Traffic shaping and response. time, what can I expect?



  • Hey all,

    I just recently used the pfsense liveCD on one of my PCs to test it out, and used it betwwen my network and my DSL router.
    For reference, I have a 25/1 Mbit connection.

    The goal was to be able to use atleast most of hte connection for heavy bittorrent use, while still getting near optimal responsetime for all other programs, as if I wasn't running bittorrent at the same time.

    I tried setting it up to deprioritize bittorrent, prioritize HTTP and ICMP (thats what ping uses right?), then using bittorrent a lot, while testing rsponsetime via pinging my ISP server and measuring bandwidth for HTTP via www.tptest.se

    Without traffic shaping I only got a few mbits on tptest. with it I got about 12mbit - a good improvement.
    However, the reactiontime of websites seemed to be pretty heavily impacted regardless, and pingtimes were nowhere near the 12ms that is what I get whlile the connection is idle. I got anywhere between 50ms to 1000+ms and even a few dropped packets for ping.

    As far as I could tell the CPU never went above 20% use throughout.

    So the question is: Is this as good as I can expect it to get or am I dont something wrong?
    Also, is trafficshaping the same as QoS, or something else?

    I hope someone can explain this to me, as I am still very new to QoS features. Is there any way to actually tame bittorrent given enough processing power?…

    -Stigma



  • Read this thread when you've had a coffee and can spare a half hour:
    http://forum.pfsense.org/index.php/topic,2484.0.html

    It'll help you calculate appropriate values for your queues, I suspect with heavy P2P use and a huge asymetry in your link speeds, your ACK queue may be getting drops.
    The other possibility is that your PC is maxing it's connections and the slowdown/loss is local on your machine…



  • I don't know much (newb), but I was having bad results with games.  The solution for me was to lower the bandwidth settings in pf.  What I think was happening was that the connection was actually being overloaded.  I now set my max ul/dl setting to lower than actual and games are now smooth while I am d/l torrents.  This is probably the same for your situation.  Cable connections max speeds seem vary depending on what your neighbors are doing.



  • with QoS you will ALWAYS need to drop your overall bandwidth to 20 % less than the actual WAN connection up/down speeds from your ISP.

    Otherwise the ACK packets on your upload get jammed in a queue at the ISP equipment killing your attempts to do QoS.

    Yes it sounds like a waste of bandwidth but its a small price to pay for better traffic management.


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