[GCC 7.2 BUILD] Optimized TP-Link Archer C7 V2 AC1750 LEDE Firmware

As far as I know FastPath is for LAN, not for WAN.
If I'm wrong, please correct me.

Hi @r00t , i want to report an issue with 464 on your build. If you are not using it its kinda spam your syslog.

ledewan6_4 (15388): cat: can't open '/tmp/464-wan6_4-anycast': No such file or directory

Beside that it produce high cpu load and usage. Meanwhile i never used 464 since i have dual stack. At the end i had to remove it from my router. Note: a reboot is needed as well because after removing the package, the spaming increase and cpu usage skyrocket into 100% with a load of nearly 6.

After that your build run nicely with in my case, had nearly tripled the performance with nat and sqm. Consider removing it from your build since it seem to be a specific problem with 464 itself.

Greetings.

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Thanks for reporting this! Some users opened bug reports about this on Github but didn't narrow it down to 464 and I wasn't able to reproduce this on my C7. I'll remove this with the next release.

2 Likes

@all
Latest nigthly is running (with keeping settings)

Thanks

21998348

As a matter of interest, would it be possible to get the modem manager included in subsequent builds or is there an alternative way in setting it up?

I have a Huawei E3372 LTE USB dongle that I would like to use as a backup.

Thank you.

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Does this work with the C7 v3? I believe it's basically the same as the v2.

Fast Path by default works on WAN but it can be enable also for LAN interface.

Hi,

After applying SQM using the same paremeters from @fRUTTiFrESH images, the bufferbloat remains on B quality (with SQM off, the quality is on B indeed).
The speedtest is working fine, 300 Mb. download and 285 MB. upload (SQM on).

My internet connection is PPPoE, do I need to change some parameter in the SQM config to get a better bufferbloat?

@Klingon

You have to repeat the speedtest a few times over a period of time. Sometimes it depends on the daytime (probably the ISP is throtheling?!)
In my case the cable ISP workload varies (so I get bufferbloat quality between A & C)

Best practice is to find suitable settings without the need to adjust or play on that settings anymore (it will just work again as expected in a few minutes/hours).

Saludos

Current Speedtest atm:

22117628

37dys_con

Danke schön for your advices @fRUTTiFrESH!!! :grinning:

I installed the latest 'stable' build and managed to lock myself out. I cant access router even with ssh.
I need help restoring to factory settings or flashing any firmware again. The problem is I can't seem to enter failsafe mode. What is the corrent procedure for this router with LEDE. Also, what ip setting do I need to set on my PC (currently static 192.168.1.2, 255.255.255.0 subnet and 192.168.1.1 getaway). Next, what port do I use putty to connect and what port to connect my LAN cable to (ethernet 1-4 or internet).
Yeah, basically I need to get into failsafe mode somehow.

Holding reset button may work for you. If that fails, you can look up TFTP procedures to recover

Tftp recovery rules! Did it in 5 mins this morning. Used the same LEDE factory bin.
Now I just need to get internet access (I was only able to connect to router last time) without locking myself out :slight_smile:

EDIT: Internet works after reconnecting wan cable from modem. Now I'm trying to set up QoS, using setup from above works fine latency wise, but cuts my download speed almost in half (set to 90% of my actual DL speed). Also, what interface to use to have one QoS rule rule them all :wink:.

From my rudimentary testing with Speedtest and my 300/30mbit Cable connection, I've found that my C7 CPU can handle it, but without SQM. My idle time goes to 0% if I run Cake though, and I get 250mbit in rather than my typical >300. I believe in this case, Cake is probably not handling most of the packets, which would result in your poor Bufferbloat results.

If I monitor the CPU and throttle down the bandwith, I have to go down to 120 (WAN-WiFi) or to 140mbit (WAN-LAN) for it to stay off 0% idle. For me, that's too much speed loss. But, I see an overall bloat improvement by applying Cake to just the egress, so setting 0/28mbit helps, and of course the C7 isn't breaking a sweat SQM'ing 30mbit.

The other thing, it seems the Fastpath conflicts with SQM, effectively disabling it. Check for a few threads on here.

If you haven't already, check out the guide on SQM setup on the LEDE site, it has a few setting tips for PPOE...

Sound about the performance i get. If i do a speedtest on my 100/40 mbit, i get like 35% cpu usage while download and using sqm. (After removing bugy 464). With my internet, i should never get over 50% with full download and upload speed at the same time. Its like about 3 times better than stable lede.

After doing some test, I agree with you @JonP

With SQM on, Archer C7 can't handle it correctly, I get strange behavior on downloads/uploads, because of the CPU. Uptime goes from load average: 0.00, 0.00, 0.04 to load average: 0.70, 0.17, 0.09 (or more) just downloading a 100 MB. file.

With SQM off, I get from load average: 0.00, 0.00, 0.04 to load average: 0.21, 0.07, 0.04 downloading a 100 MB. file.

The test were made directly to the router by SSH, to an USB PEN 2.0 plugged to the router, and testing via wget command to http://speed.hetzner.de/100MB.bin

No mobiles/computers/tablets... were plugged during the test.

I have to admit the test method maybe it's not fully reliable, but I wanted to isolate any computer/mobile..... from the test.

Thanks for your help!!!

Strangely enough, disabling PPPoE improved my performance (my line is only 25/1mbps) with QoS and reduced cpu load.
Another problem I'm having is that internet won't work after rebooting the router and is fixed only after I manually reconnect wan cable. Any thoughts on that?

Greetings

I'm also trying to use a Huawei E5573 as USB WAN connection, but so far i had no luck with it. I'm following this and this guide, but i have to install the packages with --force-depends because kernel mismatch (using either stable or nightly)

Collected errors:
 * opkg_install_cmd: Cannot install package kmod-usb-echi.
 * satisfy_dependencies_for: Cannot satisfy the following dependencies for kmod-usb-net-rndis:
 *      kernel (= 4.4.88-1-10fe3f48b906daa67e959756d0a63862) *  kernel (= 4.4.88-1-10fe3f48b906daa67e959756d0a63862) * 
 * opkg_install_cmd: Cannot install package kmod-usb-net-rndis.

various packages show that warning.
after rebooting the router these error is shown in dmesg

[   23.523998] kmodloader: 8 modules could not be probed
[   23.533102] kmodloader: dependency not loaded usbnet
[   23.545708] kmodloader: - cdc_ether - 1
[   23.552729] kmodloader: dependency not loaded usbnet
[   23.564609] kmodloader: - cdc_ncm - 1
[   23.569298] kmodloader: - g_ether - 0
[   23.576463] kmodloader: - g_mass_storage - 0
[   23.585423] kmodloader: - g_serial - 0
[   23.599042] kmodloader: dependency not loaded cdc_ncm
[   23.608462] kmodloader: dependency not loaded usbnet
[   23.617176] kmodloader: - huawei_cdc_ncm - 2
[   23.627118] kmodloader: dependency not loaded usbnet
[   23.639041] kmodloader: dependency not loaded cdc_ether
[   23.645172] kmodloader: - rndis_host - 2
[   23.653037] kmodloader: - usbnet - 0

and if I try to manually modprobe this is shown in the system log:

Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.331115] rndis_host: Unknown symbol usbnet_open (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.337332] rndis_host: Unknown symbol usbnet_skb_return (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.343712] rndis_host: Unknown symbol usbnet_tx_timeout (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.350097] rndis_host: Unknown symbol usbnet_suspend (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.356197] rndis_host: Unknown symbol usbnet_start_xmit (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.362549] rndis_host: Unknown symbol warn_slowpath_null (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.369479] rndis_host: Unknown symbol usbnet_stop (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.375307] rndis_host: Unknown symbol usbnet_generic_cdc_bind (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.382204] rndis_host: Unknown symbol usbnet_disconnect (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.388556] rndis_host: Unknown symbol usbnet_cdc_unbind (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.394909] rndis_host: Unknown symbol usbnet_probe (err 0)
Mon Sep 25 17:52:15 2017 kern.warn kernel: [  805.400822] rndis_host: Unknown symbol usbnet_resume (err 0)
Mon Sep 25 17:59:36 2017 kern.warn kernel: [ 1246.981791] usbnet: Unknown symbol warn_slowpath_null (err 0)

I have no idea where else look to make this work

I also wondered about what I was seeing in the load numbers. I was told to run top -d 1 in terminal, and watch the sirq and idle percentages. This gives you a better idea of how busy it's getting. The load average numbers in LUCI seem to be at a distance from a short term event like a 20-30sec Speedtest.

This is not an Archer C7 problem. It´s caused by the auto negotiation / auto sensing mechanism when network probing the capability of the network using low-level signalling techniques to select compatible Ethernet speeds.

I´ve tried diffrent Routers connected to the main- unit provided by the ISP [FRITZ!Box 6320 v2 Cable (um)] - almost with the same result: disable GBit/s Speed (on the ISP-Router) or use a GBit/s Switch between the devices....