org.spf4j.stackmonitor

Class Sampler

java.lang.Object

org.spf4j.stackmonitor.Sampler

@ThreadSafe
public final class Sampler
extends Object

Utility to sample stack traces. Stack traces can be persisted for later analysis. please read http://sape.inf.usi.ch/sites/default/files/publication/pldi10.pdf pure java stack sampling will probably have safepoint bias.

Author:

zoly

Constructor Summary

Constructors

Constructor and Description
Sampler()
Sampler(int sampleTimeMillis)
Sampler(int sampleTimeMillis, int dumpTimeMillis, StackCollector collector)
Sampler(int sampleTimeMillis, int dumpTimeMillis, StackCollector collector, String dumpFolder, String dumpFilePrefix)
Sampler(StackCollector collector)

Method Summary

Methods

Modifier and Type	Method and Description
void	clear()
void	dispose()
String	dumpToFile()
String	dumpToFile(String id) Dumps the sampled stacks to file.
int	getDumpTimeMillis()
int	getSampleTimeMillis()
StackCollector	getStackCollector()
boolean	isStopped()
void	registerJmx()
void	setDumpTimeMillis(int dumpTimeMillis)
void	setSampleTimeMillis(int sampleTimeMillis)
void	start()
void	stop()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Sampler

public Sampler()

Sampler

public Sampler(int sampleTimeMillis)

Sampler

public Sampler(StackCollector collector)

Sampler

public Sampler(int sampleTimeMillis,
       int dumpTimeMillis,
       StackCollector collector)

Sampler

public Sampler(int sampleTimeMillis,
       int dumpTimeMillis,
       StackCollector collector,
       String dumpFolder,
       String dumpFilePrefix)

Method Detail

registerJmx

public void registerJmx()

start

public void start()

dumpToFile

public String dumpToFile()
                  throws IOException

Throws:

IOException

dumpToFile

public String dumpToFile(@Nullable
                String id)
                  throws IOException

Dumps the sampled stacks to file. the collected samples are reset

Parameters:

id - - id will be added to file name returns the name of the file.

Throws:

IOException

stop

public void stop()
          throws InterruptedException

Throws:

InterruptedException

getSampleTimeMillis

public int getSampleTimeMillis()

setSampleTimeMillis

public void setSampleTimeMillis(int sampleTimeMillis)

isStopped

public boolean isStopped()

clear

public void clear()

getStackCollector

public StackCollector getStackCollector()

dispose

@PreDestroy
public void dispose()
             throws InterruptedException

Throws:

InterruptedException

getDumpTimeMillis

public int getDumpTimeMillis()

setDumpTimeMillis

public void setDumpTimeMillis(int dumpTimeMillis)