org.apache.jmeter.monitor.util
Class Stats

java.lang.Object
  org.apache.jmeter.monitor.util.Stats

public class Stats
extends Object

Description:

Stats is responsible for calculating the load and health of a given server. It uses tomcat's status servlet results. A schema was generated for the XML output and JAXB was used to generate classes.

The equations are:

memory weight = (int)(50 * (free/max))
thread weight = (int)(50 * (current/max))

The load factors are stored in the properties files. Simply change the values in the properties to change how load is calculated. The defaults values are memory (50) and threads (50). The sum of the factors must equal 100.

Field Summary

static int	ACTIVE
static double	ACTIVE_PER
static int	DEAD
static int	DEFAULT_MEMORY_FACTOR
static int	DEFAULT_THREAD_FACTOR
static int	HEALTHY
static double	HEALTHY_PER
static int	WARNING
static double	WARNING_PER

Constructor Summary

Stats()

Method Summary

static int	calculateLoad(Status stat) The method is responsible for taking a status object and calculating an int value from 1 to 100.
static int	calculateMemoryLoad(Status stat) Method will calculate the memory load: used / max = load.
static int	calculateStatus(Status stat) Method should calculate if the server is: dead, active, warning or healthy.
static int	calculateThreadLoad(Status stat) Method will calculate the thread load: busy / max = load.

Methods inherited from class java.lang.Object

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

Field Detail

DEAD

public static final int DEAD

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Constant Field Values

ACTIVE

public static final int ACTIVE

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Constant Field Values

WARNING

public static final int WARNING

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Constant Field Values

HEALTHY

public static final int HEALTHY

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Constant Field Values

DEFAULT_MEMORY_FACTOR

public static final int DEFAULT_MEMORY_FACTOR

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Constant Field Values

DEFAULT_THREAD_FACTOR

public static final int DEFAULT_THREAD_FACTOR

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Constant Field Values

HEALTHY_PER

public static final double HEALTHY_PER

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Constant Field Values

ACTIVE_PER

public static final double ACTIVE_PER

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Constant Field Values

WARNING_PER

public static final double WARNING_PER

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Constant Field Values

Constructor Detail

Stats

public Stats()

Method Detail

calculateLoad

public static int calculateLoad(Status stat)

The method is responsible for taking a status object and calculating an int value from 1 to 100. We use a combination of free memory and free threads. The current factor is 50/50.

Parameters:

stat -

Returns:

calculated load value

calculateStatus

public static int calculateStatus(Status stat)

Method should calculate if the server is: dead, active, warning or healthy. We do this by looking at the current busy threads.

1. free > spare is healthy
2. free < spare is active
3. busy threads > 75% is warning
4. none of the above is dead

Parameters:

stat -

Returns:

integer representing the status

calculateMemoryLoad

public static int calculateMemoryLoad(Status stat)

Method will calculate the memory load: used / max = load. The load value is an integer between 1 and 100. It is the percent memory used. Changed this to be more like other system monitors. Peter Lin 2-11-05

Parameters:

stat -

Returns:

memory load

calculateThreadLoad

public static int calculateThreadLoad(Status stat)

Method will calculate the thread load: busy / max = load. The value is an integer between 1 and 100. It is the percent busy.

Parameters:

stat -

Returns:

thread load