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public class: PerfCounter [javadoc | source]
Performance counter support for internal JRE classes. This class defines a fixed list of counters for the platform to use as an interim solution until RFE# 6209222 is implemented. The perf counters will be created in the jvmstat perf buffer that the HotSpot VM creates. The default size is 32K and thus the number of counters is bounded. You can alter the size with -XX:PerfDataMemorySize= option. If there is insufficient memory in the jvmstat perf buffer, the C heap memory will be used and thus the application will continue to run if the counters added exceeds the buffer size but the counters will be missing. See HotSpot jvmstat implementation for certain circumstances that the jvmstat perf buffer is not supported.
Nested Class Summary:
static class  PerfCounter.CoreCounters   
static class  PerfCounter.WindowsClientCounters   
Method from sun.misc.PerfCounter Summary:
add,   addElapsedTimeFrom,   addTime,   get,   getD3DAvailable,   getFindClassTime,   getFindClasses,   getParentDelegationTime,   getReadClassBytesTime,   getZipFileCount,   getZipFileOpenTime,   increment,   newConstantPerfCounter,   newPerfCounter,   set,   toString
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from sun.misc.PerfCounter Detail:
 public synchronized  void add(long value) 
    Adds the given value to the perf counter.
 public  void addElapsedTimeFrom(long startTime) 
    Adds the elapsed time from the given start time (ns) to the perf counter.
 public  void addTime(long interval) 
    Adds the given interval to the perf counter.
 public synchronized long get() 
    Returns the current value of the perf counter.
 public static PerfCounter getD3DAvailable() 
    D3D graphic pipeline available
 public static PerfCounter getFindClassTime() 
    Time (ns) spent in finding classes that includes lookup and read class bytes and defineClass
 public static PerfCounter getFindClasses() 
    Number of findClass calls
 public static PerfCounter getParentDelegationTime() 
    Time (ns) spent in the parent delegation to the parent of the defining class loader
 public static PerfCounter getReadClassBytesTime() 
    Time (ns) spent in finding classes
 public static PerfCounter getZipFileCount() 
    Number of zip files opened.
 public static PerfCounter getZipFileOpenTime() 
    Time (ns) spent in opening the zip files that includes building the entries hash table
 public  void increment() 
    Increments the perf counter with 1.
 static PerfCounter newConstantPerfCounter(String name) 
 static PerfCounter newPerfCounter(String name) 
 public synchronized  void set(long newValue) 
    Sets the value of the perf counter to the given newValue.
 public String toString()