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1   /*
2    * Copyright (c) 2009, 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.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package sun.misc;
27  
28  import java.nio.ByteBuffer;
29  import java.nio.ByteOrder;
30  import java.nio.LongBuffer;
31  import java.security.AccessController;
32  
33  /**
34   * Performance counter support for internal JRE classes.
35   * This class defines a fixed list of counters for the platform
36   * to use as an interim solution until RFE# 6209222 is implemented.
37   * The perf counters will be created in the jvmstat perf buffer
38   * that the HotSpot VM creates. The default size is 32K and thus
39   * the number of counters is bounded.  You can alter the size
40   * with -XX:PerfDataMemorySize=<bytes> option. If there is
41   * insufficient memory in the jvmstat perf buffer, the C heap memory
42   * will be used and thus the application will continue to run if
43   * the counters added exceeds the buffer size but the counters
44   * will be missing.
45   *
46   * See HotSpot jvmstat implementation for certain circumstances
47   * that the jvmstat perf buffer is not supported.
48   *
49   */
50  public class PerfCounter {
51      private static final Perf perf =
52          AccessController.doPrivileged(new Perf.GetPerfAction());
53  
54      // Must match values defined in hotspot/src/share/vm/runtime/perfdata.hpp
55      private final static int V_Constant  = 1;
56      private final static int V_Monotonic = 2;
57      private final static int V_Variable  = 3;
58      private final static int U_None      = 1;
59  
60      private final String name;
61      private final LongBuffer lb;
62  
63      private PerfCounter(String name, int type) {
64          this.name = name;
65          ByteBuffer bb = perf.createLong(name, type, U_None, 0L);
66          bb.order(ByteOrder.nativeOrder());
67          this.lb = bb.asLongBuffer();
68      }
69  
70      static PerfCounter newPerfCounter(String name) {
71          return new PerfCounter(name, V_Variable);
72      }
73  
74      static PerfCounter newConstantPerfCounter(String name) {
75          PerfCounter c = new PerfCounter(name, V_Constant);
76          return c;
77      }
78  
79      /**
80       * Returns the current value of the perf counter.
81       */
82      public synchronized long get() {
83          return lb.get(0);
84      }
85  
86      /**
87       * Sets the value of the perf counter to the given newValue.
88       */
89      public synchronized void set(long newValue) {
90          lb.put(0, newValue);
91      }
92  
93      /**
94       * Adds the given value to the perf counter.
95       */
96      public synchronized void add(long value) {
97          long res = get() + value;
98          lb.put(0, res);
99      }
100 
101     /**
102      * Increments the perf counter with 1.
103      */
104     public void increment() {
105         add(1);
106     }
107 
108     /**
109      * Adds the given interval to the perf counter.
110      */
111     public void addTime(long interval) {
112         add(interval);
113     }
114 
115     /**
116      * Adds the elapsed time from the given start time (ns) to the perf counter.
117      */
118     public void addElapsedTimeFrom(long startTime) {
119         add(System.nanoTime() - startTime);
120     }
121 
122     @Override
123     public String toString() {
124         return name + " = " + get();
125     }
126 
127     static class CoreCounters {
128         static final PerfCounter pdt   = newPerfCounter("sun.classloader.parentDelegationTime");
129         static final PerfCounter lc    = newPerfCounter("sun.classloader.findClasses");
130         static final PerfCounter lct   = newPerfCounter("sun.classloader.findClassTime");
131         static final PerfCounter rcbt  = newPerfCounter("sun.urlClassLoader.readClassBytesTime");
132         static final PerfCounter zfc   = newPerfCounter("sun.zip.zipFiles");
133         static final PerfCounter zfot  = newPerfCounter("sun.zip.zipFile.openTime");
134     }
135 
136     static class WindowsClientCounters {
137         static final PerfCounter d3dAvailable = newConstantPerfCounter("sun.java2d.d3d.available");
138     }
139 
140     /**
141      * Number of findClass calls
142      */
143     public static PerfCounter getFindClasses() {
144         return CoreCounters.lc;
145     }
146 
147     /**
148      * Time (ns) spent in finding classes that includes
149      * lookup and read class bytes and defineClass
150      */
151     public static PerfCounter getFindClassTime() {
152         return CoreCounters.lct;
153     }
154 
155     /**
156      * Time (ns) spent in finding classes
157      */
158     public static PerfCounter getReadClassBytesTime() {
159         return CoreCounters.rcbt;
160     }
161 
162     /**
163      * Time (ns) spent in the parent delegation to
164      * the parent of the defining class loader
165      */
166     public static PerfCounter getParentDelegationTime() {
167         return CoreCounters.pdt;
168     }
169 
170     /**
171      * Number of zip files opened.
172      */
173     public static PerfCounter getZipFileCount() {
174         return CoreCounters.zfc;
175     }
176 
177     /**
178      * Time (ns) spent in opening the zip files that
179      * includes building the entries hash table
180      */
181     public static PerfCounter getZipFileOpenTime() {
182         return CoreCounters.zfot;
183     }
184 
185     /**
186      * D3D graphic pipeline available
187      */
188     public static PerfCounter getD3DAvailable() {
189         return WindowsClientCounters.d3dAvailable;
190     }
191 }