Slow download speeds on arch compared to windows (Belkin N300 USB)

Question

I've been using the Belkin N300 F7D2101 USB wireless adapter on windows, always at a consistent 2-3 MBp/s. Ever since switching to Arch I've gotten a less consistent 350-450 KBp/s.
The adapter is using the r8712u driver, and has a rtl8192su chipset.
[mittens@mitten ~]$ lsusb
Bus 004 Device 002: ID 8087:8000 Intel Corp.
Bus 004 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 8087:8008 Intel Corp.
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 04d9:0183 Holtek Semiconductor, Inc.
Bus 001 Device 002: ID 050d:845a Belkin Components F7D2101 802.11n Surf & Share Wireless Adapter v1000 [Realtek RTL8192SU]
Bus 001 Device 004: ID 1af3:0001
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
[mittens@mitten ~]$ iwconfig wlp0s20u2
wlp0s20u2 IEEE 802.11bgn ESSID:[ssid] Nickname:"rtl_wifi"
Mode:Managed Frequency:2.412 GHz Access Point: [access point]
Bit Rate:72 Mb/s Sensitivity:0/0
Retry:off RTS thr:off Fragment thr:off
Power Management:off
Link Quality=84/100 Signal level=69/100 Noise level=0/100
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
Any ideas?
Last edited by mittens2001 (2014-10-18 07:02:10)

Answer 1

pigiron wrote:
The only suggestion I can give is to simply wait for a while.
The r8712u driver is in the "staging" portion of the kernel tree. This is where drivers that are "outside of the kernel" are first sent to get them into shape for inclusion in the main Linux source code tree.
Realtek (the maker of that wireless chip) is somewhat Linux friendly, and they typically create a Linux driver, but they have an annoying habit of using very little of the current Linux wireless/network infrastructure in that driver. They also don't assign any human resources if/when the driver is brought into the "staging" area. This forces the volunteer Linux driver developers to rewrite almost the entire Realtek driver for mainline inclusion. And they do this without signing a NDA agreement nor even being offered a free device for testing/development. So that's some tough work, and therefore takes time.
According to the current "TODO" list for the r8712u, it still needs integration to the mac80211 and lib80211 Linux wireless layers. So it still has a ways to go. Therefore what you're running now is basically the driver created by Realtek with only somewhat minor modifications.
According to here the RTL8192SU driver is going to replace the r8712u driver, would it be a better idea to just install this and see if it's usable?