if err == nil {
					response := time.Since(t)
					ttfb := time.Since(*fbr.t)
					// Only capture success criteria - do not
					// have to capture failed reads, truncated
					// reads etc.
					atomic.AddUint64(&totalBytesRead, uint64(n))
					mu.Lock()
					downloadTimes = append(downloadTimes, response)
					downloadTTFB = append(downloadTTFB, ttfb)
					mu.Unlock()
				}
				if err != nil {