How Bittorrent Uploads Effect Response Times
As you most likely know, if you use bit torrent at it’s maximum speed, your internet connection seems to slow to a crawl for everything else. Web pages may fail to load, ping times shoot into the stratosphere, and tempers may rise from others trying to use the connection. But what level of traffic causes these issues? Is it simply because most of the internet connection is used, or do torrents increase ping times no matter what?. I decided to find out, and here are my results.
Method: A cable internet connection was used with tested thourput of 625KBs (5,000kbs) download and 250KBs (2,000kbs) upload. Azureus is my torrent program of choice, so I decided to use it for this test. I allowed Azurues to increase upload until it reached the set threshold is reached, then take an average of 25 pings to www.google.com. Results were collected from 2:00am to 2:30am on July 10, 2008. In order to minimize any type of possible interference from neighbors. Download speeds were set to a consitant 150KBs.
****Results****
Speed Min/Avg/Max/Max-def
Baseline: 8.815/10.041/12.910/0.955 ms
50KBs: 9.007/11.460/16.150/1.912 ms
100KBs: 8.337/11.994/18.904/3.071 ms
150KBs: 9.196/14.508/26.676/5.117 ms
200KBs: 9.092/19.435/40.647/10.277 ms
210KBs: 8.706/19.009/43.258/9.554 ms
220KBs: 8.791/20.588/42.393/10.422 ms
230KBs: 8.967/25.411/75.253/17.969 ms
240KBs: 8.876/25.765/46.312/11.110 ms
250KBs: 10.168/35.137/86.564/22.508 ms
MAX(about 270KBs): 191.541/364.431/530.431/80.616 ms
Conclusion: Ping times remain acceptable untill a mere 10KBs below maximum speed. After maximum speed is reached ping times increase dramatically, to the point where the internet connection is no longer usable. In this scenario I would personally leave my upload speed at 220KBs, but that is personal preference. Because I host a website on this internet connection, I usually leave my torrent upload at 200KBs and my download at 150KBs, this makes sure that I have plenty of bandwidth for hosting this site. In addition, I use the auto speed select feature in Azureus to automatically reduce speeds as needed if more bandwidth is needed by my web server.