Class PackedConcurrentHistogram
- java.lang.Object
-
- org.HdrHistogram.EncodableHistogram
-
- org.HdrHistogram.AbstractHistogramBase
-
- org.HdrHistogram.AbstractHistogram
-
- org.HdrHistogram.Histogram
-
- org.HdrHistogram.ConcurrentHistogram
-
- org.HdrHistogram.PackedConcurrentHistogram
-
- All Implemented Interfaces:
java.io.Serializable
,ValueRecorder
- Direct Known Subclasses:
Recorder.InternalPackedConcurrentHistogram
public class PackedConcurrentHistogram extends ConcurrentHistogram
An integer values High Dynamic Range (HDR) Histogram that uses a packed internal representation and supports safe concurrent recording operations.
APackedConcurrentHistogram
guarantees lossless recording of values into the histogram even when the histogram is updated by multiple threads, and supports auto-resize and shift operations that may result from or occur concurrently with other recording operations.PackedConcurrentHistogram
tracks value counts in a packed internal representation optimized for typical histogram recoded values are sparse in the value range and tend to be incremented in small unit counts. This packed representation tends to require significantly smaller amounts of stoarge when compared to unpacked representations, but can incur additional recording cost due to resizing and repacking operations that may occur as previously unrecorded values are encountered.It is important to note that concurrent recording, auto-sizing, and value shifting are the only thread-safe behaviors provided by
PackedConcurrentHistogram
, and that it is not otherwise synchronized. Specifically,PackedConcurrentHistogram
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, useRecorder
orSingleWriterRecorder
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)
) aPackedConcurrentHistogram
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.- See Also:
- Serialized Form
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description (package private) static class
PackedConcurrentHistogram.ConcurrentPackedArrayWithNormalizingOffset
-
Nested classes/interfaces inherited from class org.HdrHistogram.ConcurrentHistogram
ConcurrentHistogram.AtomicLongArrayWithNormalizingOffset, ConcurrentHistogram.ConcurrentArrayWithNormalizingOffset
-
Nested classes/interfaces inherited from class org.HdrHistogram.AbstractHistogram
AbstractHistogram.AllValues, AbstractHistogram.LinearBucketValues, AbstractHistogram.LogarithmicBucketValues, AbstractHistogram.Percentiles, AbstractHistogram.RecordedValues
-
-
Field Summary
-
Fields inherited from class org.HdrHistogram.ConcurrentHistogram
activeCounts, inactiveCounts, totalCount, totalCountUpdater, wrp
-
Fields inherited from class org.HdrHistogram.Histogram
counts, normalizingIndexOffset
-
Fields inherited from class org.HdrHistogram.AbstractHistogram
leadingZeroCountBase, maxValue, minNonZeroValue, subBucketHalfCount, subBucketHalfCountMagnitude, subBucketMask, unitMagnitude, unitMagnitudeMask
-
Fields inherited from class org.HdrHistogram.AbstractHistogramBase
autoResize, bucketCount, constructionIdentityCount, countsArrayLength, doubleToIntegerValueConversionRatio, endTimeStampMsec, highestTrackableValue, identity, integerToDoubleValueConversionRatio, intermediateUncompressedByteArray, intermediateUncompressedByteBuffer, lowestDiscernibleValue, numberOfSignificantValueDigits, percentileIterator, recordedValuesIterator, startTimeStampMsec, subBucketCount, tag, wordSizeInBytes
-
-
Constructor Summary
Constructors Constructor Description PackedConcurrentHistogram(int numberOfSignificantValueDigits)
Construct an auto-resizing ConcurrentHistogram with a lowest discernible value of 1 and an auto-adjusting highestTrackableValue.PackedConcurrentHistogram(long highestTrackableValue, int numberOfSignificantValueDigits)
Construct a ConcurrentHistogram given the Highest value to be tracked and a number of significant decimal digits.PackedConcurrentHistogram(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.PackedConcurrentHistogram(long lowestDiscernibleValue, long highestTrackableValue, int numberOfSignificantValueDigits, boolean allocateCountsArray)
PackedConcurrentHistogram(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)PackedConcurrentHistogram(AbstractHistogram source, boolean allocateCountsArray)
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description (package private) int
_getEstimatedFootprintInBytes()
(package private) void
addToTotalCount(long value)
(package private) ConcurrentHistogram.ConcurrentArrayWithNormalizingOffset
allocateArray(int length, int normalizingIndexOffset)
(package private) void
clearCounts()
PackedConcurrentHistogram
copy()
Create a copy of this histogram, complete with data and everything.PackedConcurrentHistogram
copyCorrectedForCoordinatedOmission(long expectedIntervalBetweenValueSamples)
Get a copy of this histogram, corrected for coordinated omission.static PackedConcurrentHistogram
decodeFromByteBuffer(java.nio.ByteBuffer buffer, long minBarForHighestTrackableValue)
Construct a new histogram by decoding it from a ByteBuffer.static PackedConcurrentHistogram
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)
static PackedConcurrentHistogram
fromString(java.lang.String base64CompressedHistogramString)
Construct a new ConcurrentHistogram by decoding it from a String containing a base64 encoded compressed histogram representation.long
getTotalCount()
Get the total count of all recorded values in the histogram(package private) void
incrementTotalCount()
private void
readObject(java.io.ObjectInputStream o)
(package private) void
setTotalCount(long totalCount)
-
Methods inherited from class org.HdrHistogram.ConcurrentHistogram
addToCountAtIndex, copyInactiveCountsContentsOnResize, getCountAtIndex, getCountAtNormalizedIndex, getNormalizingIndexOffset, incrementCountAtIndex, recordConvertedDoubleValue, recordConvertedDoubleValueWithCount, resize, setAutoResize, setCountAtIndex, setCountAtNormalizedIndex, setIntegerToDoubleValueConversionRatio, setNormalizingIndexOffset, shiftNormalizingIndexByOffset
-
Methods inherited from class org.HdrHistogram.AbstractHistogram
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, toString, updateMinAndMax, valueFromIndex, valuesAreEquivalent
-
Methods inherited from class org.HdrHistogram.AbstractHistogramBase
getDoubleToIntegerValueConversionRatio, getIntegerToDoubleValueConversionRatio, nonConcurrentSetIntegerToDoubleValueConversionRatio
-
-
-
-
Constructor Detail
-
PackedConcurrentHistogram
public PackedConcurrentHistogram(int numberOfSignificantValueDigits)
Construct an auto-resizing ConcurrentHistogram with a lowest discernible value of 1 and an auto-adjusting highestTrackableValue. Can auto-resize up to track values up to (Long.MAX_VALUE / 2).- Parameters:
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.
-
PackedConcurrentHistogram
public PackedConcurrentHistogram(long highestTrackableValue, int numberOfSignificantValueDigits)
Construct a ConcurrentHistogram given the Highest value to be tracked and a number of significant decimal digits. The histogram will be constructed to implicitly track (distinguish from 0) values as low as 1.- Parameters:
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.
-
PackedConcurrentHistogram
public PackedConcurrentHistogram(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. Providing a lowestDiscernibleValue is useful is situations where the units used for the histogram's values are much smaller that the minimal accuracy required. E.g. when tracking time values stated in nanosecond units, where the minimal accuracy required is a microsecond, the proper value for lowestDiscernibleValue would be 1000.- Parameters:
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.
-
PackedConcurrentHistogram
public PackedConcurrentHistogram(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)- Parameters:
source
- The source histogram to duplicate
-
PackedConcurrentHistogram
PackedConcurrentHistogram(AbstractHistogram source, boolean allocateCountsArray)
-
PackedConcurrentHistogram
PackedConcurrentHistogram(long lowestDiscernibleValue, long highestTrackableValue, int numberOfSignificantValueDigits, boolean allocateCountsArray)
-
-
Method Detail
-
allocateArray
ConcurrentHistogram.ConcurrentArrayWithNormalizingOffset allocateArray(int length, int normalizingIndexOffset)
- Overrides:
allocateArray
in classConcurrentHistogram
-
clearCounts
void clearCounts()
- Overrides:
clearCounts
in classConcurrentHistogram
-
copy
public PackedConcurrentHistogram copy()
Description copied from class:AbstractHistogram
Create a copy of this histogram, complete with data and everything.- Overrides:
copy
in classConcurrentHistogram
- Returns:
- A distinct copy of this histogram.
-
copyCorrectedForCoordinatedOmission
public PackedConcurrentHistogram copyCorrectedForCoordinatedOmission(long expectedIntervalBetweenValueSamples)
Description copied from class:AbstractHistogram
Get a copy of this histogram, corrected for coordinated omission.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. bySee notes in the description of the Histogram calls for an illustration of why this corrective behavior is important.
- Overrides:
copyCorrectedForCoordinatedOmission
in classConcurrentHistogram
- Parameters:
expectedIntervalBetweenValueSamples
- If expectedIntervalBetweenValueSamples is larger than 0, add auto-generated value records as appropriate if value is larger than expectedIntervalBetweenValueSamples- Returns:
- a copy of this histogram, corrected for coordinated omission.
-
getTotalCount
public long getTotalCount()
Description copied from class:AbstractHistogram
Get the total count of all recorded values in the histogram- Overrides:
getTotalCount
in classConcurrentHistogram
- Returns:
- the total count of all recorded values in the histogram
-
setTotalCount
void setTotalCount(long totalCount)
- Overrides:
setTotalCount
in classConcurrentHistogram
-
incrementTotalCount
void incrementTotalCount()
- Overrides:
incrementTotalCount
in classConcurrentHistogram
-
addToTotalCount
void addToTotalCount(long value)
- Overrides:
addToTotalCount
in classConcurrentHistogram
-
_getEstimatedFootprintInBytes
int _getEstimatedFootprintInBytes()
- Overrides:
_getEstimatedFootprintInBytes
in classConcurrentHistogram
-
decodeFromByteBuffer
public static PackedConcurrentHistogram decodeFromByteBuffer(java.nio.ByteBuffer buffer, long minBarForHighestTrackableValue)
Construct a new histogram by decoding it from a ByteBuffer.- Parameters:
buffer
- The buffer to decode fromminBarForHighestTrackableValue
- Force highestTrackableValue to be set at least this high- Returns:
- The newly constructed histogram
-
decodeFromCompressedByteBuffer
public static PackedConcurrentHistogram decodeFromCompressedByteBuffer(java.nio.ByteBuffer buffer, long minBarForHighestTrackableValue) throws java.util.zip.DataFormatException
Construct a new histogram by decoding it from a compressed form in a ByteBuffer.- Parameters:
buffer
- The buffer to decode fromminBarForHighestTrackableValue
- Force highestTrackableValue to be set at least this high- Returns:
- The newly constructed histogram
- Throws:
java.util.zip.DataFormatException
- on error parsing/decompressing the buffer
-
fromString
public static PackedConcurrentHistogram fromString(java.lang.String base64CompressedHistogramString) throws java.util.zip.DataFormatException
Construct a new ConcurrentHistogram by decoding it from a String containing a base64 encoded compressed histogram representation.- Parameters:
base64CompressedHistogramString
- A string containing a base64 encoding of a compressed histogram- Returns:
- A ConcurrentHistogram decoded from the string
- Throws:
java.util.zip.DataFormatException
- on error parsing/decompressing the input
-
readObject
private void readObject(java.io.ObjectInputStream o) throws java.io.IOException, java.lang.ClassNotFoundException
- Throws:
java.io.IOException
java.lang.ClassNotFoundException
-
fillBufferFromCountsArray
void fillBufferFromCountsArray(java.nio.ByteBuffer buffer)
- Overrides:
fillBufferFromCountsArray
in classConcurrentHistogram
-
-