Am 21.12.20 um 00:19 schrieb Rainer Suhm:
Since kernel 5.9 I do have very poor wlan performance with one of my machines.
The transmission rate is only about a tenth of normal speed (~60MB/s -> 6 MB/s).
iperf3 -c <server> shows hundreds of retries per second
--- snip ---
[ ID] Interval Transfer Bitrate Retr Cwnd
[ 5] 0.00-1.00 sec 8.55 MBytes 71.7 Mbits/sec 649 1.41 KBytes
[ 5] 1.00-2.00 sec 5.78 MBytes 48.5 Mbits/sec 366 17.0 KBytes
[ 5] 2.00-3.00 sec 5.97 MBytes 50.0 Mbits/sec 371 19.8 KBytes
[ 5] 3.00-4.00 sec 5.84 MBytes 49.0 Mbits/sec 390 17.0 KBytes
[ 5] 4.00-5.00 sec 6.21 MBytes 52.1 Mbits/sec 380 19.8 KBytes
[ 5] 5.00-6.00 sec 4.54 MBytes 38.1 Mbits/sec 299 1.41 KBytes
[ 5] 6.00-7.00 sec 6.34 MBytes 53.2 Mbits/sec 367 26.9 KBytes
[ 5] 7.00-8.00 sec 6.15 MBytes 51.6 Mbits/sec 390 19.8 KBytes
[ 5] 8.00-9.00 sec 5.65 MBytes 47.4 Mbits/sec 370 2.83 KBytes
[ 5] 9.00-10.00 sec 5.78 MBytes 48.5 Mbits/sec 377 21.2 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 60.8 MBytes 51.0 Mbits/sec 3959 sender
[ 5] 0.00-10.00 sec 60.1 MBytes 50.4 Mbits/sec receiver
--- snap ---
(this measurement was taken after booting from the current official arch iso)
The problem is only when transmitting data. Receiving (iperf3 -c <server> -R)
works ok.
No related errors/warnings in dmesg.
The problem exists since kernel v5.9 up to 10.0.2-rc1
Using other (older) WiFi firmware doesn't help.
Hardware: TUXEDO InfinityBook S 14 v5/L140CU,
with Intel(R) Wi-Fi 6 AX200 160MHz, REV=0x340
The machine runs Arch Linux, all updates installed.
On all my other laptops this problem doesn't show up.
Bisecting leads to:
--- snip ---
3d5b459ba0e3788ab471e8cb98eee89964a9c5e8 is the first bad commit
commit 3d5b459ba0e3788ab471e8cb98eee89964a9c5e8
Author: Eric Dumazet <eduma...@google.com>
Date: Wed Jun 17 20:53:26 2020 -0700
net: tso: add UDP segmentation support
Note that like TCP, we do not support additional encapsulations,
and that checksums must be offloaded to the NIC.
Signed-off-by: Eric Dumazet <eduma...@google.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
net/core/tso.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)
--- snap ---
After reverting e89964a9c5e8, everything seems ok. WLan works with expected
speed, and iperf3 doesn't show retries any more.
I confirm this for kernels 5.10.1 and 5.10.2-rc1 (00017-gc96cfd687a3f).
If I should provide more information, let me know.
Please note: I'm not on any list. So please make sure to address me explicitly
if replying to this mail.
Thx
Rainer
Sorry,
I have to resend this message, as it could not be delivered to the netdev list
because of missing TLS.
--- snip ---
Final-Recipient: rfc822; netdev@vger.kernel.org
Original-Recipient: rfc822;netdev@vger.kernel.org
Action: failed
Status: 5.7.4
Diagnostic-Code: X-Postfix; TLS is required, but was not offered by host
vger.kernel.org[23.128.96.18]
--- snap ---
For now I switched the need for TLS off.
Hope that helps.
Thx
Rainer
