org.jikesrvm.adaptive.measurements.listeners

Class CallDensityListener

java.lang.Object

org.jikesrvm.adaptive.measurements.listeners.Listener

org.jikesrvm.adaptive.measurements.listeners.NullListener

org.jikesrvm.adaptive.measurements.listeners.CallDensityListener

public final class CallDensityListener
extends NullListener

A simple listener to accumulate counts of total events and the fraction of those events that occurred at loop backedges. In effect, this provides a mechanism for estimating the call density of the program. If most yieldpoints are being taken at backedges, then call density is low.

Field Summary

Fields

Modifier and Type	Field and Description
private double	numBackedgeSamples
private double	numSamples

Constructor Summary

Constructors

Constructor and Description
CallDensityListener()

Method Summary

Modifier and Type	Method and Description
double	callDensity()
void	report() Entry point to dump what has been collected.
void	reset() Reset the listeners data structures in preparation of a new sampling window.
void	update(int whereFrom) This method is called when its time to record that a yield point has occurred.

Methods inherited from class org.jikesrvm.adaptive.measurements.listeners.Listener

activate, activateOrganizer, isActive, passivate, setOrganizer

Methods inherited from class java.lang.Object

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

Field Detail

numSamples

private double numSamples

numBackedgeSamples

private double numBackedgeSamples

Constructor Detail

CallDensityListener

public CallDensityListener()

Method Detail

update

public void update(int whereFrom)

Description copied from class: NullListener

This method is called when its time to record that a yield point has occurred.

Specified by:

update in class NullListener

Parameters:

whereFrom - Was this a yieldpoint in a PROLOGUE, BACKEDGE, or EPILOGUE?

callDensity

public double callDensity()

reset

public void reset()

Description copied from class: Listener

Reset the listeners data structures in preparation of a new sampling window. This is called by the organizer after processing the samples from the old sampling window.

Specified by:

reset in class Listener

report

public void report()

Description copied from class: Listener

Entry point to dump what has been collected.

Specified by:

report in class Listener