Understanding QOS-not doing what I expected.

[davexnet]

Hello all -
I'm trying to understand what I'm seeing, and whether I can improve the situation.
The problem involves a lightly-used Utorrent. (less than 100 connections)
Here's the details of the problem:

My ISP provides me with 64KB upload. I set Utorrent to upload at 55KB
and download at 300KB. It does this just fine (with QOS off).
However, when I turn on QOS in the router, the upload slows to 45KB
and the 300 down is maintained.

Why? I set the category in Tomato (wrt54gl) to have upload bandwidth of 60KB.
Why the slow down?
I've looked at the router real time stats - I think the answer is there,
but I don't know how to interpret it.


Thanks for any suggestions.

 

[ScottMac]

Post your (sanitized) config and stats.

 

[Pantlegz]

what are you using QoS for anyway? isn't it typically only used for voip and commercial applications or throttling bandwidth to/from certain applications(ports)? this could be the result of overhead, the router has to do more stuff for the packet to get out I would think it only effects latency but it could have something to do with this as well. Have you tried changing the upload bandwidth to 70KB?

 

[spidey07]

It's probably the router getting overloaded when qos is turned on. Or possibly the different buffers/queues are getting full and it's dropping some which would slow your throughput.

Having anything run that close to the maximum of your connection would likely result in packet loss anyway.

 

[davexnet]

Thanks for the responses. The only reason I activated QOS was to ensure that normal web browsing
would continue to operate at low latency when Utorrent was active. One of the things I saw in the
Tomato real time graph was 85% of upload BW going to "bulk" (that would be Utorrent),
while 15% of BW was going to "highest" which would be DNS. Does that seem odd ?

My ISP has just increased my upload BW, so now I've got more headroom and can at least rule out
getting too close to the limit. But leaving the QOS settings and the upload limit in the Utorrrent the same
(for the purpose of analyzing the problem), the issue still remains. I'll see if I can post some
pictures - I think I've explained it all, but a pictures worth a 1000 words (as they say)
Thanks!
Dave

 

[davexnet]

This is what I see in the real time monitoring.
It equates to an upload of approx 46KB in Utorrent (which is set to
55, but unable attain it with QOS on)


http://img19.imageshack.us/img19/9384/qos1rsr.jpg

 

[QueBert]

not to jack this thread, but I'm having an Ooma delivered today so I can get VOIP going. I currently have a Motorola SB900 which is a modem + wireless router in one. It's not the best (ok it sucks lol) but it's been getting the job done thus far. How important is QOS to VOIP? Reading around it seems a lot of people use it, but some don't. And they don't seem to be complaining about any problems, but if I need to buy a router with QOS I will.

 

[Pantlegz]

Originally posted by: QueBert
not to jack this thread, but I'm having an Ooma delivered today so I can get VOIP going. I currently have a Motorola SB900 which is a modem + wireless router in one. It's not the best (ok it sucks lol) but it's been getting the job done thus far. How important is QOS to VOIP? Reading around it seems a lot of people use it, but some don't. And they don't seem to be complaining about any problems, but if I need to buy a router with QOS I will.

Not to be a dick, but make your own thread. And for VOIP I would suggest using QoS.

To the OP I would agree with what spidey said. Other than that try to bump the upload up, to say 65KB and see what happens. If it caps at ~46KB then thats apparently all the router can filter with QoS effectively.

If you're doing this just to keep normal web browsing quick, just limit the number of connections in utorrent as well as the UL/DL limits in the program. As long as not all you bandwidth is being eaten up and there are 10000's of connections your router is attempting to create all should be ok

 

[davexnet]

Well I upgraded to a new release of the Tomato firmware and it's behaving better.
In the QOS graphs, the "lowest" category seems to be using 98% of
allocated bandwidth rather than the 85% under the previous FW release.
I also turned off "ack" priority which also helps with p2p/ Bit torrent.

A Second benefit of the newer FW is that the radio link between the
router and my wireless PC has improved, much less send/receive retries.

Thirdly, my ISP has doubled my upload bandwidth, and I can now maintain
300KB down, 95KB up (p2p) with QOS on, with pretty good web browsing response
simultaneously.

Thanks for your suggestions.