AC66U WAN cpu usage

I have noticed recently that when downloading my max allowed speed from ISP 100/10 (120/12 speed test) that my cpu on my ac66u is maxed out. I looked up the specs recently and found that is should be able to achieve 300 with ctf disabled and 600 with it enabled.

I have it enabled of course and no VPN client connectivity ( i do have a vpn server hosted but no clients connected)

Is anyone else noticing this issue?

What do I need to upgrade to?

In some routers the CPU maxes out when you stress test it such as the traffic is trying to utilise more bandwidth than available. This is not a bad thing if you are maxing out your internet and doesnt mean you have to upgrade.

I'm not sure about those spec's you post, they seem too high for that 3 year old platform.

Tim posted:

Disabling this acceleration knocked the simultaneous up/down routing test down to around 240 Mbps.

Click to expand...

http://www.smallnetbuilder.com/wire...1750-gigabit-router-reviewed?showall=&start=2

I would not be too concerned with the cpu usage if the router remains stable and performance is more than the ISP contract is for.

Note that the RT-AC66U is based on the same cpu platform as the RT-N66U which is an even older design. Expecting either of them today to provide high performance without breaking a sweat is asking a little too much I think?

Can you try disabling the VPN server, rebooting the router and testing again?

Do you have any other concerns about the way the router does it's job?

The only time I would be concerned about the cpu maxing out is if it didn't fluctuate at all for many, many minutes at a time. That is an indication that upgrading to a more powerful model is needed for the features and setup you use the router for.

You need to make sure that NAT acceleration is enabled if you want to offload the traffic off the CPU. Check the Tools -> Sysinfo page to determine if NAT acceleration/CTF is enabled, and if not why it isn't.

IF QOS is on this router maxes out cpu at at around 100mbit, basicly if NAT acceleration is off, it gona hit peg the cpu at max at those speeds, with NaT accleration on it will be fine though

Thanks for the feedback guys, CTF is enabled (that was the first thing i checked) and I even tried a couple of previous firmware to make sure it wasn't something new.

I could have swarn that it used to only be around 30% cpu when maxing out my WAN but i could be wrong.

I will also try turning off the VPN server to see if that makes a difference but i don't expect it to.

Also the reason why this worrys me is i don't want performance to suffer when i am maxing out my connection, when i download from newsgroups it usually maxes it out and if this is at a time when i am extending media center to wireless xbox 360's it could cause some latency.

Also if i am streaming media to mobile devices over vpn while doing these things obviously i am in need of an upgrade.

Not strapped for cash but I always like to build for worst case senarios.

I really don't need all the wireless bandwidth so i just need to find the asus with the fastest proc.

Thanks again for the feed back guys really appreciate it!

A CPU is meant to be used...

So i guess it's time for an upgrade, might as well go for the 3200 i guess, can't really see if its the same proc as the 87 or not but after 200 bucks what is another 50-60

I'm running into the same issue. my ISP just bumped me up to 300/20 and DD-WRT was capping out at 100 Mb DL, so I flashed the latest Merlin FW 378.55 and reset to factory defaults. HW acceleration is enabled and I am maxing out the CPU and only getting ~180-190 Mb DL. All wired connections here. (plugging straight into my modem gets the full 300)

@Merlin, Is NAT acceleration/CTF the same thing as hardware acceleration?

I've seen other folks claim that they achieve much more DL with this router running Merlin. I wonder what I am doing wrong?
Think I would get better results with stock ASUS FW?

TIA,

-Dave

I tried the stock firmware and it doesn't help, I am not sure what has changed but something is adding overhead to the WAN-LAN traffic.

Even on the new AC3200 i just picked up when i hit 120mbit i am still getting 50% on one core and 10% on the other core.

I could only imagine if i had 300mbit like you did i would probably still be near the top even with this new router.

Perludesi said:

I'm running into the same issue. my ISP just bumped me up to 300/20 and DD-WRT was capping out at 100 Mb DL, so I flashed the latest Merlin FW 378.55 and reset to factory defaults. HW acceleration is enabled and I am maxing out the CPU and only getting ~180-190 Mb DL. All wired connections here. (plugging straight into my modem gets the full 300)

@Merlin, Is NAT acceleration/CTF the same thing as hardware acceleration?

Click to expand...

Yes. Check the Tools -> Sysinfo page to confirm that it's really enabled. Using an incompatible feature will force it to be disabled.

Those routers with my firmware running are fully capable of hitting close to 900 Mbps with NAT acceleration enabled - numerous users are doing it. If you can't get over 100-200 Mbps, then either NAT acceleration is not enabled, or something else is wrong with your setup. For instance, as numerous posts indicate, you MUST turn off a cablemodem for 10-20 minutes when moving it between different routers (or between a router and a computer) for your connection to fully be reset at the ISP's end.