1 /*
2 * Copyright (c) 2003, 2013, 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 package sun.jvm.hotspot.tools;
26
27 import java.io.*;
28 import java.util.*;
29
30 import sun.jvm.hotspot.debugger.*;
31 import sun.jvm.hotspot.memory.*;
32 import sun.jvm.hotspot.oops.*;
33 import sun.jvm.hotspot.runtime.*;
34 import sun.jvm.hotspot.tools.*;
35 import sun.jvm.hotspot.utilities.*;
36
37 /**
38 A command line tool to print class loader statistics.
39 */
40
41 public class ClassLoaderStats extends Tool {
42 boolean verbose = true;
43
44 public ClassLoaderStats() {
45 super();
46 }
47
48 public ClassLoaderStats(JVMDebugger d) {
49 super(d);
50 }
51
52 public static void main(String[] args) {
53 ClassLoaderStats cls = new ClassLoaderStats();
54 cls.start(args);
55 cls.stop();
56 }
57
58 private static class ClassData {
59 Klass klass;
60 long size;
61
62 ClassData(Klass klass, long size) {
63 this.klass = klass; this.size = size;
64 }
65 }
66
67 private static class LoaderData {
68 long numClasses;
69 long classSize;
70 List classDetail = new ArrayList(); // List<ClassData>
71 }
72
73 public void run() {
74 printClassLoaderStatistics();
75 }
76
77 private void printClassLoaderStatistics() {
78 final PrintStream out = System.out;
79 final PrintStream err = System.err;
80 final Map loaderMap = new HashMap();
81 // loader data for bootstrap class loader
82 final LoaderData bootstrapLoaderData = new LoaderData();
83 if (verbose) {
84 err.print("finding class loader instances ..");
85 }
86
87 VM vm = VM.getVM();
88 ObjectHeap heap = vm.getObjectHeap();
89 Klass classLoaderKlass = vm.getSystemDictionary().getClassLoaderKlass();
90 try {
91 heap.iterateObjectsOfKlass(new DefaultHeapVisitor() {
92 public boolean doObj(Oop oop) {
93 loaderMap.put(oop, new LoaderData());
94 return false;
95 }
96 }, classLoaderKlass);
97 } catch (Exception se) {
98 se.printStackTrace();
99 }
100
101 if (verbose) {
102 err.println("done.");
103 err.print("computing per loader stat ..");
104 }
105
106 SystemDictionary dict = VM.getVM().getSystemDictionary();
107 dict.classesDo(new SystemDictionary.ClassAndLoaderVisitor() {
108 public void visit(Klass k, Oop loader) {
109 if (! (k instanceof InstanceKlass)) {
110 return;
111 }
112 LoaderData ld = (loader != null) ? (LoaderData)loaderMap.get(loader)
113 : bootstrapLoaderData;
114 if (ld != null) {
115 ld.numClasses++;
116 long size = computeSize((InstanceKlass)k);
117 ld.classDetail.add(new ClassData(k, size));
118 ld.classSize += size;
119 }
120 }
121 });
122
123 if (verbose) {
124 err.println("done.");
125 err.print("please wait.. computing liveness");
126 }
127
128 // compute reverse pointer analysis (takes long time for larger app)
129 ReversePtrsAnalysis analysis = new ReversePtrsAnalysis();
130
131 if (verbose) {
132 analysis.setHeapProgressThunk(new HeapProgressThunk() {
133 public void heapIterationFractionUpdate(double fractionOfHeapVisited) {
134 err.print('.');
135 }
136 // This will be called after the iteration is complete
137 public void heapIterationComplete() {
138 err.println("done.");
139 }
140 });
141 }
142
143 try {
144 analysis.run();
145 } catch (Exception e) {
146 // e.printStackTrace();
147 if (verbose)
148 err.println("liveness analysis may be inaccurate ...");
149 }
150 ReversePtrs liveness = VM.getVM().getRevPtrs();
151
152 out.println("class_loader\tclasses\tbytes\tparent_loader\talive?\ttype");
153 out.println();
154
155 long numClassLoaders = 1L;
156 long totalNumClasses = bootstrapLoaderData.numClasses;
157 long totalClassSize = bootstrapLoaderData.classSize;
158 long numAliveLoaders = 1L;
159 long numDeadLoaders = 0L;
160
161 // print bootstrap loader details
162 out.print("<bootstrap>");
163 out.print('\t');
164 out.print(bootstrapLoaderData.numClasses);
165 out.print('\t');
166 out.print(bootstrapLoaderData.classSize);
167 out.print('\t');
168 out.print(" null ");
169 out.print('\t');
170 // bootstrap loader is always alive
171 out.print("live");
172 out.print('\t');
173 out.println("<internal>");
174
175 for (Iterator keyItr = loaderMap.keySet().iterator(); keyItr.hasNext();) {
176 Oop loader = (Oop) keyItr.next();
177 LoaderData data = (LoaderData) loaderMap.get(loader);
178 numClassLoaders ++;
179 totalNumClasses += data.numClasses;
180 totalClassSize += data.classSize;
181
182 out.print(loader.getHandle());
183 out.print('\t');
184 out.print(data.numClasses);
185 out.print('\t');
186 out.print(data.classSize);
187 out.print('\t');
188
189 class ParentFinder extends DefaultOopVisitor {
190 public void doOop(OopField field, boolean isVMField) {
191 if (field.getID().getName().equals("parent")) {
192 parent = field.getValue(getObj());
193 }
194 }
195 private Oop parent = null;
196 public Oop getParent() { return parent; }
197 }
198
199 ParentFinder parentFinder = new ParentFinder();
200 loader.iterate(parentFinder, false);
201 Oop parent = parentFinder.getParent();
202 out.print((parent != null)? parent.getHandle().toString() : " null ");
203 out.print('\t');
204 boolean alive = (liveness != null) ? (liveness.get(loader) != null) : true;
205 out.print(alive? "live" : "dead");
206 if (alive) numAliveLoaders++; else numDeadLoaders++;
207 out.print('\t');
208 Klass loaderKlass = loader.getKlass();
209 if (loaderKlass != null) {
210 out.print(loaderKlass.getName().asString());
211 out.print('@');
212 out.print(loader.getKlass().getAddress());
213 } else {
214 out.print(" null! ");
215 }
216 out.println();
217 }
218
219 out.println();
220 // summary line
221 out.print("total = ");
222 out.print(numClassLoaders);
223 out.print('\t');
224 out.print(totalNumClasses);
225 out.print('\t');
226 out.print(totalClassSize);
227 out.print('\t');
228 out.print(" N/A ");
229 out.print('\t');
230 out.print("alive=");
231 out.print(numAliveLoaders);
232 out.print(", dead=");
233 out.print(numDeadLoaders);
234 out.print('\t');
235 out.print(" N/A ");
236 out.println();
237 }
238
239 private static long objectSize(Oop oop) {
240 return oop == null ? 0L : oop.getObjectSize();
241 }
242
243 // Don't count the shared empty arrays
244 private static long arraySize(GenericArray arr) {
245 return arr.getLength() != 0L ? arr.getSize() : 0L;
246 }
247
248 private long computeSize(InstanceKlass k) {
249 long size = 0L;
250 // the InstanceKlass object itself
251 size += k.getSize();
252
253 // Constant pool
254 ConstantPool cp = k.getConstants();
255 size += cp.getSize();
256 if (cp.getCache() != null) {
257 size += cp.getCache().getSize();
258 }
259 size += arraySize(cp.getTags());
260
261 // Interfaces
262 size += arraySize(k.getLocalInterfaces());
263 size += arraySize(k.getTransitiveInterfaces());
264
265 // Inner classes
266 size += arraySize(k.getInnerClasses());
267
268 // Fields
269 size += arraySize(k.getFields());
270
271 // Methods
272 MethodArray methods = k.getMethods();
273 int nmethods = (int) methods.getLength();
274 if (nmethods != 0L) {
275 size += methods.getSize();
276 for (int i = 0; i < nmethods; ++i) {
277 Method m = methods.at(i);
278 size += m.getSize();
279 size += m.getConstMethod().getSize();
280 }
281 }
282
283 return size;
284 }
285 }