Package fr.dyade.aaa.common

Class AverageLoadTask

java.lang.Object

java.util.TimerTask

fr.dyade.aaa.common.AverageLoadTask

All Implemented Interfaces:

Runnable

Direct Known Subclasses:

Engine.EngineAverageLoadTask, Network.NetworkAverageLoadTask

public abstract class AverageLoadTask
extends TimerTask

This class computes the load average of the server using Unix algorithm. This task needs to be scheduled every 5 seconds.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) long	averageLoad1	load averages for the last minute.
(package private) long	averageLoad15	load averages for the past 15 minutes.
(package private) long	averageLoad5	load averages for the past 5 minutes.
private static long	EXP_1	1/exp(5sec/1min) as fixed-point
private static long	EXP_15	1/exp(5sec/15min)
private static long	EXP_5	1/exp(5sec/5min)
private static long	FIXED_1	1.0 as fixed-point
private static long	FSHIFT	number of bits of precision

Constructor Summary

Constructors

Constructor	Description
AverageLoadTask()

Method Summary

Modifier and Type	Method	Description
(package private) long	computeLoad(long load, long exp, long n)
(package private) float	convert(long average)
protected abstract long	countActiveTasks()
float	getAverageLoad1()	Returns the load averages for the last minute.
float	getAverageLoad15()	Returns the load averages for the past 15 minutes.
float	getAverageLoad5()	Returns the load averages for the past 5 minutes.
void	reset()
void	run()
protected void	start(Timer timer)	Starts the resulting task.

Methods inherited from class java.util.TimerTask

cancel, scheduledExecutionTime

Methods inherited from class java.lang.Object

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

Field Detail

FSHIFT

private static final long FSHIFT

number of bits of precision

See Also:

Constant Field Values

FIXED_1

private static final long FIXED_1

1.0 as fixed-point

See Also:

Constant Field Values

EXP_1

private static final long EXP_1

1/exp(5sec/1min) as fixed-point

See Also:

Constant Field Values

EXP_5

private static final long EXP_5

1/exp(5sec/5min)

See Also:

Constant Field Values

EXP_15

private static final long EXP_15

1/exp(5sec/15min)

See Also:

Constant Field Values

averageLoad1

long averageLoad1

load averages for the last minute.

averageLoad5

long averageLoad5

load averages for the past 5 minutes.

averageLoad15

long averageLoad15

load averages for the past 15 minutes.

Constructor Detail

AverageLoadTask

public AverageLoadTask()

Method Detail

getAverageLoad1

public float getAverageLoad1()

Returns the load averages for the last minute.

Returns:

the load averages for the last minute.

getAverageLoad5

public float getAverageLoad5()

Returns the load averages for the past 5 minutes.

Returns:

the load averages for the past 5 minutes.

getAverageLoad15

public float getAverageLoad15()

Returns the load averages for the past 15 minutes.

Returns:

the load averages for the past 15 minutes.

convert

float convert(long average)

computeLoad

long computeLoad(long load,
                 long exp,
                 long n)

countActiveTasks

protected abstract long countActiveTasks()

run

public void run()

Specified by:

run in interface Runnable

Specified by:

run in class TimerTask

See Also:

TimerTask.run()

reset

public void reset()

start

protected final void start(Timer timer)

Starts the resulting task.

Parameters:

timer - Timer to use to schedule the resulting task.