Internet speed slow on Ubuntu 18.04.1 with TP-LINK TL-WN821N

Question

On Windows 10 I get ~90Mbps download and upload, while on Ubuntu 16.04 I get ~9Mbps download and ~1Mbps upload.

Why is there such a big difference and what do I do to speed it up? The two OS are set up on the same hardware with dualboot.

I am using a wireless network adapter TP-LINK TL-WN821N made by belkin and since it is working fine on Windows I suspect its some driver issue or something.

--- Output of lsusb ---

Bus 002 Device 004: ID 046d:c31c Logitech, Inc. Keyboard K120
Bus 002 Device 003: ID 046d:c077 Logitech, Inc. M105 Optical Mouse
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 005: ID 2357:0107  
Bus 001 Device 003: ID 03f0:e207 Hewlett-Packard 
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

--- Output of lsmod | grep rtl ---

rtl8xxxu              122880  0
mac80211              778240  1 rtl8xxxu

--- Content of /etc/modprobe.d/ ---

alsa-base.conf
amd64-microcode-blacklist.conf
blacklist-ath_pci.conf
blacklist.conf
blacklist-firewire.conf
blacklist-framebuffer.conf
blacklist-modem.conf
blacklist-oss.conf
blacklist-rare-network.conf
blacklist-watchdog.conf
dkms.conf
fbdev-blacklist.conf
intel-microcode-blacklist.conf
iwlwifi.conf
mlx4.conf
nvidia-384_hybrid.conf
nvidia-graphics-drivers.conf

--- Content of /etc/modprobe.d/iwlwifi.conf ---

# /etc/modprobe.d/iwlwifi.conf
# iwlwifi will dyamically load either iwldvm or iwlmvm depending on the
# microcode file installed on the system.  When removing iwlwifi, first
# remove the iwl?vm module and then iwlwifi.
options iwlwifi 11n_disable=1 led_mode=1 swcrypto=1

remove iwlwifi \
(/sbin/lsmod | grep -o -e ^iwlmvm -e ^iwldvm -e ^iwlwifi | xargs /sbin/rmmod) \
&& /sbin/modprobe -r mac80211

EDIT: MTU of the adapter:

wlx503eaa683858
MTU:1500

EDIT 1:

 1?: [LOCALHOST]                                         pmtu 1500
 1:  192.168.0.1                                          13.435ms reached
 1:  192.168.0.1                                          13.473ms reached
     Resume: pmtu 1500 hops 1 back 1

EDIT 2: I upgraded from 16.04 to 18.04.1 today, but the issue is still present. My WiFi adapter is listed as disconnected in nmcli after restart and I have to remove/add it again to the USB so it can properly work.

Answer 1

我有和你完全相同的问题，我通过这样做解决了它：

1. rtl8192eu从这里安装驱动程序：

https://github.com/clnhub/rtl8192eu-linux（我用的是这个）

或在这里：

https://github.com/Mange/rtl8192eu-linux-driver

2. 加入blacklist rtl8xxxu​/etc/modprobe.d/blacklist.conf
3. 重启。

Answer 2

我有 TP-Link TL-WN821N v4，并且具有完全相同的慢速 DL 速度（UL 通过 speednet 进行了良好测试），所以我在这里发现了这一点，他们建议禁用其中一个 rtl 驱动程序，结果就成功了。

Linux下网速很慢，但Windows下不慢