Package org.apache.hadoop.hbase.metrics.impl

Class HistogramImpl

java.lang.Object

org.apache.hadoop.hbase.metrics.impl.HistogramImpl

All Implemented Interfaces:

Histogram, Metric

@Private
public class HistogramImpl
extends Object
implements Histogram

Custom histogram implementation based on FastLongHistogram. Dropwizard-based histograms are slow compared to this implementation, so we are using our implementation here. See HBASE-15222.

Field Summary

Fields

Modifier and Type	Field	Description
private final CounterImpl	counter
protected final FastLongHistogram	histogram

Constructor Summary

Constructors

Modifier	Constructor	Description
	HistogramImpl()
	HistogramImpl(int numBins, long min, long maxExpected)
	HistogramImpl(long maxExpected)
protected	HistogramImpl(CounterImpl counter, FastLongHistogram histogram)

Method Summary

Modifier and Type	Method	Description
long	getCount()	Return the total number of values added to the histogram.
long	getMax()
long	getMin()
long[]	getQuantiles(double[] quantiles)
Snapshot	snapshot()	Snapshot the current values in the Histogram
void	update(int value)	Adds a new value to the distribution.
void	update(long value)	Adds a new value to the distribution.

Methods inherited from class java.lang.Object

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

Field Details

histogram

protected final FastLongHistogram histogram

counter

private final CounterImpl counter

Constructor Details

HistogramImpl

public HistogramImpl()

HistogramImpl

public HistogramImpl(long maxExpected)

HistogramImpl

public HistogramImpl(int numBins,
 long min,
 long maxExpected)

HistogramImpl

protected HistogramImpl(CounterImpl counter,
 FastLongHistogram histogram)

Method Details

update

public void update(int value)

Description copied from interface: Histogram

Adds a new value to the distribution.

Specified by:

update in interface Histogram

Parameters:

value - The value to add

update

public void update(long value)

Description copied from interface: Histogram

Adds a new value to the distribution.

Specified by:

update in interface Histogram

Parameters:

value - The value to add

getCount

public long getCount()

Description copied from interface: Histogram

Return the total number of values added to the histogram.

Specified by:

getCount in interface Histogram

Returns:

the total number of values.

getMax

public long getMax()

getMin

public long getMin()

snapshot

public Snapshot snapshot()

Description copied from interface: Histogram

Snapshot the current values in the Histogram

Specified by:

snapshot in interface Histogram

Returns:

a Snapshot of the distribution.

getQuantiles

public long[] getQuantiles(double[] quantiles)