src/performance/PerformanceStatistics.ts

   1 // Partial Copyright Jerome Benoit. 2021-2023. 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, TimeSeries } from '../types/Statistics';
  11 import { CircularArray, DEFAULT_CIRCULAR_ARRAY_SIZE } from '../utils/CircularArray';
  12 import Configuration from '../utils/Configuration';
  13 import logger from '../utils/Logger';
  14 import Utils from '../utils/Utils';
  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(),
  38     };
  39   }
  40
  41   public static getInstance(
  42     objId: string,
  43     objName: string,
  44     uri: URL
  45   ): PerformanceStatistics | undefined {
  46     if (!PerformanceStatistics.instances.has(objId)) {
  47       PerformanceStatistics.instances.set(objId, new PerformanceStatistics(objId, objName, uri));
  48     }
  49     return PerformanceStatistics.instances.get(objId);
  50   }
  51
  52   public static beginMeasure(id: string): string {
  53     const markId = `${id.charAt(0).toUpperCase()}${id.slice(1)}~${Utils.generateUUID()}`;
  54     performance.mark(markId);
  55     return markId;
  56   }
  57
  58   public static endMeasure(name: string, markId: string): void {
  59     performance.measure(name, markId);
  60     performance.clearMarks(markId);
  61     performance.clearMeasures(name);
  62   }
  63
  64   public addRequestStatistic(
  65     command: RequestCommand | IncomingRequestCommand,
  66     messageType: MessageType
  67   ): void {
  68     switch (messageType) {
  69       case MessageType.CALL_MESSAGE:
  70         if (
  71           this.statistics.statisticsData.has(command) &&
  72           this.statistics.statisticsData.get(command)?.countRequest
  73         ) {
  74           this.statistics.statisticsData.get(command).countRequest++;
  75         } else {
  76           this.statistics.statisticsData.set(
  77             command,
  78             Object.assign({ countRequest: 1 }, this.statistics.statisticsData.get(command))
  79           );
  80         }
  81         break;
  82       case MessageType.CALL_RESULT_MESSAGE:
  83         if (
  84           this.statistics.statisticsData.has(command) &&
  85           this.statistics.statisticsData.get(command)?.countResponse
  86         ) {
  87           this.statistics.statisticsData.get(command).countResponse++;
  88         } else {
  89           this.statistics.statisticsData.set(
  90             command,
  91             Object.assign({ countResponse: 1 }, this.statistics.statisticsData.get(command))
  92           );
  93         }
  94         break;
  95       case MessageType.CALL_ERROR_MESSAGE:
  96         if (
  97           this.statistics.statisticsData.has(command) &&
  98           this.statistics.statisticsData.get(command)?.countError
  99         ) {
 100           this.statistics.statisticsData.get(command).countError++;
 101         } else {
 102           this.statistics.statisticsData.set(
 103             command,
 104             Object.assign({ countError: 1 }, this.statistics.statisticsData.get(command))
 105           );
 106         }
 107         break;
 108       default:
 109         // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
 110         logger.error(`${this.logPrefix()} wrong message type ${messageType}`);
 111         break;
 112     }
 113   }
 114
 115   public start(): void {
 116     this.startLogStatisticsInterval();
 117     if (Configuration.getPerformanceStorage().enabled) {
 118       logger.info(
 119         `${this.logPrefix()} storage enabled: type ${
 120           Configuration.getPerformanceStorage().type
 121         }, uri: ${Configuration.getPerformanceStorage().uri}`
 122       );
 123     }
 124   }
 125
 126   public stop(): void {
 127     if (this.displayInterval) {
 128       clearInterval(this.displayInterval);
 129     }
 130     performance.clearMarks();
 131     performance.clearMeasures();
 132     this.performanceObserver?.disconnect();
 133   }
 134
 135   public restart(): void {
 136     this.stop();
 137     this.start();
 138   }
 139
 140   private initializePerformanceObserver(): void {
 141     this.performanceObserver = new PerformanceObserver((performanceObserverList) => {
 142       const lastPerformanceEntry = performanceObserverList.getEntries()[0];
 143       // logger.debug(
 144       //   `${this.logPrefix()} '${lastPerformanceEntry.name}' performance entry: %j`,
 145       //   lastPerformanceEntry
 146       // );
 147       this.addPerformanceEntryToStatistics(lastPerformanceEntry);
 148     });
 149     this.performanceObserver.observe({ entryTypes: ['measure'] });
 150   }
 151
 152   private logStatistics(): void {
 153     logger.info(`${this.logPrefix()}`, {
 154       ...this.statistics,
 155       statisticsData: Utils.JSONStringifyWithMapSupport(this.statistics.statisticsData),
 156     });
 157   }
 158
 159   private startLogStatisticsInterval(): void {
 160     if (Configuration.getLogStatisticsInterval() > 0) {
 161       this.displayInterval = setInterval(() => {
 162         this.logStatistics();
 163       }, Configuration.getLogStatisticsInterval() * 1000);
 164       logger.info(
 165         `${this.logPrefix()} logged every ${Utils.formatDurationSeconds(
 166           Configuration.getLogStatisticsInterval()
 167         )}`
 168       );
 169     } else {
 170       logger.info(
 171         `${this.logPrefix()} log interval is set to ${Configuration.getLogStatisticsInterval()?.toString()}. Not logging statistics`
 172       );
 173     }
 174   }
 175
 176   private median(dataSet: number[]): number {
 177     if (Array.isArray(dataSet) === true && 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) === true
 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 }