QoS on RT-AC68U and 200Mbps connection

Hi,

I've upgraded my connection to 200Mbps today and as expected the RT-AC68U struggles with that bandwidth when QoS is activated. It tops out at 165 Mbps, which is not that bad, but still I'm not using 100% of the available bandwidth. When QoS is off, no problem I hit the 200Mbps.

So, when hitting that kind of bandwidth, is QoS really important? When I had a 100Mbps connection if I didn't activate QoS I would have the occasional trouble when I had a full speed download, Skype and a streaming service (Spotify, Youtube, Twitch, etc).

So what's your opinion on that? If a router upgrade is recommended, which one would support QoS with that type of connection?

Simple enough to try your new connection without QoS for a week or so. And the direct answer is that the RT-AC68U should easily support that ISP level without needing hardware acceleration enabled.

What firmware are you running? Consider upgrading to the latest (check manually) from Asus or preferably, I suggest the RMerlin fork instead. A reset to factory defaults with a manual and minimal configuration of the router to secure it and connect to the ISP is also recommended. And consider using new ssid's too (or; forget and re-associate the old ssid on all clients - but just easier to use a new one).

Is that 165Mbps topping out with a single client? How are you testing? Can multiple clients approach the 200Mbps your ISP provides? It may simply be a matter of the web service you are connecting to not able to give more too.

Disable QoS, reboot, make sure hardware acceleration is enabled, reboot again (and check a final time) and use it for a few days as-is. I think you may find QoS is no longer required.

L&LD said:

Simple enough to try your new connection without QoS for a week or so. And the direct answer is that the RT-AC68U should easily support that ISP level without needing hardware acceleration enabled.

Click to expand...

It does support the 200Mbps, but as I said, without QoS...

L&LD said:

What firmware are you running? Consider upgrading to the latest (check manually) from Asus or preferably, I suggest the RMerlin fork instead. A reset to factory defaults with a manual and minimal configuration of the router to secure it and connect to the ISP is also recommended. And consider using new ssid's too (or; forget and re-associate the old ssid on all clients - but just easier to use a new one).

Click to expand...

I'm running Merlin Fork 374.43_2-10j9527 (latest).
Why new SSID's? Is this FW update related or ISP connection?

L&LD said:

Is that 165Mbps topping out with a single client? How are you testing? Can multiple clients approach the 200Mbps your ISP provides? It may simply be a matter of the web service you are connecting to not able to give more too.

Click to expand...

Single client, testing with a download on a FTP server that tops out the connection (203 Mbps) when QoS is disabled and that can't go above 165 Mbps when QoS is enbaled.

L&LD said:

Disable QoS, reboot, make sure hardware acceleration is enabled, reboot again (and check a final time) and use it for a few days as-is. I think you may find QoS is no longer required.

Click to expand...

I have no problems when QoS is disabled, only when it is enbaled... And yes, HW acceleration is enabled.
I'll test for a couple of days and see if I see a difference and if QoS really is necessary for my everyday use.

Thanks again for your answer!

As a partially related bump, how stable has Merlin been on your 68U? The last experience I had with AsusWRT was about 3 months ago with the latest Merlin (at that time) on an RT-N16, and I ended up returning it due to flakiness with any firmware I tried (stock, Merlin, DD-WRT, AdvancedTomato). I attribute that more to probable shortcomings of the model itself, so just curious...

Merlin Fork has been extremely stable for me... I've been using it for the past 4 months and apart from a small custom DDNS bug in release 9, I have nothing to report.

I thought QoS and hardware acceleration did not work together.


Have you tried the standard QoS?

What is the CPU usage when downloading while QoS is enabled?

What do you mean by standard QoS? I am using the QoS available through "Traffic Manager" in the UI (as a reminder i am running Merlin Fork 374.43 update 10).

Here is the CPU usage (from the "top" command - all CPU usage related to DL/UL is taken by sirq):
-With QoS disabled:
*DL: ~25%
*UL ~10%

-With QoS enabled:
*DL: ~56%
*UL: ~13%

Thanks again for your help!

I thought the new Asus routers had Adaptive QoS and standard QoS.

Your CPU usage seems fine. Have you Factory Defaulted/Reset your settings?

Nullity said:

I thought the new Asus routers had Adaptive QoS and standard QoS.

Click to expand...

Interesting... I'm going to look into that.

Nullity said:

Your CPU usage seems fine. Have you Factory Defaulted/Reset your settings?

Click to expand...

Yes, I did yesterday and tried to set the router up with a minimal QoS configuration and still had the same issue...