2.4x improvement in Cluster aggregation performance

.gitignore

@@ -1,7 +1,10 @@
 .DS_Store
-node_modules
 .idea/
-*.log
-coverage/
+
+node_modules
+coverage
+output
+
 package-lock.json
 *.heapsnapshot
+*.log

CHANGELOG.md

@@ -31,6 +31,7 @@ project adheres to [Semantic Versioning](http://semver.org/).
 - ci: switch out deprecated benchmark-regression library for replacement
 - AggregatorRegistry renamed to ClusterRegistry, old name deprecated
 - chore: update faceoff to 1.1
+- perf: Stat aggregation uses similar strategy to collection. 60% faster aggregation
 
 ### Added
 

benchmarks/util.js

@@ -5,7 +5,7 @@ const Path = require('path');
 module.exports = setupUtilSuite;
 
 function setupUtilSuite(suite) {
-	const skip = ['prom-client@latest', 'prom-client@trunk'];
+	const skip = ['prom-client@latest'];
 
 	suite.add(
 		'hashObject',
@@ -14,6 +14,9 @@ function setupUtilSuite(suite) {
 				foo: 'longish',
 				user_agent: 'Chrome',
 				gateway: 'lb04',
+				method: 'get',
+				status_code: 200,
+				phase: 'load',
 			});
 		},
 		{ setup: findUtil, skip },
@@ -23,9 +26,13 @@ function setupUtilSuite(suite) {
 		'LabelMap.validate()',
 		(client, labelMap) => {
 			labelMap.validate({
-				foo: 'longish:tag:goes:here',
+				foo: 'longish',
 				user_agent: 'Chrome',
-				status_code: 503,
+				gateway: 'lb04',
+				method: 'get',
+				status_code: 200,
+				phase: 'load',
+				label1: 4,
 			});
 		},
 		{ setup, skip },
@@ -37,11 +44,42 @@ function setupUtilSuite(suite) {
 			labelMap.keyFrom({
 				foo: 'longish',
 				user_agent: 'Chrome',
-				status_code: 503,
+				gateway: 'lb04',
+				method: 'get',
+				status_code: 301,
+				phase: 'load',
+				label1: 4,
 			});
 		},
 		{ setup, skip },
 	);
+
+	suite.add(
+		'LabelGrouper.keyFrom()',
+		(client, labelGrouper) => {
+			if (labelGrouper === undefined) {
+				return;
+			}
+
+			labelGrouper.keyFrom({
+				foo: 'longish',
+				user_agent: 'Chrome',
+				gateway: 'lb04',
+				method: 'get',
+				status_code: 503,
+				phase: 'load',
+				label1: 4,
+			});
+		},
+		{
+			setup: (client, location) => {
+				const Util = findUtil(client, location);
+
+				return new Util.LabelGrouper();
+			},
+			skip: ['prom-client@latest', 'prom-client@trunk'],
+		},
+	);
 }
 
 function setup(client, location) {
@@ -53,6 +91,8 @@ function setup(client, location) {
 		'gateway',
 		'method',
 		'status_code',
+		'phase',
+		'label1',
 	]);
 }
 

lib/metricAggregators.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const { Grouper, hashObject } = require('./util');
+const { LabelGrouper } = require('./util');
 
 /**
  * Returns a new function that applies the `aggregatorFn` to the values.
@@ -18,17 +18,20 @@ function AggregatorFactory(aggregatorFn) {
 			aggregator: metrics[0].aggregator,
 		};
 		// Gather metrics by metricName and labels.
-		const byLabels = new Grouper();
+		const byNames = new Map();
 		metrics.forEach(metric => {
 			metric.values.forEach(value => {
-				const key = value.metricName ?? '';
-				const group = byLabels.getOrAdd(key, () => new Grouper());
-
-				group.add(hashObject(value.labels), value);
+				const name = value.metricName ?? '';
+				let group = byNames.get(name);
+				if (group === undefined) {
+					group = new LabelGrouper();
+					byNames.set(name, group);
+				}
+				group.add(value);
 			});
 		});
 		// Apply aggregator function to gathered metrics.
-		byLabels.forEach(group => {
+		byNames.forEach(group => {
 			group.forEach(values => {
 				const valObj = {
 					value: aggregatorFn(values),

lib/util.js

@@ -357,26 +357,180 @@ class Grouper extends Map {
 			this.set(key, [value]);
 		}
 	}
+}
+
+exports.Grouper = Grouper;
+
+const GROWTH_RATE = 1.25;
+
+/**
+ * For grouping metrics by labels for reporting purposes.
+ */
+class LabelGrouper {
+	/** @type {string[]} */
+	#labelNames = new Array(6).fill('');
+
+	/** @type {Map<string, Array<any>>} */
+	#map = new Map();
 
 	/**
-	 * Returns a child record or creates one if it does not exist
-	 *
-	 * If there is no record at the location of the key, the init() function is
-	 * called to create an object to put there. This allows for nested structures.
-	 *
-	 * @param {*} key Key to verify
-	 * @param {[Function]} init function to generate an empty record
-	 * @returns {undefined} undefined
+	 * Current number of columns
+	 * @type {number}
 	 */
-	getOrAdd(key, init = () => []) {
-		let entry = this.get(key);
-		if (entry === undefined) {
-			entry = init();
-			this.set(key, entry);
+	#count = 0;
+
+	/**
+	 * Create a grouper.
+	 */
+	constructor() {}
+
+	/**
+	 * Adds the `value` to the `key`'s array of values.
+	 * @param {StatsEntry} value Value to add to `key`'s array.
+	 * @returns {LabelGrouper} undefined.
+	 */
+	add(value) {
+		const labels = value.labels;
+		const key = this.keyFrom(labels);
+
+		const entry = this.#map.get(key);
+		if (entry !== undefined) {
+			entry.push(value);
+		} else {
+			this.#map.set(key, [value]);
 		}
 
-		return entry;
+		return this;
+	}
+
+	/**
+	 * Look up an entry by labels.
+	 * Note: This can end up modifying the store if labels are missing.
+	 * @param {object} labels Key to retrieve.
+	 * @returns {Array<StatsEntry>} undefined.
+	 */
+	get(labels) {
+		return this.#map.get(this.keyFrom(labels));
+	}
+
+	/**
+	 * Return all of the entries in this collection.
+	 * @returns {Array<StatsEntry>}
+	 */
+	values() {
+		return Array.from(this.#map.values()).filter(entry => entry.length > 0);
+	}
+
+	/**
+	 * Loop over the entries.
+	 * @param fn {Function}
+	 */
+	forEach(fn) {
+		return this.#map.forEach(fn);
+	}
+
+	/**
+	 * Remove all values from the Grouper.
+	 * Leaves the entries, but zeroes out the value arrays.
+	 * @returns {LabelGrouper}
+	 */
+	clear() {
+		for (const entry of this.#map.values()) {
+			entry.length = 0;
+		}
+
+		return this;
+	}
+
+	/**
+	 * Create a key for the given labels.
+	 * Note: This can end up modifying the store if labels are missing.
+	 * @param labels
+	 * @returns {string}
+	 */
+	keyFrom(labels = {}) {
+		const keys = Object.keys(labels);
+
+		if (keys.length === 0) {
+			return '';
+		}
+
+		const arr = new Array(this.#labelNames.length);
+
+		let count = 0;
+		for (let i = 0; i < this.#count; i++) {
+			const name = this.#labelNames[i];
+			const value = labels[name];
+
+			if (value !== undefined) {
+				arr[i] = value;
+				count++;
+			}
+		}
+
+		if (count < keys.length) {
+			let pos = this.#count;
+			const missing = this.#expandLabels(labels);
+			for (const name of missing) {
+				arr[pos++] = labels[name];
+			}
+		}
+
+		return arr.join('|');
+	}
+
+	/**
+	 * Size of the collection.
+	 * @returns {number}
+	 */
+	get size() {
+		return this.#map.size;
+	}
+
+	/**
+	 * Search the labels for missing values and expand the lookup table to handle them.
+	 * @param labels
+	 * @returns {*[]}
+	 */
+	#expandLabels(labels) {
+		const missing = [];
+
+		for (const name of Object.keys(labels)) {
+			if (this.#labelNames.indexOf(name) === -1) {
+				missing.push(name);
+			}
+		}
+
+		const target = missing.length + this.#count;
+		const current = this.#labelNames.length;
+		let width = current;
+
+		if (target > width) {
+			while (target > width) {
+				width = Math.ceil(width * GROWTH_RATE);
+			}
+
+			this.#labelNames.length = width;
+			this.#labelNames.fill('', current, width);
+
+			const extension = '|'.repeat(width - current);
+			const newMap = new Map();
+
+			for (const [key, value] of this.#map.entries()) {
+				newMap.set(`${key}${extension}`, value);
+			}
+
+			this.#map = newMap;
+		}
+
+		for (let i = this.#count, j = 0; j < missing.length; i++, j++) {
+			this.#labelNames[i] = missing[j];
+		}
+
+		this.#count = target;
+
+		return missing;
 	}
 }
 
-exports.Grouper = Grouper;
+module.exports.LabelGrouper = LabelGrouper;