AC88U Core 1 at 100% and reducing DL speed

[BB88U]

BB88U, what you need is the BRT-AC828/M.2.

http://www.snbforums.com/threads/ne...-dual-wan-vpn-router.32839/page-2#post-265829


Sure, it is above what your ISP offers now, but there is nothing in consumerland that does a true 1Gbps U/D consecutively either.

Let's see what your raw ISP speeds are (straight from the modem/ONT) and then you'll know for sure if you need to change routers.

Awesome! Now if only I hadn't spent 350EUR on this one already...

 

[L&LD]

Awesome! Now if only I hadn't spent 350EUR on this one already...

Don't feel too bad. Afaik, it isn't on sale anywhere yet.

 

[doczenith1]

I didn't see any mention of what level of NAT Acceleration was enabled during your testing. With NAT Acceleration set to auto and both FA (Flow Acceleration) and CTF (Cut Through Forwarding) enabled I get around 940 Mbps up and down with negligible cpu usage. With only CTF enabled (due to AiProtection turned on) I still get close to 940 Mbps up/down but cpu core 1 hits 100% utilization during the speed test. I've also noticed that when I run a speed test via a wifi client I see core 2 get to around 40% utilization.

Note that after making changes that affect the level of NAT Acceleration you'll need to reboot the router before the GUI will report the updated level of NAT Acceleration.

I've also found that not all speed test are created equal. And when using the ookla test not all sites are created equal so may take a little trial and error to find a site that can do 1 gig up and down.

 

[RMerlin]

OK true but it would make a LOT of sense to have networking run on two wouldn't it?

From a technical level, it's not as easy as it seems on paper. Packet routing isn't something that works really well in a multithreaded design, since ultimately, packets come in in a certain order, and must come out in that same order.

 

[BB88U]

I didn't see any mention of what level of NAT Acceleration was enabled during your testing. With NAT Acceleration set to auto and both FA (Flow Acceleration) and CTF (Cut Through Forwarding) enabled

Sorry just to confirm, this is all one setting right? I see NAT acceleration set to Auto and it says in yellow besides it: CTF (Cut Through Forwarding) is enabled.

 

[BB88U]

Sorry just to confirm, this is all one setting right? I see NAT acceleration set to Auto and it says in yellow besides it: CTF (Cut Through Forwarding) is enabled.

Wow that's crazy! I just turned off the NAT acceleration, tested and came to about the same speed. When I turned it on again, my speed was higher then it has ever been and the same as UL (ie about 115MB/s). If that did the trick, "have you tried turning it off and on again" takes on a whole new meaning for me .

However, it is not able to sustain that speed for very long, still maxing out the core 1 CPU. Something really strange is going on. Please check the image below, first peaks are DL/UL from a speed test (OOKLA), second peaks are from downloading a 10GB test file from the tele2 speed test found here: http://speedtest.tele2.net/

 

[L&LD]

If turning of NAT acceleration and then turning it on again changed the results, that indicates (to me) a need to properly and fully reset the router to factory defaults. It could be on your router, that doing it once is not enough).

If the ookla speedtest shows you hitting your ISP speeds, then the only other explanation for the varying tele2 speed test site is that your ISP is a 'home' line subscription versus a business line subscription. The difference is that a home line features 'up to speeds' (which is what ookla is showing) and a business line should guarantee some minimum speeds (which the tele2 speed test indicates you're not subscribed to). Business ISP service may be much lower advertised speeds, but in many cases are actually higher (sustained) than the 'up to' speeds that home ISP services can do.

In other words, I think your 'issue' has been solved.

Now, can you get close to those speeds (at least for the ookla tests) with WiFi?

 

[doczenith1]

I agree with L&LD that a full reset to factory defaults would be a good idea. Afterwards, with a very minimal configuration of the router, you should be able to get NAT acceleration with both FA and CTF enabled. With both enabled your cpu usage during the speed test should be very low. If not then I would think there is an issue with your router.

@L&LD The fastest I get with wifi is around 450 Mbps with my 2x2 Android phone.

 

[BB88U]

If turning of NAT acceleration and then turning it on again changed the results, that indicates (to me) a need to properly and fully reset the router to factory defaults. It could be on your router, that doing it once is not enough).

If the ookla speedtest shows you hitting your ISP speeds, then the only other explanation for the varying tele2 speed test site is that your ISP is a 'home' line subscription versus a business line subscription. The difference is that a home line features 'up to speeds' (which is what ookla is showing) and a business line should guarantee some minimum speeds (which the tele2 speed test indicates you're not subscribed to). Business ISP service may be much lower advertised speeds, but in many cases are actually higher (sustained) than the 'up to' speeds that home ISP services can do.

In other words, I think your 'issue' has been solved.

Now, can you get close to those speeds (at least for the ookla tests) with WiFi?

The line I have is fiber and should offer reliable speeds. I see speed go down when the router CPU is at 100% so I think its a matter of full blast download --> CPU overload --> recovery --> Full blast download etc. Yes wifi speed is also fine, although I hate wifi so I only use it for mobile normally. Ill try a full reset again. Cheers

 

[L&LD]

The line I have is fiber and should offer reliable speeds. I see speed go down when the router CPU is at 100% so I think its a matter of full blast download --> CPU overload --> recovery --> Full blast download etc. Yes wifi speed is also fine, although I hate wifi so I only use it for mobile normally. Ill try a full reset again. Cheers

I'm quoting myself from one of the links I gave you before:

To fully 'sanitize' a network:

• Perform a full reset to factory defaults and then minimally and manually configure the router to secure it and connect to your ISP. (As you have found out).
• After doing the above, some users have found it necessary to actually flash (again) the firmware already installed for it to work properly. Then once again manually and minimally configure the router to secure it and connect to your ISP.
• A few users have found that even with the above, clearing the NVRAM is also needed, followed once again by a minimal and manual configuration of the router.
• I have had at least a couple of customers that also needed to use the 'Format JFFS partition at next boot' option and reboot (via the gui) the router at least 3 times while waiting at least 5 minutes between reboots too to have the router full 'clean' from any previous configurations and/or JFFS partition (or file) corruption.

The above is just a partial quote (but the relevant parts). May as well do everything (now, instead of repeating everything once again, later).

 

[hexus]

Catch almost the same problem. Core1 low, Core2 - 100% instantly. TOP shows that smbd eat all this core (and my usb3.0 hdd again have a problem with ntfs table, some errors with files integrity - after 1 month of the Download Master usage).