public class ConcurrentHistogram extends Histogram
It is important to note that concurrent recording, auto-sizing, and value shifting are the only thread-safe
behaviors provided by ConcurrentHistogram
, and that it is not otherwise synchronized. Specifically, ConcurrentHistogram
provides no implicit synchronization that would prevent the contents of the histogram
from changing during queries, iterations, copies, or addition operations on the histogram. Callers wishing to make
potentially concurrent, multi-threaded updates that would safely work in the presence of queries, copies, or
additions of histogram objects should either take care to externally synchronize and/or order their access,
use the SynchronizedHistogram
variant, or (recommended) use Recorder
or
SingleWriterRecorder
which are intended for this purpose.
Auto-resizing: When constructed with no specified value range range (or when auto-resize is turned on with AbstractHistogram.setAutoResize(boolean)
) a Histogram
will auto-resize its dynamic range to include recorded values as
they are encountered. Note that recording calls that cause auto-resizing may take longer to execute, as resizing
incurs allocation and copying of internal data structures.
See package description for org.HdrHistogram
for details.
Modifier and Type | Class and Description |
---|---|
(package private) static class |
ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset |
AbstractHistogram.AllValues, AbstractHistogram.LinearBucketValues, AbstractHistogram.LogarithmicBucketValues, AbstractHistogram.Percentiles, AbstractHistogram.RecordedValues
Modifier and Type | Field and Description |
---|---|
(package private) ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset |
activeCounts |
(package private) ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset |
inactiveCounts |
(package private) long |
totalCount |
(package private) static java.util.concurrent.atomic.AtomicLongFieldUpdater<ConcurrentHistogram> |
totalCountUpdater |
(package private) WriterReaderPhaser |
wrp |
counts, normalizingIndexOffset
leadingZeroCountBase, maxValue, minNonZeroValue, subBucketHalfCount, subBucketHalfCountMagnitude, subBucketMask, unitMagnitude, unitMagnitudeMask
autoResize, bucketCount, constructionIdentityCount, countsArrayLength, doubleToIntegerValueConversionRatio, endTimeStampMsec, highestTrackableValue, identity, integerToDoubleValueConversionRatio, intermediateUncompressedByteArray, intermediateUncompressedByteBuffer, lowestDiscernibleValue, numberOfSignificantValueDigits, percentileIterator, recordedValuesIterator, startTimeStampMsec, subBucketCount, tag, wordSizeInBytes
Constructor and Description |
---|
ConcurrentHistogram(AbstractHistogram source)
Construct a histogram with the same range settings as a given source histogram,
duplicating the source's start/end timestamps (but NOT it's contents)
|
ConcurrentHistogram(int numberOfSignificantValueDigits)
Construct an auto-resizing ConcurrentHistogram with a lowest discernible value of 1 and an auto-adjusting
highestTrackableValue.
|
ConcurrentHistogram(long highestTrackableValue,
int numberOfSignificantValueDigits)
Construct a ConcurrentHistogram given the Highest value to be tracked and a number of significant decimal digits.
|
ConcurrentHistogram(long lowestDiscernibleValue,
long highestTrackableValue,
int numberOfSignificantValueDigits)
Construct a ConcurrentHistogram given the Lowest and Highest values to be tracked and a number of significant
decimal digits.
|
Modifier and Type | Method and Description |
---|---|
(package private) int |
_getEstimatedFootprintInBytes() |
(package private) void |
addToCountAtIndex(int index,
long value) |
(package private) void |
addToTotalCount(long value) |
(package private) void |
clearCounts() |
ConcurrentHistogram |
copy()
Create a copy of this histogram, complete with data and everything.
|
ConcurrentHistogram |
copyCorrectedForCoordinatedOmission(long expectedIntervalBetweenValueSamples)
Get a copy of this histogram, corrected for coordinated omission.
|
private void |
copyInactiveCountsContentsOnResize(ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset oldInactiveCounts,
int countsDelta) |
static ConcurrentHistogram |
decodeFromByteBuffer(java.nio.ByteBuffer buffer,
long minBarForHighestTrackableValue)
Construct a new histogram by decoding it from a ByteBuffer.
|
static ConcurrentHistogram |
decodeFromCompressedByteBuffer(java.nio.ByteBuffer buffer,
long minBarForHighestTrackableValue)
Construct a new histogram by decoding it from a compressed form in a ByteBuffer.
|
(package private) void |
fillBufferFromCountsArray(java.nio.ByteBuffer buffer) |
(package private) void |
fillCountsArrayFromBuffer(java.nio.ByteBuffer buffer,
int length) |
(package private) long |
getCountAtIndex(int index) |
(package private) long |
getCountAtNormalizedIndex(int index) |
(package private) int |
getNormalizingIndexOffset() |
long |
getTotalCount()
Get the total count of all recorded values in the histogram
|
(package private) void |
incrementCountAtIndex(int index) |
(package private) void |
incrementTotalCount() |
private void |
readObject(java.io.ObjectInputStream o) |
(package private) void |
recordConvertedDoubleValue(double value) |
void |
recordConvertedDoubleValueWithCount(double value,
long count) |
(package private) void |
resize(long newHighestTrackableValue) |
void |
setAutoResize(boolean autoResize)
Control whether or not the histogram can auto-resize and auto-adjust it's
highestTrackableValue
|
(package private) void |
setCountAtIndex(int index,
long value) |
(package private) void |
setCountAtNormalizedIndex(int index,
long value) |
(package private) void |
setIntegerToDoubleValueConversionRatio(double integerToDoubleValueConversionRatio) |
(package private) void |
setNormalizingIndexOffset(int normalizingIndexOffset) |
private void |
setNormalizingIndexOffset(int normalizingIndexOffset,
int shiftedAmount,
boolean lowestHalfBucketPopulated,
double newIntegerToDoubleValueConversionRatio) |
(package private) void |
setTotalCount(long totalCount) |
private void |
shiftLowestInactiveHalfBucketContentsLeft(int shiftAmount,
int preShiftZeroIndex) |
(package private) void |
shiftNormalizingIndexByOffset(int offsetToAdd,
boolean lowestHalfBucketPopulated,
double newIntegerToDoubleValueConversionRatio) |
add, addWhileCorrectingForCoordinatedOmission, allValues, copyInto, copyIntoCorrectedForCoordinatedOmission, countsArrayIndex, decodeFromByteBuffer, decodeFromCompressedByteBuffer, determineArrayLengthNeeded, encodeIntoByteBuffer, encodeIntoCompressedByteBuffer, encodeIntoCompressedByteBuffer, equals, establishInternalTackingValues, establishInternalTackingValues, establishSize, getBucketIndex, getBucketsNeededToCoverValue, getCountAtValue, getCountBetweenValues, getEndTimeStamp, getEstimatedFootprintInBytes, getHighestTrackableValue, getLengthForNumberOfBuckets, getLowestDiscernibleValue, getMaxValue, getMaxValueAsDouble, getMean, getMinNonZeroValue, getMinValue, getNeededByteBufferCapacity, getNeededByteBufferCapacity, getNeededPayloadByteBufferCapacity, getNeededV0PayloadByteBufferCapacity, getNumberOfSignificantValueDigits, getPercentileAtOrBelowValue, getStartTimeStamp, getStdDeviation, getSubBucketIndex, getTag, getValueAtPercentile, hashCode, highestEquivalentValue, isAutoResize, linearBucketValues, logarithmicBucketValues, lowestEquivalentValue, medianEquivalentValue, nextNonEquivalentValue, nonConcurrentNormalizingIndexShift, normalizeIndex, numberOfSubbuckets, outputPercentileDistribution, outputPercentileDistribution, outputPercentileDistribution, percentiles, recordedValues, recordValue, recordValue, recordValueWithCount, recordValueWithExpectedInterval, reset, setEndTimeStamp, setStartTimeStamp, setTag, shiftValuesLeft, shiftValuesLeft, shiftValuesRight, shiftValuesRight, sizeOfEquivalentValueRange, subtract, supportsAutoResize, updateMinAndMax, valueFromIndex, valuesAreEquivalent
getDoubleToIntegerValueConversionRatio, getIntegerToDoubleValueConversionRatio, nonConcurrentSetIntegerToDoubleValueConversionRatio
static final java.util.concurrent.atomic.AtomicLongFieldUpdater<ConcurrentHistogram> totalCountUpdater
volatile long totalCount
volatile ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset activeCounts
volatile ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset inactiveCounts
transient WriterReaderPhaser wrp
public ConcurrentHistogram(int numberOfSignificantValueDigits)
numberOfSignificantValueDigits
- Specifies the precision to use. This is the number of significant
decimal digits to which the histogram will maintain value resolution
and separation. Must be a non-negative integer between 0 and 5.public ConcurrentHistogram(long highestTrackableValue, int numberOfSignificantValueDigits)
highestTrackableValue
- The highest value to be tracked by the histogram. Must be a positive
integer that is >= 2.numberOfSignificantValueDigits
- Specifies the precision to use. This is the number of significant
decimal digits to which the histogram will maintain value resolution
and separation. Must be a non-negative integer between 0 and 5.public ConcurrentHistogram(long lowestDiscernibleValue, long highestTrackableValue, int numberOfSignificantValueDigits)
lowestDiscernibleValue
- The lowest value that can be tracked (distinguished from 0) by the histogram.
Must be a positive integer that is >= 1. May be internally rounded
down to nearest power of 2.highestTrackableValue
- The highest value to be tracked by the histogram. Must be a positive
integer that is >= (2 * lowestDiscernibleValue).numberOfSignificantValueDigits
- Specifies the precision to use. This is the number of significant
decimal digits to which the histogram will maintain value resolution
and separation. Must be a non-negative integer between 0 and 5.public ConcurrentHistogram(AbstractHistogram source)
source
- The source histogram to duplicatevoid setIntegerToDoubleValueConversionRatio(double integerToDoubleValueConversionRatio)
setIntegerToDoubleValueConversionRatio
in class Histogram
long getCountAtIndex(int index)
getCountAtIndex
in class Histogram
long getCountAtNormalizedIndex(int index)
getCountAtNormalizedIndex
in class Histogram
void incrementCountAtIndex(int index)
incrementCountAtIndex
in class Histogram
void addToCountAtIndex(int index, long value)
addToCountAtIndex
in class Histogram
void setCountAtIndex(int index, long value)
setCountAtIndex
in class Histogram
void setCountAtNormalizedIndex(int index, long value)
setCountAtNormalizedIndex
in class Histogram
void recordConvertedDoubleValue(double value)
recordConvertedDoubleValue
in class AbstractHistogram
public void recordConvertedDoubleValueWithCount(double value, long count) throws java.lang.ArrayIndexOutOfBoundsException
recordConvertedDoubleValueWithCount
in class AbstractHistogram
java.lang.ArrayIndexOutOfBoundsException
int getNormalizingIndexOffset()
getNormalizingIndexOffset
in class Histogram
void setNormalizingIndexOffset(int normalizingIndexOffset)
setNormalizingIndexOffset
in class Histogram
private void setNormalizingIndexOffset(int normalizingIndexOffset, int shiftedAmount, boolean lowestHalfBucketPopulated, double newIntegerToDoubleValueConversionRatio)
private void shiftLowestInactiveHalfBucketContentsLeft(int shiftAmount, int preShiftZeroIndex)
void shiftNormalizingIndexByOffset(int offsetToAdd, boolean lowestHalfBucketPopulated, double newIntegerToDoubleValueConversionRatio)
shiftNormalizingIndexByOffset
in class Histogram
private void copyInactiveCountsContentsOnResize(ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset oldInactiveCounts, int countsDelta)
public void setAutoResize(boolean autoResize)
AbstractHistogram
setAutoResize
in class AbstractHistogram
autoResize
- autoResize settingvoid clearCounts()
clearCounts
in class Histogram
public ConcurrentHistogram copy()
AbstractHistogram
public ConcurrentHistogram copyCorrectedForCoordinatedOmission(long expectedIntervalBetweenValueSamples)
AbstractHistogram
To compensate for the loss of sampled values when a recorded value is larger than the expected
interval between value samples, the new histogram will include an auto-generated additional series of
decreasingly-smaller (down to the expectedIntervalBetweenValueSamples) value records for each count found
in the current histogram that is larger than the expectedIntervalBetweenValueSamples.
Note: This is a post-correction method, as opposed to the at-recording correction method provided
by recordValueWithExpectedInterval
. The two
methods are mutually exclusive, and only one of the two should be be used on a given data set to correct
for the same coordinated omission issue.
by
See notes in the description of the Histogram calls for an illustration of why this corrective behavior is important.
copyCorrectedForCoordinatedOmission
in class Histogram
expectedIntervalBetweenValueSamples
- If expectedIntervalBetweenValueSamples is larger than 0, add
auto-generated value records as appropriate if value is larger
than expectedIntervalBetweenValueSamplespublic long getTotalCount()
AbstractHistogram
getTotalCount
in class Histogram
void setTotalCount(long totalCount)
setTotalCount
in class Histogram
void incrementTotalCount()
incrementTotalCount
in class Histogram
void addToTotalCount(long value)
addToTotalCount
in class Histogram
int _getEstimatedFootprintInBytes()
_getEstimatedFootprintInBytes
in class Histogram
public static ConcurrentHistogram decodeFromByteBuffer(java.nio.ByteBuffer buffer, long minBarForHighestTrackableValue)
buffer
- The buffer to decode fromminBarForHighestTrackableValue
- Force highestTrackableValue to be set at least this highpublic static ConcurrentHistogram decodeFromCompressedByteBuffer(java.nio.ByteBuffer buffer, long minBarForHighestTrackableValue) throws java.util.zip.DataFormatException
buffer
- The buffer to decode fromminBarForHighestTrackableValue
- Force highestTrackableValue to be set at least this highjava.util.zip.DataFormatException
- on error parsing/decompressing the bufferprivate void readObject(java.io.ObjectInputStream o) throws java.io.IOException, java.lang.ClassNotFoundException
java.io.IOException
java.lang.ClassNotFoundException
void fillCountsArrayFromBuffer(java.nio.ByteBuffer buffer, int length)
fillCountsArrayFromBuffer
in class Histogram
void fillBufferFromCountsArray(java.nio.ByteBuffer buffer)
fillBufferFromCountsArray
in class AbstractHistogram