src/performance/PerformanceStatistics.ts

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