Re: RTL8723BE performance regression

[Larry Finger]

On 04/03/2018 09:37 PM, JoÃo Paulo Rechi Vita wrote:
> On Tue, Apr 3, 2018 at 7:28 PM, Larry Finger <Larry.Finger@xxxxxxxxxxxx> wrote:
>
> (...)
>
> > As the antenna selection code changes affected your first bisection, do you
> > have one of those HP laptops with only one antenna and the incorrect coding
> > in the FUSE?
>
> Yes, that is why I've been passing ant_sel=1 during my tests -- this
> was needed to achieve a good performance in the past, before this
> regression. I've also opened the laptop chassis and confirmed the
> antenna cable is plugged to the connector labeled with "1" on the
> card.
>
> > If so, please make sure that you still have the same signal
> > strength for good and bad cases. I have tried to keep the driver and the
> > btcoex code in sync, but there may be some combinations of antenna
> > configuration and FUSE contents that cause the code to fail.
>
> What is the recommended way to monitor the signal strength?

The btcoex code is developed for multiple platforms by a different group than 
the Linux driver. I think they made a change that caused ant_sel to switch from 
1 to 2. At least numerous comments at github.com/lwfinger/rtlwifi_new claimed 
they needed to make that change.

Mhy recommended method is to verify the wifi device name with "iw dev". Then 
using that device

sudo iw dev <dev_name> scan | egrep "SSID|signal"

Larry