Function calculateFrameTimeStats

src/ChartGPU.ts:995–1042

()

  };

  const calculateFrameTimeStats = (): FrameTimeStats => {
    if (frameTimestampCount < 2) {
      return {
        min: 0 as Milliseconds,
        max: 0 as Milliseconds,
        avg: 0 as Milliseconds,
        p50: 0 as Milliseconds,
        p95: 0 as Milliseconds,
        p99: 0 as Milliseconds,
      };
    }

    const startIndex = (frameTimestampIndex - frameTimestampCount + FRAME_BUFFER_SIZE) % FRAME_BUFFER_SIZE;
    
    const deltas = new Array<number>(frameTimestampCount - 1);
    let min = Number.POSITIVE_INFINITY;
    let max = Number.NEGATIVE_INFINITY;
    let sum = 0;
    
    for (let i = 1; i < frameTimestampCount; i++) {
      const prevIndex = (startIndex + i - 1) % FRAME_BUFFER_SIZE;
      const currIndex = (startIndex + i) % FRAME_BUFFER_SIZE;
      const delta = frameTimestamps[currIndex] - frameTimestamps[prevIndex];
      deltas[i - 1] = delta;
      
      if (delta < min) min = delta;
      if (delta > max) max = delta;
      sum += delta;
    }

    const avg = sum / deltas.length;

    // Sort for percentile calculations
    deltas.sort((a, b) => a - b);

    const p50Index = Math.floor(deltas.length * 0.50);
    const p95Index = Math.floor(deltas.length * 0.95);
    const p99Index = Math.floor(deltas.length * 0.99);

    return {
      min: min as Milliseconds,
      max: max as Milliseconds,
      avg: avg as Milliseconds,
      p50: deltas[p50Index] as Milliseconds,
      p95: deltas[p95Index] as Milliseconds,
      p99: deltas[p99Index] as Milliseconds,
    };
  };

  const calculatePerformanceMetrics = (): PerformanceMetrics => {
    const fps = calculateExactFPS();