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    1   /*
    2    * Copyright (c) 2009, 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, U_None, type, 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   }

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