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Topic: TP-Link Archer C7: 802.11ac slower in OpenWRT than native firmware

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Alex Atkin UK wrote:

Can you give more specifics?  Is this accessing the LAN or the Internet?  What speed is your broadband supposed to be?  How does it compare to stock firmware?

This was accessing the Internet.  My broadband is 60Mbps down/10Mbps up.  I was seeing in the 20s during this test run.  It must have been an anomaly because in later runs, I am seeing comparable speeds with wifi and Ethernet now.

Compared to stock firmware, the performance is near identical.

Sorry for the false alarm.

Having a BIG problem with WIFI G speed. With the new OPENWRT 15.05 firmware WIFI G is 190KBs and my Internet over LAN Ethernet is over 60 Mbps.

Qualcomm Atheros QCA9880 802.11nac (radio0)

Channel: 36 (5.180 GHz) | Bitrate: 6 Mbit/s    

    [Signal: -73 dBm / Noise: -102 dBm]

52%     SSID: PCNET-N | Mode: Master
BSSID: C4:6E:1F:XX:XX:XX | Encryption: WPA2 PSK (CCMP)    

    Generic MAC80211 802.11bgn (radio1)

Channel: 6 (2.437 GHz) | Bitrate: ? Mbit/s

[Signal: -71 dBm / Noise: -102 dBm] NET-N    C4:36:6C:XX:XX:XX 192.168.1.100    -71 dBm    -102 dBm    585.0 Mbit/s, MCS 0, 20MHz    6.0 Mbit/s, MCS 0, 20MHz
[Signal: -59 dBm / Noise: -93 dBm]     NET-G    88:C9:D0:XX:XX:XX    ? -59 dBm    -93 dBm    6.0 Mbit/s, MCS 0, 20MHz    72.2 Mbit/s, MCS 7, 20MHz

The first setup after install didn't have second Radio.

(Last edited by mpeg3s on 18 Nov 2015, 02:10)

The 2.4 GHZ should work and had not the issues like the 5ghz (ath10k) in the Archer C7 as far as I know. Even in my crowded place I achieve 50+ Mbit/s.

Check your  /etc/config/wireless file. My settings are:

config wifi-device 'radio1'
        option type 'mac80211'
        option hwmode '11g'
        option path 'platform/qca955x_wmac'
        option channel '6'
        option txpower '20'
        option htmode 'HT40'

What is the CMD line to this up? I'm thinking of not using firmware 15.05 Wifi is really poor at setup.


hendrik.koerner wrote:

The 2.4 GHZ should work and had not the issues like the 5ghz (ath10k) in the Archer C7 as far as I know. Even in my crowded place I achieve 50+ Mbit/s.

Check your  /etc/config/wireless file. My settings are:

config wifi-device 'radio1'
        option type 'mac80211'
        option hwmode '11g'
        option path 'platform/qca955x_wmac'
        option channel '6'
        option txpower '20'
        option htmode 'HT40'

(Last edited by mpeg3s on 18 Nov 2015, 01:53)

I use vi and directly edit the configuration files. But vi is odd so anybody not familiar with it may want to use another text editor (needs to be installed via opkg though) like nano.

The other option is using uci commands where I am less familiar with. Check the wiki:
https://wiki.openwrt.org/doc/uci

and

https://wiki.openwrt.org/doc/uci/wireless

mpeg3s wrote:

Change the Channel to 6.

The new firmware 15.05 defaults for V2 is poor. I've already delete/reset the devices Radio once. Poor RADIO setup!

Check out my Ookla Speedtest result. What's your speed? http://www.speedtest.net/my-result/a/1567102251

Check out my Ookla Speedtest result. What's your speed? http://www.speedtest.net/my-result/a/1567118688

Speedtest.net is completely useless for testing WiFi performance.

I have been getting terrible results from speedtest.net lately, even wired, but my WiFi performance when copying files off my NAS is the best its ever been.

I have stopped using iperf2 or 3 as well, as they too are giving lower reading than my real-world results copying files from my NAS.

I haven't done a lot of testing on 2.4Ghz but I'm pretty sure I was getting around 30Mbit no problem.  Your best channel will depend entirely on intereference in your area.

I will try to remember testing the speed from a G dongle later.  Although its not unheard of to have some devices start to struggle once you are mixing old and new devices on the same network.

If your neighbours have WiFi its a very bad idea to use HT40.  In fact, the performance can be worse as it has to wait for every channel in the 40Mhz block to be free before your WiFi can talk.

Dude, I tested the speed with Open Signal same speed results. The new firmware has crappy WIFI! I need to revert firmware or change routers. Again, from the beginning the RADIOs were confirmed wrong with this firmware. Then I followed others instructions here in the forms to CMD reset the RADIOs and the device works but it's SLOW AS HELL discovered now!

Unless my Router is damaged (doubt it) I getting 3X speed uploading than downloading. This has nothing to do with my Cable Modem. Read below:

OLD Router Netgear 3700 OpenWRT Replaced TP C7

Speed results with the same app & devices:

Wifi G 18.38 Mbps Upload 12.07

Wifi N 39.50 Upload 11.97

I get no where near those speeds with TP-Link now. LAN is fine with the TP-Link 15.05 OpenWRT. WIFI has major problems. Note, both Radios are getting beat at least 2X by my OLD non-AC router.

Alex Atkin UK wrote:
mpeg3s wrote:

Change the Channel to 6.

The new firmware 15.05 defaults for V2 is poor. I've already delete/reset the devices Radio once. Poor RADIO setup!

Check out my Ookla Speedtest result. What's your speed? http://www.speedtest.net/my-result/a/1567102251

Check out my Ookla Speedtest result. What's your speed? http://www.speedtest.net/my-result/a/1567118688

Speedtest.net is completely useless for testing WiFi performance.

I have been getting terrible results from speedtest.net lately, even wired, but my WiFi performance when copying files off my NAS is the best its ever been.

I have stopped using iperf2 or 3 as well, as they too are giving lower reading than my real-world results copying files from my NAS.

I haven't done a lot of testing on 2.4Ghz but I'm pretty sure I was getting around 30Mbit no problem.  Your best channel will depend entirely on intereference in your area.

I will try to remember testing the speed from a G dongle later.  Although its not unheard of to have some devices start to struggle once you are mixing old and new devices on the same network.

If your neighbours have WiFi its a very bad idea to use HT40.  In fact, the performance can be worse as it has to wait for every channel in the 40Mhz block to be free before your WiFi can talk.

(Last edited by mpeg3s on 21 Nov 2015, 16:03)

Decided now not to fight the config problem with reset, delete, write CMDs and wipe the entire Router like I was installing OpenWRT for the first time.

The last OpenWRT installs were clean upgrades.

Can someone point me to the cmd process to wipe out it all from SSH/FTP?

(Last edited by mpeg3s on 21 Nov 2015, 16:11)

mpeg3s wrote:

Can someone point me to the cmd process to wipe out it all from SSH/FTP?

mtd -r erase rootfs_data
or
use failsafe mode and enter firstboot commant
or
you can upgrade with -factory image via luci (with unchecked config save option)
or
use scp to put -factory image to the /tmp, login with ssh and run sysupgrade /tmp/name_of_factory_image.bin

(Last edited by stas2z on 21 Nov 2015, 16:34)

mpeg3s wrote:

Dude, I tested the speed with Open Signal same speed results. The new firmware has crappy WIFI! I need to revert firmware or change routers. Again, from the beginning the RADIOs were confirmed wrong with this firmware. Then I followed others instructions here in the forms to CMD reset the RADIOs and the device works but it's SLOW AS HELL discovered now!

Unless my Router is damaged (doubt it) I getting 3X speed uploading than downloading. This has nothing to do with my Cable Modem. Read below:

OLD Router Netgear 3700 OpenWRT Replaced TP C7

Speed results with the same app & devices:

Wifi G 18.38 Mbps Upload 12.07

Wifi N 39.50 Upload 11.97

I get no where near those speeds with TP-Link now. LAN is fine with the TP-Link 15.05 OpenWRT. WIFI has major problems. Note, both Radios are getting beat at least 2X by my OLD non-AC router.

My point is that online speed tests are a poor way to test your WiFi.  On wired I'm only getting 30Mbit lately on all speedtest.net servers I tried but I can get 66Mbit in real-world usage.  Open Signal on the other hand has always come up short for me.

I always struggle to get my full broadband speed over WiFi, I have no idea why.  But I can get in excess of 320Mbit when accessing my LAN over 5Ghz (VHT80) and 40Mbit over 2.4Ghz (HT20).

If you want to know if WiFi is working properly, accessing a machine wired to the router is the only real way.

I also did a local copy and got speeds similar. There should not be a HUGE difference changing Routers.

As for me not choosing the best testing app please post the name of the app that meets your approval, otherwise you're not helping me here.

(Last edited by mpeg3s on 21 Nov 2015, 21:30)

I thought I was clear, there are no decent speed testing apps - at least not free ones.  The closest I got was iperf but that doesn't seem to tell the whole picture either.

The only practical test is real-world use and when dealing with mobiles/tablets even that is problematic as they often have their own bottlenecks and compatibility issues.

When you are dealing with 802.11g devices things get even more complicated.  Its generally recommended that if you are using 802.11g devices, you keep them on their own access point so they are not slowing down the network for 802.11n devices.

I'm really confused about your setup to be honest as how on earth have you gotten a 585Mbit link speed over 2.4Ghz 20Mhz channel width?  Wouldn't that require 4x4 MIMO?

My settings are:

config wifi-device 'radio1'
        option type 'mac80211'
        option channel '1'
        option path 'platform/qca955x_wmac'
        option htmode 'HT20'
        option hwmode '11g'
        option country 'GB'
        option txpower '20'

I'm don't go into real-world vs theoretical. Just know that 1 Mbs or less is much too slow for Wifi if broadband speed is not the issue. Especially, in residential homes with WIFI N 5.8 GHz.

Alex Atkin UK wrote:

I thought I was clear, there are no decent speed testing apps - at least not free ones.  The closest I got was iperf but that doesn't seem to tell the whole picture either.

The only practical test is real-world use and when dealing with mobiles/tablets even that is problematic as they often have their own bottlenecks and compatibility issues.

When you are dealing with 802.11g devices things get even more complicated.  Its generally recommended that if you are using 802.11g devices, you keep them on their own access point so they are not slowing down the network for 802.11n devices.

I'm really confused about your setup to be honest as how on earth have you gotten a 585Mbit link speed over 2.4Ghz 20Mhz channel width?  Wouldn't that require 4x4 MIMO?

My settings are:

config wifi-device 'radio1'
        option type 'mac80211'
        option channel '1'
        option path 'platform/qca955x_wmac'
        option htmode 'HT20'
        option hwmode '11g'
        option country 'GB'
        option txpower '20'

mpeg3s wrote:

I'm don't go into real-world vs theoretical. Just know that 1 Mbs or less is much too slow for Wifi if broadband speed is not the issue. Especially, in residential homes with WIFI N 5.8 GHz.

When diagnosing issues you should never dismiss any detail as irrelevant.

You are right that the link rate doesn't give a good indication of actual speed (unless its permanently stuck really low) but if its showing a figure that doesn't make sense I would be wondering why.

I know on 5Ghz the TX Rate display is wrong due to a firmware issue, but it should be accurate for 2.4Ghz.

emmeff wrote:
Alex Atkin UK wrote:

I was under the impression from the ath10k documentation that newer ath10k versions needed newer Linux kernels?
Is it actually that newer ath10k versions support newer kernels but are still compatible with older ones?

FWIW, I am now successfully running the latest firmware (firmware-5.bin_10.2.4.70.10-2) from https://github.com/kvalo/ath10k-firmwar … 88X/10.2.4 on DD, which is kernel 4.1.11.

Edit: interestingly, I am seeing about 1/3 the performance on 802.11ac vs. Ethernet with this firmware.

I have just updated to trunk with firmware-5.bin_10.2.4.70.12-2 and am really regretting it as now I'm getting half the speed I was on 15.05 with firmware-4.bin_10.2.4.48. The only reason I updated is that after the last firmware update on my Note 4, its become unstable again. sad

Interestingly, if I remove firmware-5 and put firmware-4.bin_10.2.4.48 in there instead (named firmware-4.bin), the performance is the same.
So it seems its probably not a firmware bug but something specific about OpenWRT trunk itself, perhaps some extra debugging enabled in the ath10k driver?

I did notice dmesg shows ath10k_pci 0000:01:00.0: debug 0 debugfs 1 tracing 0 dfs 1 testmode 1.
I wish I had looked for this in 15.05 as debugfs and testmode sure do not sound like the sort of things that would be enabled on a stable build and it would be nice to at least know if these are causing the performance drop.

FWIW I've also had some issues (can't quite recall what they were tho) with firmware-5.bin_10.2.4.70.12 with trunk and rolled back to firmware-5.bin_10.2.4.70.10.

I just upgraded from few months old trunk to current. Tried many settings because low 5GHz speeds, last change was to channel 40 and speed was back to normal.

config wifi-device 'radio1'
    option type 'mac80211'
    option hwmode '11a'
    option path 'pci0000:01/0000:01:00.0'
    option htmode 'VHT80'
    option txpower '14'
    option country 'FI'
    option distance '12'
    option channel '40'

config wifi-iface
    option device 'radio1'
    option network 'lan'
    option mode 'ap'
    option ssid 'WLAN5G'
    option encryption 'psk2+ccmp'
    option key 'password'

Update:

I'm using TP-Link C7 again and I did both

mtd -r erase rootfs_data

use failsafe mode and enter firstboot command

Results:

/dev/mtdblock3 is mounted as /overlay, only erasing files  (can't achieve Failsafe)

Note: when I first tried to enable the Radios N, didn't Enable. Wiped them again and set default first it yielded:

Router is better now (at least by 2X) {Radio Problem Confined}, but still not as fast as the OLD non-AC Netgear. Netgear G/N is still more consistent with Speed.

Like to "use scp to put -factory image to the /tmp, login with ssh and run sysupgrade /tmp/name_of_factory_image.bin"

have failed

scp -p openwrt-15.05-factory.bin root@192.168.1.1:/tmp/openwrt-15.05-factory.bin

Host '192.168.1.1' is not in the trusted hosts file.
(ssh-rsa fingerprint md5 67:ba:98:dc:8a:4e:16:3c:c0:ea:40:32:e4:6c:a2:23)
Do you want to continue connecting? (y/n) y
root@192.168.1.1's password:
openwrt-15.05-factory.bin: No such file or directory

I've used OpenWRT on at least two different Routers and only with this firmware did I encounter Radio problems that would not detect Radio N correct, would not enable, and is slow. Review my first setup with 15.05 https://forum.openwrt.org/viewtopic.php?id=59764

The new firmware is NOT good for auto setup!

(Last edited by mpeg3s on 22 Nov 2015, 22:36)

/etc/config/wireless file. My settings are:

config wifi-device 'radio0'
        option type 'mac80211'
        option channel '36'
        option hwmode '11a'
        option path 'pci0000:01/0000:01:00.0'
        option htmode 'VHT80'
        option txpower '17'
        option country 'US'

config wifi-iface
        option device 'radio0'
        option network 'lan'
        option mode 'ap'
        option ssid 'PCNET-N'
        option encryption 'psk2+tkip+ccmp'
        option key 'mypass'

config wifi-device 'radio1'
        option type 'mac80211'
        option hwmode '11g'
        option path 'platform/qca955x_wmac'
        option country 'US'
        option htmode 'HT40'
        option channel '1'
        option txpower '23'

config wifi-iface
        option device 'radio1'
        option network 'lan'
        option mode 'ap'
        option ssid 'PCNET-G'
        option encryption 'psk2+tkip+ccmp'
        option key 'mypass'

(Last edited by mpeg3s on 22 Nov 2015, 23:05)

PJK wrote:

I just upgraded from few months old trunk to current. Tried many settings because low 5GHz speeds, last change was to channel 40 and speed was back to normal.

config wifi-device 'radio1'
    option type 'mac80211'
    option hwmode '11a'
    option path 'pci0000:01/0000:01:00.0'
    option htmode 'VHT80'
    option txpower '14'
    option country 'FI'
    option distance '12'
    option channel '40'

config wifi-iface
    option device 'radio1'
    option network 'lan'
    option mode 'ap'
    option ssid 'WLAN5G'
    option encryption 'psk2+ccmp'
    option key 'password'

Must be a fluke then as I had just changed to channel 40 before installing trunk and it booted on 40.  I thought THAT was what caused the slow down at first.

I tried 36, 40 and 100 but the channel seems to make zero difference to throughput.

The lower the frequency the better the reception. When no difference or interference go LOW.

Alex Atkin UK wrote:
PJK wrote:

I just upgraded from few months old trunk to current. Tried many settings because low 5GHz speeds, last change was to channel 40 and speed was back to normal.

config wifi-device 'radio1'
    option type 'mac80211'
    option hwmode '11a'
    option path 'pci0000:01/0000:01:00.0'
    option htmode 'VHT80'
    option txpower '14'
    option country 'FI'
    option distance '12'
    option channel '40'

config wifi-iface
    option device 'radio1'
    option network 'lan'
    option mode 'ap'
    option ssid 'WLAN5G'
    option encryption 'psk2+ccmp'
    option key 'password'

Must be a fluke then as I had just changed to channel 40 before installing trunk and it booted on 40.  I thought THAT was what caused the slow down at first.

I tried 36, 40 and 100 but the channel seems to make zero difference to throughput.

Out of curiosity, I booted up an older laptop with a wireless g card to run some quick speedtests. However, my results were ok. So, there is no general problem with wireless g on the Archer C7 and Chaos Calmer.

My internet connection is 50mbit/s. With a wireless n device, speedtests usually show 49-50mbit/s - so there's no slowdown here. With the older laptop that only supports wireless g, the results of different speedtests vary between 19-24mbps (depending on which speedtest I use). Sure, that doesn't max out my connection but it's still much better than what mpeg3s describes.

I'm using Chaos Calmer 15.05 final. The only change is that I use firmware-4.bin_10.2.4.48 instead of the default firmware.

(Last edited by silentcreek on 25 Nov 2015, 02:00)

@mpeg3s: Re-reading my reply and the posts before, I just noticed a discrepancy here. You talk about wireless g, yet you mention channel 36 being used. That should only work with wireless n since it's a channel on the 5Ghz band which is unsupported on wireless g. So I guess you actually mean wireless n?

silentcreek wrote:

@mpeg3s: Re-reading my reply and the posts before, I just noticed a discrepancy here. You talk about wireless g, yet you mention channel 36 being used. That should only work with wireless n since it's a channel on the 5Ghz band which is unsupported on wireless g. So I guess you actually mean wireless n?

Or they mean a, as a dual-band g card would basically be an a & g card.

Its also possibly more likely there would be problems with 802.11a backwards compatibility as it was never that widely used to potentially less well tested.

Sorry, posts 151 to 150 are missing from our archive.