[fixed] Slow wifi and strange behavior

[jasper199069]

Best Raspberry PI users,

I am having some strange issues with my raspberry pi combined with the wifi adapter.

I have a Raspberry PI model B (one of the first versions)
and I have a TP-link TL-WN-823N wifi adapter.
The PI is running the latest version of raspbian Jessie.

I have setup the adapter to connect to the wifi automatically using the wpa-supplicant information.
The network connects normally without any issues.

The issue is that at some times, when I try to connect to the pi it takes an amazing long time before it connects, if it doesn't time out.
Also when I ping the PI it takes some requests before it responds, also when it responds the respond times are very inconsistent, sometimes more than 100ms and sometimes 5ms.

I have checked/ tried to following things:
I have added mac_usb_current=1 only to find out that was for B+ and newer :S
I have checked to power managerment this is currently off.
I have checked other wireless devices, these have latency of 1 - 3ms per ping.
Also I have checked the wired connection, and this ping is also 1 - 3ms per ping.

Do you have any idea's of things I can try? Or perhaps a fix for this issue?

Kind Regards and Thanks in Advance,

Jasper van Rijbroek

[epoch1970]

Power management perhaps?
You could do "modinfo <module_name>" and see if a module option that you can activate/deactivate in the wifi driver...

[jasper199069]

Power management perhaps?
You could do "modinfo <module_name>" and see if a module option that you can activate/deactivate in the wifi driver...

I have checked the power management in iwconfig and that one was set to off,
I have also done some more changes and will review them in the upcoming time,
also the kernel has been updated to the newest (stable) version.

As part of the slow ping I have changed the wifi channel and that already improved a lot!

[jasper199069]

Changes are reviewed and it now seems to run perfect.

For the other people who have issues with an external wifi adapter, this has fixed it in my case:

Create the file /etc/modprobe/8192cu.conf with the following content:
# Disable power management
options 8192cu rtw_power_mgnt=0 rtw_enusbss=0

And run the following commands: rpi-update and apt-get update && apt-get upgrade

Thanks everyone!