Package org.apache.hadoop.metrics2.source

Class JvmMetrics

java.lang.Object

org.apache.hadoop.metrics2.source.JvmMetrics

All Implemented Interfaces:

MetricsSource

@Private
public class JvmMetrics
extends Object
implements MetricsSource

JVM and logging related metrics. Mostly used by various servers as a part of the metrics they export.

Field Summary

Fields

Modifier and Type	Field	Description
static final float	MEMORY_MAX_UNLIMITED_MB

Method Summary

Modifier and Type	Method	Description
static JvmMetrics	create(String processName, String sessionId, MetricsSystem ms)
void	getMetrics(MetricsCollector collector, boolean all)	Get metrics from the metrics source
static JvmMetrics	initSingleton(String processName, String sessionId)
static void	reattach(MetricsSystem ms, JvmMetrics jvmMetrics)
void	registerIfNeeded()
void	setGcTimeMonitor(GcTimeMonitor gcTimeMonitor)
void	setPauseMonitor(JvmPauseMonitor pauseMonitor)
static void	shutdownSingleton()	Shutdown the JvmMetrics singleton.

Methods inherited from class java.lang.Object

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

Field Details

MEMORY_MAX_UNLIMITED_MB

public static final float MEMORY_MAX_UNLIMITED_MB

See Also:

• Constant Field Values

Method Details

registerIfNeeded

@VisibleForTesting
public void registerIfNeeded()

setPauseMonitor

public void setPauseMonitor(JvmPauseMonitor pauseMonitor)

setGcTimeMonitor

public void setGcTimeMonitor(GcTimeMonitor gcTimeMonitor)

create

public static JvmMetrics create(String processName,
 String sessionId,
 MetricsSystem ms)

reattach

public static void reattach(MetricsSystem ms,
 JvmMetrics jvmMetrics)

initSingleton

public static JvmMetrics initSingleton(String processName,
 String sessionId)

shutdownSingleton

public static void shutdownSingleton()

Shutdown the JvmMetrics singleton. This is not necessary if the JVM itself is shutdown, but may be necessary for scenarios where JvmMetrics instance needs to be re-created while the JVM is still around. One such scenario is unit-testing.

getMetrics

public void getMetrics(MetricsCollector collector,
 boolean all)

Description copied from interface: MetricsSource

Get metrics from the metrics source

Specified by:

getMetrics in interface MetricsSource

Parameters:

collector - to contain the resulting metrics snapshot

all - if true, return all metrics even if unchanged.