs(actualMemoryUsage - expectedUsage);
312 long maxAllowedUsageDiff
313 = alignmentHelper.getAllowedMemoryUsageDeviation(expectedUsage);
314
315 System.out.println("Verifying memory usage in space: " + testedSpace);
316 System.out.println("Allocated objects count: " + garbage.length);
317 System.out.println("Desired object size: " + objectSize);
318 System.out.println("Actual object size: " + actualObjectSize);
319 System.out.println("Expected object size in space: "
320 + alignmentHelper.getObjectSizeInThisSpace(objectSize));
321 System.out.println("Expected memory usage: " + expectedUsage);
322 System.out.println("Actual memory usage: " + actualMemoryUsage);
323 System.out.println("Memory usage diff: " + memoryUsageDiff);
324 System.out.println("Max allowed usage diff: " + maxAllowedUsageDiff);
325
326 if (memoryUsageDiff > maxAllowedUsageDiff
327 && otherThreadsAllocatedMemory) {
328 System.out.println("Memory usage diff is incorrect, but it seems "
329 + "like someone else allocated objects");
330 return;
331 }
332
333 Asserts.assertLTE(memoryUsageDiff, maxAllowedUsageDiff,
334 "Actual memory usage should not deviate from expected for " +
335 "more then " + maxAllowedUsageDiff);
336 }
337
338 /**
339 * Baselines amount of memory allocated by each thread.
340 */
341 public void baselineMemoryAllocation() {
342 ThreadMXBean bean = (ThreadMXBean) ManagementFactory.getThreadMXBean();
343 threadIds = bean.getAllThreadIds();
344 baselinedThreadMemoryUsage = bean.getThreadAllocatedBytes(threadIds);
345 }
346
347 /**
348 * Checks if threads other then the current thread were allocating objects
349 * after baselinedThreadMemoryUsage call.
350 *
351 * If baselinedThreadMemoryUsage was not called, then this method will return
352 * {@code false}.
353 */
354 public boolean areOtherThreadsAllocatedMemory() {
355 if (baselinedThreadMemoryUsage == null) {
356 return false;
357 }
358
359 ThreadMXBean bean = (ThreadMXBean) ManagementFactory.getThreadMXBean();
360 long currentMemoryAllocation[]
361 = bean.getThreadAllocatedBytes(threadIds);
362 boolean otherThreadsAllocatedMemory = false;
363
364 System.out.println("Verifying amount of memory allocated by threads:");
365 for (int i = 0; i < threadIds.length; i++) {
366 System.out.format("Thread %d%nbaseline allocation: %d"
367 + "%ncurrent allocation:%d%n", threadIds[i],
368 baselinedThreadMemoryUsage[i], currentMemoryAllocation[i]);
369 System.out.println(bean.getThreadInfo(threadIds[i]));
370
371 long bytesAllocated = Math.abs(currentMemoryAllocation[i]
372 - baselinedThreadMemoryUsage[i]);
373 if (bytesAllocated > 0
374 && threadIds[i] != Thread.currentThread().getId()) {
375 otherThreadsAllocatedMemory = true;
376 }
377 }
378
379 return otherThreadsAllocatedMemory;
380 }
381
382 @Override
383 public String toString() {
384 StringBuilder builder = new StringBuilder();
385
386 builder.append(String.format("SurvivorAlignmentTestMain info:%n"));
387 builder.append(String.format("Desired object size: %d%n", objectSize));
388 builder.append(String.format("Memory to fill: %d%n", memoryToFill));
389 builder.append(String.format("Objects to be allocated: %d%n",
390 garbage.length));
391
392 builder.append(String.format("Alignment helpers to be used: %n"));
393 for (HeapSpace heapSpace: HeapSpace.values()) {
394 builder.append(String.format("For space %s:%n%s%n", heapSpace,
395 getAlignmentHelper(heapSpace)));
396 }
397
398 return builder.toString();
399 }
400
401 /**
402 * Returns {@code AlignmentHelper} for a space {@code heapSpace}.
403 */
404 public static AlignmentHelper getAlignmentHelper(HeapSpace heapSpace) {
405 switch (heapSpace) {
406 case EDEN:
407 return SurvivorAlignmentTestMain.EDEN_SPACE_HELPER;
408 case SURVIVOR:
409 return SurvivorAlignmentTestMain.SURVIVOR_SPACE_HELPER;
410 case TENURED:
411 return SurvivorAlignmentTestMain.TENURED_SPACE_HELPER;
412 default:
413 throw new Error("Unexpected heap space: " + heapSpace);
414 }
415 }
416 }