src/performance/PerformanceStatistics.ts

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