SuperHub3 and Asus RT-AC68U - slow speed from this setup

[RedSimon]

Hi folks

I've found a couple of posts on a similar topic but neither addressed my issue.
- Hub3 / M500 - Router mode + AP instead of modem mode + router works well, but need better AP
-Superhub 3 and Asus RT-AC86U - Slow in Modem Mode

Let me set the scene.

Hub 3 in modem mode and connected to Asus RT-AC68U.  My setup has roughly 25-30 devices connected, 50/50 wired off Netgear gb switch and the rest mainly 5ghz wifi.  I had a 200mb virgin package and was happy with it, more often than not hitting that on all wired devices, and decent wifi too.

Kids started moaning about lag and dropouts with their PC gaming (all wired), so in January I moved to Virgin's 500mb package for just a few quid more.

Since then, speed has improved, but from my Asus router (Merlin fw 386.1_2) it's telling me 'Internet Speed' is maxing out at about 275mb.  Upload speed is rock-solid 36mb all the time.

PS - The Ookla SpeedTest feature in the Merlin firmware is fab, and worth the upgrade in itself (why they VM add this to the Superhub?), plus knowing my cables to the Asus are running at 1gb.

Virgin Helpdesk were adamant that the line was working as it should (that's always their reply though, right?) and I should put SH3 in router mode to fix it.  They were right 😞   

1. I put SH3 in router mode, with only Laptop wired to it.  This gave me full speed when tested from laptop - max 530mb down and 36mb up.  Even my iPhone upstairs got 295mb on speedtest.
2. Cabling Laptop directly to SH3 and powering up gave me full speed when tested from laptop - max 550/36.  I wasn't expecting this to be honest!
3. Putting Asus back in the mix (wifi off & only laptop wired in) and powering all back up in correct sequence gave me speed as I mentioned at the beginning - 275/36.
4. I'm sure I've reset Asus to factory default config along the way, with no benefits.

NB: All tests done around midnight when VM network is 'at its best' and nothing active in the house.

If I can't get the Asus to 'see' any more than 275, then I may as well downgrade my VM package again.  I can't handle SH3 in router mode as I use Asus extras I can't get on SH3 - e.g. Parental Controls - and £150+ for a new router seems unnecessary. 

Does anyone have any thoughts?

[sophist]

any QoS settings enabled on the asus?

[RedSimon]

Not when I did these tests. I saw something suggest to turn it on and also enter the down/up speeds, but no change.

[sophist · Accepted solution]

ok - and are you running any other services/features on the merlin fw (such as IDS) that might be consuming CPU etc.?  IDS can be pretty resource hungry and will definitely impact the speed of the overall connection.

I'm not familiar with the asus product set, or the merlin fw for it - but try disabling any services that you have running outside of the basic stuff and see if you see an improvement on speed.

the device a big step up from the hub, and is more than capable of passing 500mb of traffic, but not necessarily if you're doing anything complex with the traffic as it flows through the router.. 

[gary_dexter]

I found the Speedtest in the router GUI to be hit and miss. Mainly miss.

[conman33158]

Someone mentioned the other day that HW acceleration for WAN speeds over 200mbps needed enabled on their Asus router to fix their problem. Not sure if your Asus model has this but it's something else to check. Also if you have Gaming mode, turn this off as well 🙂

[RedSimon]

Thanks for your tips and guidance - I’ve cracked it!  It’s all down to Hardware Acceleration on the ASUS, which limits speed beyond about 250mb.  Once I’d done this (multiple steps below) I was hitting over 500mb on a Lan connected pc (not even direct into router) and WiFi  was better than ever too.

The fix:

Asus configuration (Merlin firmware), Tools menu, Sysinfo.  Near the bottom it showed HW acceleration as ‘Disabled (by user)’ but no other clues.  I basically turned off everything except the bare minimum...

1. Have QoS off (which it was)
2. Traffic Analyzer off (which it was.  Traffic Analyser menu, Statistics)
3. AI protection (it was on)
4. NAT acceleration to Auto (it was disabled.  LAN menu, Switch control)

Then reboot router and the HW acceleration was now showing as ‘Enabled (CTF + FA)’.   Turning these features back on may again disable HW acceleration, as would extras like Parental controls, but I’ll try and see how I get on - at least I now know what gives me top speed again.

Suck it and see I suppose, depending on your router model.  I found this article very helpful.

I may well have lost some of the features I was using, but still prefer this setup to the SH3 and speed is king with a whole family working/studying from home!

[RedSimon]

Now I got it working I have to agree... router Speedtest showing much lower than my Lan devices!

[gary_dexter]

Have a look on SMBForums for more info.

Adaptive QOS will disable one part of HW acceleration.

Traditional QOS will disable HW acceleration altogether.