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

Heres an example of the commands i use to make a firmware image

#!/bin/bash
git clone https://git.openwrt.org/openwrt/openwrt.git lede
#copies patches to lede directory, assuming you already have patches directory available.
cp -r patches /path/to/lede
cd lede
./scripts/feeds update -a
./scripts/feeds install -a
#applies patches and moves to appropriate directory
for i in patches/*.patch; do patch -p1 < $i; done 
mv ./target/linux/generic/patches-4.9/* ./target/linux/generic/pending-4.9/
rm -rf ./target/linux/generic/patches-4.9
#copies my config.seed file( i have saved) to the lede directory as .config, so when i run make menuconfig in the lede directory, it already has my previous settings.
cp /path/to/config.seed /path/to/lede/.config

Once this is complete just cd into lede and make menuconfig check your configuration settings and save, then make image. make -j1 V=s
this can be made into a shell script just copy and paste it into a .sh file.

Automatic make:

#!/bin/bash
git clone https://git.openwrt.org/openwrt/openwrt.git lede
#copies patches to lede directory, assuming you already have patches directory available.
cp -r patches /path/to/lede
cd lede
./scripts/feeds update -a
./scripts/feeds install -a
#applies patches and moves to appropriate directory
for i in patches/*.patch; do patch -p1 < $i; done 
mv ./target/linux/generic/patches-4.9/* ./target/linux/generic/pending-4.9/
rm -rf ./target/linux/generic/patches-4.9
#copies my config.seed file( i have saved) to the lede directory as .config, so when i run make menuconfig in the lede directory, it already has my previous settings.
cp /path/to/config.seed /path/to/lede/.config
make menuconfig
make -j1 V=s

HOPE THAT HELPS!

1 Like

This is ddwrt archer c7 v2 latest build:
https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2018/05-04-2018-r35874/

https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2018/05-04-2018-r35874/tplink_archer-c7-v2/


.

2 Likes

@nitromehmet
What I do:

  • download the lede source
  • crate the fixes folder inside the lede source
  • copy your patches there
  • cd lede_source and exec:
    for i in fixes/*.patch; do patch -p1 < $i; done

My opinion about forcing 40Mhz: if there are more than 30 2.4Ghz wifi networks detected the driver forces the 20Mhz channel because if you use 40Mhz under that condition not only your wifi network will work worse, you'll affect your neighbors networks.

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This have SFE?

SQM and QoS does work with fastpath and offloading...
Only if you use hw offloading (currently only on mt7621), sqm and qos does not work...

@juppin
Yep, I know, but this thread is about Archer C7 v2

1 Like

I know too... But you said that one would lose sqm/qos capability... Thats wrong

@juppin
This has been discussed a lot of times in this thread, the only option for Archer C7 v2 is fastpath, offload is only available on kernel > 4.14 which is not available for Archer C7 v2. You can enable SQM with fastpath, but you get a great performance penalty.

For mediatek based routers you can have hardware offloading, but even the main developer of this feature (nbd) says that SQM don't work with hardware offloading.

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One question, Archer C7 is MU-MIMO capable?
I mean, is a software or hardware restriction the MU-MIMO fuction is our Archer?

@Klingon
Only Archer C2600 and Archer VR2600 are MU-MIMO capable and I have not seen MU-MIMO support on the LEDE source, so I think there's no driver support yet.

1 Like

Hi there,

I built a simple version of OpenWRT with the performance patchs laying around this thread. Current snapshot, r00t's patchs (patched for 4.9), fast path, no fancy package. I fact, I don't want to use the units as WAN routers, only as part of a mesh network (I have 6 units).

But my unit is hitting a performance wall at 190mbps with nearly everything i tried. Even with a vanilla snapshot.

LAN Client 1 <wired> Archer C7 <Wifi AP> Archer C7 Client mode <wired> LAN Client 2
And even with iperf on the units, the link is still maxed at ~200mpbs.

Am I missing something here ? There is peoples who are successful to achieve far better performances with the 5ghz interface. Clearly, I have an issue with the softirqs, but I don't know what to do with this information.
Also, since I want to use them only as mesh nodes, maybe there is a lot of routing packes to remove.

Any idea ?

@Moff_Tigriss
Maybe you are stressing the CPU, check usr + sys + sirq using top. If that sum is near 100 then you are running at full utilization.

If you want to see if a CPU is struggling, it is better to simply focus on the idle %. If that's close to or hitting 0, you're running into a CPU bottleneck.

1 Like

Another day of hacking, and I have some results.

The sysconf file up here was useful. I need to do some work on it to understand why, but it's here. I'm actually not CPU limited, now. The limit is near, but i managed a constant 210mbps, with ~15% idle. I can use the web interface without hurting the bandwidth. The thing is... it's with AC@80mhz, in a perfect radio condition between two unit. I can use N@40mhz with nearly the same result.

Since the CPU is not totally maxed, it is possible that there is a bottleneck somewhere else ?

@Moff_Tigriss
Without knowing much about your configuration, I think you are reaching the router limit. Have you tried to configure your mesh network without encryption just to test?
Btw, mesh networks are complicated (form the point of view of how you can configure it), I have seen some weird configurations that "just works". If you get something that works for you with a decent speed stick with that.

Edit: I remember I saw a device called "Google Wifi", it was a 3 device mesh router that uses a recent qualcomm SoC (much better than the archer c7 v2) and under good conditions it gets like 250 - 270Mbps.

Well, i haven't any specific configuration, TBH. I removed everything tied to WAN, and the 5ghz is configured with ad-hoc on two units, with batman-adv behind. I have the same results with pure AP+Client. And all of that is without encryption.

But ! Last day, I found something interesting. The 5ghz radio is the real problem for performances, and I think that a lot of results on this thread are impacted as well.

I managed three time a sustainable 280mbps, and with a whopping 35% idle on the CPU. With multiple traffic and clients. The trick is to change a setting on the 5ghz radio (tx power do the trick, i think deactivate/activate the radio can have the same effect, but not tested yet), maybe more than one time, until you see a good iperf speed. When a radio "is right", it's good for the rest of the time (but you still need to make a new node "right" too).

Every time I tried that, it succeeded to a stabilize at 280mbps, with Ad-hoc and also with normal AP+Client. 65% cpu usage.

Now, there is some really good results in the firsts posts of this thread, using the 5ghz radio. Like 400-500mbps. So, somewhere, there is a setting or a patch who probably screwed up the ath10k stack.

Also, the "refresh" of the 5ghz radio is a phenomenon known for the Archer C7. I'm wondering if there is a way to script that.

Any plans to have a Optimized OpenWRT version under the merge ?

Still working on 4.14 with nat hardware offload. That’s the next best thing.

2 Likes

A new release is online and the nightlies have been fixed. Sorry about my absence, but I'm quite busy with other things in life and will only update this firmware every couple of months or so when it's actually needed. This is why I'm running the build script that compiles and uploads nightlies for you guys. Just use these to stay up to date even when I'm not around to respond to feature requests or apply changes to my optimizations.

Also it's pretty much impossible to dig through hundreds of replies when 80% of them are not related to this build but generic LEDE/package questions or even about other builds. Therefore if there are issues or feature requests, please submit them on Github. Cheers!

5 Likes

At all: Please take this as a reminder that this topic is intended for questions specific to @root's community build only.

For questions regarding official release / snapshot builds for Archer C7 v2, installation and configuration, please us the other available forum categories. Please use the forum search before starting a new topic.

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