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.classfile.*;
32 import sun.jvm.hotspot.memory.*;
33 import sun.jvm.hotspot.oops.*;
34 import sun.jvm.hotspot.runtime.*;
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 @Override
53 public String getName() {
54 return "classLoaderStats";
55 }
56
57 public static void main(String[] args) {
58 ClassLoaderStats cls = new ClassLoaderStats();
59 cls.execute(args);
60 }
61
62 private static class ClassData {
63 Klass klass;
64 long size;
65
66 ClassData(Klass klass, long size) {
67 this.klass = klass; this.size = size;
68 }
69 }
70
71 private static class LoaderData {
72 long numClasses;
73 long classSize;
74 List classDetail = new ArrayList(); // List<ClassData>
75 }
76
77 public void run() {
78 printClassLoaderStatistics();
79 }
80
81 private void printClassLoaderStatistics() {
82 final PrintStream out = System.out;
83 final PrintStream err = System.err;
84 final Map loaderMap = new HashMap();
85 // loader data for bootstrap class loader
86 final LoaderData bootstrapLoaderData = new LoaderData();
87 if (verbose) {
88 err.print("finding class loader instances ..");
89 }
90
91 VM vm = VM.getVM();
92 ObjectHeap heap = vm.getObjectHeap();
93 Klass classLoaderKlass = vm.getSystemDictionary().getClassLoaderKlass();
94 try {
95 heap.iterateObjectsOfKlass(new DefaultHeapVisitor() {
96 public boolean doObj(Oop oop) {
97 loaderMap.put(oop, new LoaderData());
98 return false;
99 }
100 }, classLoaderKlass);
101 } catch (Exception se) {
102 se.printStackTrace();
103 }
104
105 if (verbose) {
106 err.println("done.");
107 err.print("computing per loader stat ..");
108 }
109
110 ClassLoaderDataGraph cldg = VM.getVM().getClassLoaderDataGraph();
111 cldg.classesDo(new ClassLoaderDataGraph.ClassVisitor() {
112 public void visit(Klass k) {
113 if (! (k instanceof InstanceKlass)) {
114 return;
115 }
116 Oop loader = ((InstanceKlass) k).getClassLoader();
117 LoaderData ld = (loader != null) ? (LoaderData)loaderMap.get(loader)
118 : bootstrapLoaderData;
119 if (ld != null) {
120 ld.numClasses++;
121 long size = computeSize((InstanceKlass)k);
122 ld.classDetail.add(new ClassData(k, size));
123 ld.classSize += size;
124 }
125 }
126 });
127
128 if (verbose) {
129 err.println("done.");
130 err.print("please wait.. computing liveness");
131 }
132
133 // compute reverse pointer analysis (takes long time for larger app)
134 ReversePtrsAnalysis analysis = new ReversePtrsAnalysis();
135
136 if (verbose) {
137 analysis.setHeapProgressThunk(new HeapProgressThunk() {
138 public void heapIterationFractionUpdate(double fractionOfHeapVisited) {
139 err.print('.');
140 }
141 // This will be called after the iteration is complete
142 public void heapIterationComplete() {
143 err.println("done.");
144 }
145 });
146 }
147
148 try {
149 analysis.run();
150 } catch (Exception e) {
151 // e.printStackTrace();
152 if (verbose)
153 err.println("liveness analysis may be inaccurate ...");
154 }
155 ReversePtrs liveness = VM.getVM().getRevPtrs();
156
157 out.println("class_loader\tclasses\tbytes\tparent_loader\talive?\ttype");
158 out.println();
159
160 long numClassLoaders = 1L;
161 long totalNumClasses = bootstrapLoaderData.numClasses;
162 long totalClassSize = bootstrapLoaderData.classSize;
163 long numAliveLoaders = 1L;
164 long numDeadLoaders = 0L;
165
166 // print bootstrap loader details
167 out.print("<bootstrap>");
168 out.print('\t');
169 out.print(bootstrapLoaderData.numClasses);
170 out.print('\t');
171 out.print(bootstrapLoaderData.classSize);
172 out.print('\t');
173 out.print(" null ");
174 out.print('\t');
175 // bootstrap loader is always alive
176 out.print("live");
177 out.print('\t');
178 out.println("<internal>");
179
180 for (Iterator keyItr = loaderMap.keySet().iterator(); keyItr.hasNext();) {
181 Oop loader = (Oop) keyItr.next();
182 LoaderData data = (LoaderData) loaderMap.get(loader);
183 numClassLoaders ++;
184 totalNumClasses += data.numClasses;
185 totalClassSize += data.classSize;
186
187 out.print(loader.getHandle());
188 out.print('\t');
189 out.print(data.numClasses);
190 out.print('\t');
191 out.print(data.classSize);
192 out.print('\t');
193
194 class ParentFinder extends DefaultOopVisitor {
195 public void doOop(OopField field, boolean isVMField) {
196 if (field.getID().getName().equals("parent")) {
197 parent = field.getValue(getObj());
198 }
199 }
200 private Oop parent = null;
201 public Oop getParent() { return parent; }
202 }
203
204 ParentFinder parentFinder = new ParentFinder();
205 loader.iterate(parentFinder, false);
206 Oop parent = parentFinder.getParent();
207 out.print((parent != null)? parent.getHandle().toString() : " null ");
208 out.print('\t');
209 boolean alive = (liveness != null) ? (liveness.get(loader) != null) : true;
210 out.print(alive? "live" : "dead");
211 if (alive) numAliveLoaders++; else numDeadLoaders++;
212 out.print('\t');
213 Klass loaderKlass = loader.getKlass();
214 if (loaderKlass != null) {
215 out.print(loaderKlass.getName().asString());
216 out.print('@');
217 out.print(loader.getKlass().getAddress());
218 } else {
219 out.print(" null! ");
220 }
221 out.println();
222 }
223
224 out.println();
225 // summary line
226 out.print("total = ");
227 out.print(numClassLoaders);
228 out.print('\t');
229 out.print(totalNumClasses);
230 out.print('\t');
231 out.print(totalClassSize);
232 out.print('\t');
233 out.print(" N/A ");
234 out.print('\t');
235 out.print("alive=");
236 out.print(numAliveLoaders);
237 out.print(", dead=");
238 out.print(numDeadLoaders);
239 out.print('\t');
240 out.print(" N/A ");
241 out.println();
242 }
243
244 private static long objectSize(Oop oop) {
245 return oop == null ? 0L : oop.getObjectSize();
246 }
247
248 // Don't count the shared empty arrays
249 private static long arraySize(GenericArray arr) {
250 return arr.getLength() != 0L ? arr.getSize() : 0L;
251 }
252
253 private long computeSize(InstanceKlass k) {
254 long size = 0L;
255 // the InstanceKlass object itself
256 size += k.getSize();
257
258 // Constant pool
259 ConstantPool cp = k.getConstants();
260 size += cp.getSize();
261 if (cp.getCache() != null) {
262 size += cp.getCache().getSize();
263 }
264 size += arraySize(cp.getTags());
265
266 // Interfaces
267 size += arraySize(k.getLocalInterfaces());
268 size += arraySize(k.getTransitiveInterfaces());
269
270 // Inner classes
271 size += arraySize(k.getInnerClasses());
272
273 // Fields
274 size += arraySize(k.getFields());
275
276 // Methods
277 MethodArray methods = k.getMethods();
278 int nmethods = (int) methods.getLength();
279 if (nmethods != 0L) {
280 size += methods.getSize();
281 for (int i = 0; i < nmethods; ++i) {
282 Method m = methods.at(i);
283 size += m.getSize();
284 size += m.getConstMethod().getSize();
285 }
286 }
287
288 return size;
289 }
290 }