78 lines
4.2 KiB
JavaScript
78 lines
4.2 KiB
JavaScript
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"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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/*
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* This is a TypeScript port of the original Java version, which was written by
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* Gil Tene as described in
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* https://github.com/HdrHistogram/HdrHistogram
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* and released to the public domain, as explained at
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* http://creativecommons.org/publicdomain/zero/1.0/
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*/
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const JsHistogram_1 = require("./JsHistogram");
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const PackedArray_1 = require("./packedarray/PackedArray");
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/**
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* <h3>A High Dynamic Range (HDR) Histogram that uses a packed internal representation</h3>
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* <p>
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* {@link PackedHistogram} supports the recording and analyzing sampled data value counts across a configurable
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* integer value range with configurable value precision within the range. Value precision is expressed as the
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* number of significant digits in the value recording, and provides control over value quantization behavior
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* across the value range and the subsequent value resolution at any given level.
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* <p>
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* {@link PackedHistogram} tracks value counts in a packed internal representation optimized
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* for typical histogram recoded values are sparse in the value range and tend to be incremented in small unit counts.
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* This packed representation tends to require significantly smaller amounts of stoarge when compared to unpacked
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* representations, but can incur additional recording cost due to resizing and repacking operations that may
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* occur as previously unrecorded values are encountered.
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* <p>
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* For example, a {@link PackedHistogram} could be configured to track the counts of observed integer values between 0 and
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* 3,600,000,000,000 while maintaining a value precision of 3 significant digits across that range. Value quantization
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* within the range will thus be no larger than 1/1,000th (or 0.1%) of any value. This example Histogram could
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* be used to track and analyze the counts of observed response times ranging between 1 nanosecond and 1 hour
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* in magnitude, while maintaining a value resolution of 1 microsecond up to 1 millisecond, a resolution of
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* 1 millisecond (or better) up to one second, and a resolution of 1 second (or better) up to 1,000 seconds. At its
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* maximum tracked value (1 hour), it would still maintain a resolution of 3.6 seconds (or better).
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* <p>
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* Auto-resizing: When constructed with no specified value range range (or when auto-resize is turned on with {@link
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* Histogram#setAutoResize}) a {@link PackedHistogram} will auto-resize its dynamic range to include recorded values as
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* they are encountered. Note that recording calls that cause auto-resizing may take longer to execute, as resizing
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* incurs allocation and copying of internal data structures.
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* <p>
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*/
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class PackedHistogram extends JsHistogram_1.default {
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constructor(lowestDiscernibleValue, highestTrackableValue, numberOfSignificantValueDigits) {
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super(lowestDiscernibleValue, highestTrackableValue, numberOfSignificantValueDigits);
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this._totalCount = 0;
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this.packedCounts = new PackedArray_1.PackedArray(this.countsArrayLength);
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}
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clearCounts() {
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this.packedCounts.clear();
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}
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incrementCountAtIndex(index) {
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this.packedCounts.increment(index);
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}
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addToCountAtIndex(index, value) {
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this.packedCounts.add(index, value);
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}
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setCountAtIndex(index, value) {
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this.packedCounts.set(index, value);
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}
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resize(newHighestTrackableValue) {
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this.establishSize(newHighestTrackableValue);
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this.packedCounts.setVirtualLength(this.countsArrayLength);
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}
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getCountAtIndex(index) {
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return this.packedCounts.get(index);
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}
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_getEstimatedFootprintInBytes() {
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return 192 + 8 * this.packedCounts.getPhysicalLength();
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}
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copyCorrectedForCoordinatedOmission(expectedIntervalBetweenValueSamples) {
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const copy = new PackedHistogram(this.lowestDiscernibleValue, this.highestTrackableValue, this.numberOfSignificantValueDigits);
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copy.addWhileCorrectingForCoordinatedOmission(this, expectedIntervalBetweenValueSamples);
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return copy;
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}
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toString() {
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return `PackedHistogram ${JSON.stringify(this, null, 2)}`;
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}
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}
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exports.default = PackedHistogram;
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//# sourceMappingURL=PackedHistogram.js.map
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