com.sleepycat.je.utilint

Class LatencyPercentileStat

java.lang.Object

com.sleepycat.je.utilint.BaseStat<T>

com.sleepycat.je.utilint.Stat<T>

com.sleepycat.je.utilint.StatWithValueType<Long>

com.sleepycat.je.utilint.LatencyPercentileStat

All Implemented Interfaces:

Serializable, Cloneable

public class LatencyPercentileStat
extends StatWithValueType<Long>

An long JE stat that computes a percentile latency by tracking latency values in milliseconds. The percentile value represents the smallest latency value for which no more than the specified percentage of the observed values were strictly less than the value and at least the specified percentage of the values were less than or equal to that value. To save space, specific values are recorded only below a specified value, so all larger values are lumped together and reported as the maximum value. Returns zero if no values are observed.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_MAX_TRACKED_LATENCY_MILLIS The default maximum value for tracking latency values.

Fields inherited from class com.sleepycat.je.utilint.Stat

definition

Constructor Summary

Constructors

Constructor and Description
LatencyPercentileStat(StatGroup group, StatDefinition definition, float percentile) Creates an instance of this class using the default maximum for tracking latency values of 1000.
LatencyPercentileStat(StatGroup group, StatDefinition definition, float percentile, int maxTrackedLatencyMillis) Creates an instance of this class.

Method Summary

Modifier and Type	Method and Description
void	add(long latencyMillis) Record a single operation that the specified amount of time in milliseconds.
void	add(Stat<Long> other) Add the value of "other" to this stat.
void	clear() Resets the statistic to its initial state.
LatencyPercentileStat	computeInterval(Stat<Long> base) Compute interval value with respect to the base value.
LatencyPercentileStat	copy() Returns a copy of this statistic.
Long	get() Returns the value of the statistic.
String	getFormattedValue() Returns the value of the statistic as a formatted string.
Class<Long>	getValueType() Returns the type of the value returned by the BaseStat.get() method.
boolean	isNotSet() Returns whether the statistic is in its initial state.
void	negate() Negate the value.
void	set(Long newValue) Set the stat value.

Methods inherited from class com.sleepycat.je.utilint.StatWithValueType

getForType

Methods inherited from class com.sleepycat.je.utilint.Stat

copyAndAdd, copyAndClear, getDefinition, toString, toStringVerbose

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MAX_TRACKED_LATENCY_MILLIS

public static final int DEFAULT_MAX_TRACKED_LATENCY_MILLIS

The default maximum value for tracking latency values.

See Also:

Constant Field Values

Constructor Detail

LatencyPercentileStat

public LatencyPercentileStat(StatGroup group,
                             StatDefinition definition,
                             float percentile)

Creates an instance of this class using the default maximum for tracking latency values of 1000. The definition type must be INCREMENTAL.

Parameters:

percentile - the percentile latency to report as a ratio between 0.0 and 1.0

Throws:

IllegalArgumentException - if the stat definition type is not INCREMENTAL, the percentile is less than 0.0 or greater than 1.0, or maxTrackedLatencyMillis is less than 0

LatencyPercentileStat

public LatencyPercentileStat(StatGroup group,
                             StatDefinition definition,
                             float percentile,
                             int maxTrackedLatencyMillis)

Creates an instance of this class. The definition type must be INCREMENTAL.

Parameters:

percentile - the percentile latency to report as a ratio between 0.0 and 1.0

maxTrackedLatencyMillis - the maximum for tracking latency values

Throws:

IllegalArgumentException - if the stat definition type is not INCREMENTAL, the percentile is less than 0.0 or greater than 1.0, or maxTrackedLatencyMillis is less than 0

Method Detail

add

public void add(long latencyMillis)

Record a single operation that the specified amount of time in milliseconds.

getValueType

public Class<Long> getValueType()

Description copied from class: StatWithValueType

Returns the type of the value returned by the BaseStat.get() method.

Specified by:

getValueType in class StatWithValueType<Long>

Returns:

the type of the value returned by get

set

public void set(Long newValue)

Set the stat value.

Specified by:

set in class Stat<Long>

Throws:

UnsupportedOperationException - always

add

public void add(Stat<Long> other)

Add the value of "other" to this stat.

Specified by:

add in class Stat<Long>

Throws:

IllegalArgumentException - if argument is not a LatencyPercentileStat or if it has a different maximum latency

computeInterval

public LatencyPercentileStat computeInterval(Stat<Long> base)

Compute interval value with respect to the base value.

Specified by:

computeInterval in class Stat<Long>

Throws:

IllegalArgumentException - if argument is not a LatencyPercentileStat or if it has a different maximum latency

negate

public void negate()

Description copied from class: Stat

Negate the value.

Specified by:

negate in class Stat<Long>

get

public Long get()

Description copied from class: BaseStat

Returns the value of the statistic.

Specified by:

get in class BaseStat<Long>

Returns:

the value

clear

public void clear()

Description copied from class: BaseStat

Resets the statistic to its initial state.

Specified by:

clear in class BaseStat<Long>

copy

public LatencyPercentileStat copy()

Description copied from class: BaseStat

Returns a copy of this statistic.

Overrides:

copy in class Stat<Long>

Returns:

a copy

getFormattedValue

public String getFormattedValue()

Description copied from class: BaseStat

Returns the value of the statistic as a formatted string.

Specified by:

getFormattedValue in class BaseStat<Long>

Returns:

the value as a formatted string

isNotSet

public boolean isNotSet()

Description copied from class: BaseStat

Returns whether the statistic is in its initial state.

Specified by:

isNotSet in class BaseStat<Long>

Returns:

if the statistic is in its initial state