src/performance/PerformanceStatistics.ts

   1 // Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
   2
   3 import { type PerformanceEntry, PerformanceObserver, performance } from 'node:perf_hooks';
   4 import type { URL } from 'node:url';
   5 import { parentPort } from 'node:worker_threads';
   6
   7 import { MessageChannelUtils } from '../charging-station';
   8 import {
   9   type IncomingRequestCommand,
  10   MessageType,
  11   type RequestCommand,
  12   type Statistics,
  13   type TimeSeries,
  14 } from '../types';
  15 import { CircularArray, Configuration, Constants, Utils, logger } from '../utils';
  16
  17 export class PerformanceStatistics {
  18   private static readonly instances: Map<string, PerformanceStatistics> = new Map<
  19     string,
  20     PerformanceStatistics
  21   >();
  22
  23   private readonly objId: string;
  24   private readonly objName: string;
  25   private performanceObserver!: PerformanceObserver;
  26   private readonly statistics: Statistics;
  27   private displayInterval!: NodeJS.Timeout;
  28
  29   private constructor(objId: string, objName: string, uri: URL) {
  30     this.objId = objId;
  31     this.objName = objName;
  32     this.initializePerformanceObserver();
  33     this.statistics = {
  34       id: this.objId ?? 'Object id not specified',
  35       name: this.objName ?? 'Object name not specified',
  36       uri: uri.toString(),
  37       createdAt: new Date(),
  38       statisticsData: new Map(),
  39     };
  40   }
  41
  42   public static getInstance(
  43     objId: string,
  44     objName: string,
  45     uri: URL
  46   ): PerformanceStatistics | undefined {
  47     if (!PerformanceStatistics.instances.has(objId)) {
  48       PerformanceStatistics.instances.set(objId, new PerformanceStatistics(objId, objName, uri));
  49     }
  50     return PerformanceStatistics.instances.get(objId);
  51   }
  52
  53   public static beginMeasure(id: string): string {
  54     const markId = `${id.charAt(0).toUpperCase()}${id.slice(1)}~${Utils.generateUUID()}`;
  55     performance.mark(markId);
  56     return markId;
  57   }
  58
  59   public static endMeasure(name: string, markId: string): void {
  60     performance.measure(name, markId);
  61     performance.clearMarks(markId);
  62     performance.clearMeasures(name);
  63   }
  64
  65   public addRequestStatistic(
  66     command: RequestCommand | IncomingRequestCommand,
  67     messageType: MessageType
  68   ): void {
  69     switch (messageType) {
  70       case MessageType.CALL_MESSAGE:
  71         if (
  72           this.statistics.statisticsData.has(command) &&
  73           this.statistics.statisticsData.get(command)?.countRequest
  74         ) {
  75           this.statistics.statisticsData.get(command).countRequest++;
  76         } else {
  77           this.statistics.statisticsData.set(command, {
  78             ...this.statistics.statisticsData.get(command),
  79             countRequest: 1,
  80           });
  81         }
  82         break;
  83       case MessageType.CALL_RESULT_MESSAGE:
  84         if (
  85           this.statistics.statisticsData.has(command) &&
  86           this.statistics.statisticsData.get(command)?.countResponse
  87         ) {
  88           this.statistics.statisticsData.get(command).countResponse++;
  89         } else {
  90           this.statistics.statisticsData.set(command, {
  91             ...this.statistics.statisticsData.get(command),
  92             countResponse: 1,
  93           });
  94         }
  95         break;
  96       case MessageType.CALL_ERROR_MESSAGE:
  97         if (
  98           this.statistics.statisticsData.has(command) &&
  99           this.statistics.statisticsData.get(command)?.countError
 100         ) {
 101           this.statistics.statisticsData.get(command).countError++;
 102         } else {
 103           this.statistics.statisticsData.set(command, {
 104             ...this.statistics.statisticsData.get(command),
 105             countError: 1,
 106           });
 107         }
 108         break;
 109       default:
 110         // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
 111         logger.error(`${this.logPrefix()} wrong message type ${messageType}`);
 112         break;
 113     }
 114   }
 115
 116   public start(): void {
 117     this.startLogStatisticsInterval();
 118     if (Configuration.getPerformanceStorage().enabled) {
 119       logger.info(
 120         `${this.logPrefix()} storage enabled: type ${
 121           Configuration.getPerformanceStorage().type
 122         }, uri: ${Configuration.getPerformanceStorage().uri}`
 123       );
 124     }
 125   }
 126
 127   public stop(): void {
 128     if (this.displayInterval) {
 129       clearInterval(this.displayInterval);
 130       delete this.displayInterval;
 131     }
 132     performance.clearMarks();
 133     performance.clearMeasures();
 134     this.performanceObserver?.disconnect();
 135   }
 136
 137   public restart(): void {
 138     this.stop();
 139     this.start();
 140   }
 141
 142   private initializePerformanceObserver(): void {
 143     this.performanceObserver = new PerformanceObserver((performanceObserverList) => {
 144       const lastPerformanceEntry = performanceObserverList.getEntries()[0];
 145       // logger.debug(
 146       //   `${this.logPrefix()} '${lastPerformanceEntry.name}' performance entry: %j`,
 147       //   lastPerformanceEntry
 148       // );
 149       this.addPerformanceEntryToStatistics(lastPerformanceEntry);
 150     });
 151     this.performanceObserver.observe({ entryTypes: ['measure'] });
 152   }
 153
 154   private logStatistics(): void {
 155     logger.info(`${this.logPrefix()}`, {
 156       ...this.statistics,
 157       statisticsData: Utils.JSONStringifyWithMapSupport(this.statistics.statisticsData),
 158     });
 159   }
 160
 161   private startLogStatisticsInterval(): void {
 162     if (Configuration.getLogStatisticsInterval() > 0 && !this.displayInterval) {
 163       this.displayInterval = setInterval(() => {
 164         this.logStatistics();
 165       }, Configuration.getLogStatisticsInterval() * 1000);
 166       logger.info(
 167         `${this.logPrefix()} logged every ${Utils.formatDurationSeconds(
 168           Configuration.getLogStatisticsInterval()
 169         )}`
 170       );
 171     } else if (this.displayInterval) {
 172       logger.info(
 173         `${this.logPrefix()} already logged every ${Utils.formatDurationSeconds(
 174           Configuration.getLogStatisticsInterval()
 175         )}`
 176       );
 177     } else {
 178       logger.info(
 179         `${this.logPrefix()} log interval is set to ${Configuration.getLogStatisticsInterval()?.toString()}. Not logging statistics`
 180       );
 181     }
 182   }
 183
 184   private median(dataSet: number[]): number {
 185     if (Array.isArray(dataSet) === true && dataSet.length === 1) {
 186       return dataSet[0];
 187     }
 188     const sortedDataSet = dataSet.slice().sort((a, b) => a - b);
 189     const middleIndex = Math.floor(sortedDataSet.length / 2);
 190     if (sortedDataSet.length % 2) {
 191       return sortedDataSet[middleIndex / 2];
 192     }
 193     return (sortedDataSet[middleIndex - 1] + sortedDataSet[middleIndex]) / 2;
 194   }
 195
 196   // TODO: use order statistics tree https://en.wikipedia.org/wiki/Order_statistic_tree
 197   private percentile(dataSet: number[], percentile: number): number {
 198     if (percentile < 0 && percentile > 100) {
 199       throw new RangeError('Percentile is not between 0 and 100');
 200     }
 201     if (Utils.isEmptyArray(dataSet)) {
 202       return 0;
 203     }
 204     const sortedDataSet = dataSet.slice().sort((a, b) => a - b);
 205     if (percentile === 0) {
 206       return sortedDataSet[0];
 207     }
 208     if (percentile === 100) {
 209       return sortedDataSet[sortedDataSet.length - 1];
 210     }
 211     const percentileIndex = (percentile / 100) * sortedDataSet.length - 1;
 212     if (Number.isInteger(percentileIndex)) {
 213       return (sortedDataSet[percentileIndex] + sortedDataSet[percentileIndex + 1]) / 2;
 214     }
 215     return sortedDataSet[Math.round(percentileIndex)];
 216   }
 217
 218   private stdDeviation(dataSet: number[]): number {
 219     let totalDataSet = 0;
 220     for (const data of dataSet) {
 221       totalDataSet += data;
 222     }
 223     const dataSetMean = totalDataSet / dataSet.length;
 224     let totalGeometricDeviation = 0;
 225     for (const data of dataSet) {
 226       const deviation = data - dataSetMean;
 227       totalGeometricDeviation += deviation * deviation;
 228     }
 229     return Math.sqrt(totalGeometricDeviation / dataSet.length);
 230   }
 231
 232   private addPerformanceEntryToStatistics(entry: PerformanceEntry): void {
 233     const entryName = entry.name;
 234     // Initialize command statistics
 235     if (!this.statistics.statisticsData.has(entryName)) {
 236       this.statistics.statisticsData.set(entryName, {});
 237     }
 238     // Update current statistics
 239     this.statistics.updatedAt = new Date();
 240     this.statistics.statisticsData.get(entryName).countTimeMeasurement =
 241       this.statistics.statisticsData.get(entryName)?.countTimeMeasurement
 242         ? this.statistics.statisticsData.get(entryName).countTimeMeasurement + 1
 243         : 1;
 244     this.statistics.statisticsData.get(entryName).currentTimeMeasurement = entry.duration;
 245     this.statistics.statisticsData.get(entryName).minTimeMeasurement =
 246       this.statistics.statisticsData.get(entryName)?.minTimeMeasurement
 247         ? this.statistics.statisticsData.get(entryName).minTimeMeasurement > entry.duration
 248           ? entry.duration
 249           : this.statistics.statisticsData.get(entryName).minTimeMeasurement
 250         : entry.duration;
 251     this.statistics.statisticsData.get(entryName).maxTimeMeasurement =
 252       this.statistics.statisticsData.get(entryName)?.maxTimeMeasurement
 253         ? this.statistics.statisticsData.get(entryName).maxTimeMeasurement < entry.duration
 254           ? entry.duration
 255           : this.statistics.statisticsData.get(entryName).maxTimeMeasurement
 256         : entry.duration;
 257     this.statistics.statisticsData.get(entryName).totalTimeMeasurement =
 258       this.statistics.statisticsData.get(entryName)?.totalTimeMeasurement
 259         ? this.statistics.statisticsData.get(entryName).totalTimeMeasurement + entry.duration
 260         : entry.duration;
 261     this.statistics.statisticsData.get(entryName).avgTimeMeasurement =
 262       this.statistics.statisticsData.get(entryName).totalTimeMeasurement /
 263       this.statistics.statisticsData.get(entryName).countTimeMeasurement;
 264     this.statistics.statisticsData.get(entryName)?.timeMeasurementSeries instanceof CircularArray
 265       ? this.statistics.statisticsData
 266           .get(entryName)
 267           ?.timeMeasurementSeries?.push({ timestamp: entry.startTime, value: entry.duration })
 268       : (this.statistics.statisticsData.get(entryName).timeMeasurementSeries =
 269           new CircularArray<TimeSeries>(Constants.DEFAULT_CIRCULAR_BUFFER_CAPACITY, {
 270             timestamp: entry.startTime,
 271             value: entry.duration,
 272           }));
 273     this.statistics.statisticsData.get(entryName).medTimeMeasurement = this.median(
 274       this.extractTimeSeriesValues(
 275         this.statistics.statisticsData.get(entryName).timeMeasurementSeries
 276       )
 277     );
 278     this.statistics.statisticsData.get(entryName).ninetyFiveThPercentileTimeMeasurement =
 279       this.percentile(
 280         this.extractTimeSeriesValues(
 281           this.statistics.statisticsData.get(entryName).timeMeasurementSeries
 282         ),
 283         95
 284       );
 285     this.statistics.statisticsData.get(entryName).stdDevTimeMeasurement = this.stdDeviation(
 286       this.extractTimeSeriesValues(
 287         this.statistics.statisticsData.get(entryName).timeMeasurementSeries
 288       )
 289     );
 290     if (Configuration.getPerformanceStorage().enabled) {
 291       parentPort?.postMessage(
 292         MessageChannelUtils.buildPerformanceStatisticsMessage(this.statistics)
 293       );
 294     }
 295   }
 296
 297   private extractTimeSeriesValues(timeSeries: CircularArray<TimeSeries>): number[] {
 298     return timeSeries.map((timeSeriesItem) => timeSeriesItem.value);
 299   }
 300
 301   private logPrefix = (): string => {
 302     return Utils.logPrefix(` ${this.objName} | Performance statistics`);
 303   };
 304 }