unique videos in total,
and the video durations range from 2 to 7518 seconds.
Among them, 76.3% is less than 5 minutes,
91.82% is less than 10 minutes,
and 97.66% is less than 25 minutes.
The mean video duration is 283.46 seconds,
and the median duration is 159 seconds.
File Popularity: File popularity is defined as the distribution of stream requests on video files during a measurement interval. We performed goodness-of-fit test with several distribution models, and found Zipf with an exponential cutoff fits best and well on the file popularity at four time scales - 30 minutes, 1 hour,1 day, and 1 week.