Online gaming and file downloads - latency hell!

[Morgan Wesström]

On 2010-06-16 02:51, Modulok wrote:
> Yo,
> 
> I have a FreeBSD box acting as a router between me and the Internet.
> Whenever someone on the local network downloads something, the other
> connections have a really high latency. A second or more. For people
> who like to download large files and play online games, it's not good.
> 
> I tried traffic shaping with PF, which works - almost: I tried the
> home example in the PF book, but it doesn't work out so well. I can
> throttle users with no trouble, but even so that doesn't seem to help
> the latency issue unless I choke the 'big file download' users almost
> completely off. It's like nothing helps. I tried a priority based
> queue where all traffic on the gaming ports was placed in front of all
> other traffic, and while I saw a very mild improvement, latency was
> still really pitiful.
> 
> Is there anything else I can do? Anyone have a similar setup and wish
> to share config files? Are there some sysctl's that would help this
> out or something. I'm almost ready to just buy a 'gaming' *gag* router
> which implements their own brand of QoS, but don't want to sink to
> that level if I don't have to.
> 
> Help!
> -Modulok-

Traffic shaping on your side when downloading unfortunately doesn't help
you. The data has already been transferred across your cable or DSL
connection by then and reordering any packets on your side will not
change the latency. Traffic shaping your download has to be performed at
your upstream router which you probably don't control. PF can help you
traffic shape your outgoing traffic. I have used it for this for the
past 6 years to help me maintain a low and stable ping while I play
online, even if I upload simultaneously. I've read about people trying
to throttle outgoing ACKs to slow down their download but that still
wouldn't rearrange any incoming data packets so I don't see how that
would help. I haven't tried it myself though but neither have I read
about anyone successfully accomplishing this.

Regards
Morgan