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QoS: only bandwidth limiter has effect

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Though, be aware your ISP (download) or your modem (upload) may not be suffering from bufferbloat. DOCSIS 3.1 (IIRC) even includes an AQM like CoDel in the standard itself, which I assume many cable internet customers will have soonish if not already.

Codel is popular because it's basically hands-off, and it works well enough...

I'm using Hierarchical Fair Service Curves, which while much older than Codel, once tuned, it works well.. I like having the knobs/levels at the routing layer, but getting the most out of it requires a pretty deep understanding of Schedulers, Queues, and Priorities - not for everyone ;)
 
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I've checked this now and set my download cap to 76mbit/s, which is 80% of my 95.x-mbit/s real-world maximum speed. I've checked the bufferbloat several times with both settings: The difference in latency is around 1-2ms, 3ms at most, meaning that I gain 1-3ms better latency when sacrificing 19mbit/s of my total bandwidth limit.

Set your cap to 95 percent of Max on the download side, and you'll be fine with most QoS platforms...
 
And remember with QoS, it's ok to overcommit resources, as not all queues are full all of the time - and priorities matter..

QoS is not about establishing limits, it's about committing resources - and higher priorities will win over lower ones, so if you work it right, you'll have great performance...
 
First of all sorry for the weeks long delay in my reply... haven't seen the notification until now and recently I don't log on here that often.



1. the ping from the phone times out in those cases, i.e. not all of the pings arrive when I try that
2. yes, the current bandwidth limit that I've set is the optimal one. I even get worse results if I "reserve" too much bandwidth by e.g. capping it at 80% of what my line is capable off - doing this is a common advice when setting up QoS but it's an advice I'd rather not follow, after all my testing. The best results are achieved though capping it *just* *below* what the line is capable of in real-life, which is measured through various speed-tests at different times. By "just below" I mean something like 1mbit/s below.

I have a N66u and use Merlin's 280.59. For me capping at 80% did wonders! Before I was hassling with the bandwidth limiter but the results were mixed.
Bufferbloat went from F to B (or C) but the speed dropped to like 80 Mb/s, sometimes even lower (My ISP connection is: 150/15).

I like to play online games like Battlefield and Fifa so smoothness before speed. I noticed my ping was still jumping too much resulting in lag.
I thought that wasn't worth the trade-off.

So I've decided to give QOS another try after reading this topic and others (I've tried QOS before but I was getting some shirtty results)
Did a speedtest and the results were: 154 Mb/s down and 10 Mb/s up. My actual up is 15 Mb/s but I've noticed the bufferbloat went crazy when it goes past 10 Mb/s (I've read somewhere that the upload is the cause for bufferbloat) With that on my mind I took 80% of 10 Mb/s up and 80% of 154 down resulting in 123 Mb/s down and 8 Mb/s up.

I've set the user-defined QOS rules and priorities accordingly and the results are wowwww!! Ping went from A and B on Dslreports to A+ steady plus my speed went up to 106 Mb/s

Gaming now is like a whole new experience for real. Smooth as butter, low ping and no spikes! I'm very happy now and I'm not touching it anymore ;)

Thank you all for you helpful tips, especially Merlin!! QOS does work..
 
zino86 - Can you clarify - which QoS mode did you set - adaptive, traditional, or Bandwidth Limiter? what parameters did you specify for it?
 
Any luck vrapp?

I have a DSL-AC68U and am also finding I'm getting no benefit from either Adaptive or Traditional QoS. Using Traditional QoS, I've set the max download rate to 50% for all priority levels except Highest. I've set the total download bandwidth to 90% of what I get on speedtest. The first row of my QoS rules is my game port at Highest priority, the next row is a catch all at Low priority. I start a large download (update for another game) that maxes out my connection, then try to play the game. From my understanding when I start playing the game it should reduce the max bandwidth for all other packets from 100% to 50% total download bandwidth, and the download rate as seen from my computer should drop immediately. The actual amount of data being sent by the server will take a few seconds to come down but once it does, my game should have almost 20% of the download bandwidth reserved. The speed of my game update download is not changing at all though, continuing to use 100% of the bandwidth.
 

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